[HN Gopher] US Department of Energy: Fusion Ignition Achieved
       ___________________________________________________________________
        
       US Department of Energy: Fusion Ignition Achieved
        
       Author : novateg
       Score  : 2725 points
       Date   : 2022-12-13 16:44 UTC (1 days ago)
        
 (HTM) web link (www.energy.gov)
 (TXT) w3m dump (www.energy.gov)
        
       | already wrote:
       | It's a big deal, it will change the way people live. Hopefully it
       | also help to eliminate wars, the war for the natural resources
       | and land.
        
         | amelius wrote:
         | There will probably still be wars over other natural resources.
        
         | standardUser wrote:
         | Currently, there are a couple dozen authoritarian regimes, most
         | heavily armed, that are almost entirely funded by fossil fuel
         | exports. That makes me fear things will get worse before they
         | get better.
        
           | Arubis wrote:
           | True; however, this was already the direction things were
           | headed for said regimes as much of the world has begun to
           | focus on energy security. On the upside, perhaps the lowered
           | long-term demand for fossil fuels will reduce the risk of
           | additional resource discoveries leading to more despotic
           | regimes.
        
         | bushbaba wrote:
         | Maybe. Fusion energy might be more expensive than current forms
         | or has undesirable yet to be known side effects.
         | 
         | People said the same of nuclear and here we are.
        
           | eastbound wrote:
           | The negative effect of nuclear were known in 1927 (Hermann
           | Joseph Meller). It would be surprising if we discovered
           | another form of radiation, given calculations lead us far
           | further without showing new forms of radiations.
        
           | seandoe wrote:
           | And had we continued to develop and improve upon fission we'd
           | probably be in a better place.
        
           | dal wrote:
           | You mean like tearing a hole in the fabric of space and time
           | and opening a hell portal to another dimension?
        
             | jrootabega wrote:
             | That only happened ONCE.
        
           | sh1mmer wrote:
           | People also said the same thing about wind and solar, and
           | those still have some downsides but they are also rapidly
           | becoming the cheapest current form of peak energy, or with
           | cheaper grid storage, energy period.
           | 
           | Sci-if authors have been talking about both solar and fusion
           | for years, and now solar has been industrialized why wouldn't
           | we be excited to see progression in fusion?
        
       | puttycat wrote:
       | 2022, not ordered by importance: Dall.E 2, Chat-GPT, Fusion
       | Ignition. Can't wait for 2023.
        
         | freediver wrote:
         | Putting these in the same basket is hardly justified.
        
           | alasdair_ wrote:
           | True. AI will have a much bigger impact on humanity in the
           | next two decades than fusion will.
        
           | hoten wrote:
           | Can you elaborate? Someone with no context can read your
           | comment either way.
        
           | zhrvoj wrote:
           | No, first two will use third. Nikola Tesla dreamed of free
           | energy for the world. I don't think they dream the same... So
           | entropy will go down now?
        
           | low_tech_punk wrote:
           | AI can be quite useful in real-time computation for magnetic
           | confinement. But sure, that's beyond GPT-3's current
           | capability.
        
             | low_tech_punk wrote:
             | And at some time point in the future, the fusion generated
             | energy will be used for training the power-hungry AI to
             | improve the efficiency of fusion.
        
       | megaman821 wrote:
       | If ignition was achieved, why would they have to keep on shooting
       | more fuel pellets? Shouldn't they just ignite one fuel pellet and
       | feed in more fuel?
        
         | jeffbee wrote:
         | That's not really how NIF works. It's really a tiny bomb. It
         | destroys the apparatus every time. It even wrecks the optics in
         | the laser primary, which they have to regularly replace.
        
       | mansoor_ wrote:
       | A couple points:
       | 
       | - Yes the efficiency of the laser is poor and modern tech is more
       | efficient, but not enough to make it an energy producing process.
       | The best lasers are ~50% energy efficient.
       | 
       | - This can only be maintained for short periods of time and the
       | time to restart the process in long. Not only that, tritium is a
       | rare isotope. These are probably the largest challenges to
       | overcome.
       | 
       | - The energy is released in the form of high-speed particles, and
       | there is no efficient energy capture process.
       | 
       | The significance of their achievements is overblown. Yes, they
       | achieved ignition, but no it is just an incremental process
       | towards commercial fusion power.
        
       | frellus wrote:
       | I hate to ask this, but have to ... is there any danger of these
       | discoveries being weaponized easily by hostile countries? i.e.
       | does this make unconventional weapons more accessible to
       | countries who otherwise have embargoes on technology and material
       | to make atomic weapons?
        
         | frellus wrote:
         | Oops, answered my own question I guess:
         | 
         | https://en.wikipedia.org/wiki/Pure_fusion_weapon
         | 
         | That ain't good. Although fusion is clearly the future of
         | energy, we have to get our sh*t together on earth so we don't
         | kill ourselves off or devolve with endless wars. Or give up and
         | use fusion to leave the planet efficiently.
        
           | mbauman wrote:
           | > That ain't good.
           | 
           | Your takeaway does not match that article. The article
           | details how "no measurable success was ever achieved" and
           | that the large amount of energy required to start fusion is
           | hugely prohibitive.
           | 
           | I don't see how the NIF's success here changes that.
        
           | jameshart wrote:
           | From your wiki source:
           | 
           | > The power densities needed to ignite a fusion reaction
           | still seem attainable only with the aid of a fission
           | explosion, or with large apparatus such as powerful lasers
           | like those at the National Ignition Facility, the Sandia
           | Z-pinch machine, or various magnetic tokamaks. Regardless of
           | any claimed advantages of pure fusion weapons, building those
           | weapons does not appear to be feasible using currently
           | available technologies
           | 
           | Nothing about this result from NIF seems to suggest that
           | igniting fusion is any easier than previously suspected.
        
           | rubyist5eva wrote:
           | I don't see how this is any different to mutually assured
           | destruction via nuclear weapons.
        
           | tinco wrote:
           | So.. we attack our enemies by building large fusion power
           | plants in their countries, and then blowing them up? Why not
           | just build a traditional nuclear fission power plant and blow
           | that up? It seems that would be a lot cheaper.
        
           | kimbernator wrote:
           | We already have tens of thousands of nuclear weapons spread
           | across the planet, with only two ever actually being aimed at
           | anyone. Lots of problems but the threat of weapons at this
           | scale are a well-feared thing already.
        
         | JumpCrisscross wrote:
         | > _is there any danger of these discoveries being weaponized_
         | 
         | Any advance in energy production or propulsion has a weapons
         | counterpart.
        
         | mnd999 wrote:
         | Fusion bombs (H bombs) have existed for a long time.
        
           | chasd00 wrote:
           | > Fusion bombs (H bombs) have existed for a long time.
           | 
           | and their yield can be made arbitrarily large with designs
           | perfected in the 50s. I don't see this tech contributing to
           | weapons. ...well maybe the lasers i guess but not the fusion
           | at least.
        
         | saul_goodman wrote:
         | You have to remember that all of the classified details about
         | US hydrogen bomb designs we have were leaked from leaked from
         | Russia after the Soviet Union broke apart. And yet only two
         | countries have managed to become nuclear states since then
         | (Pakistan and North Korea).
         | 
         | It's the engineering that makes nuclear weapons hard to do, not
         | the knowledge.
        
         | jameshart wrote:
         | A process which has been finally accomplished at one of the
         | most advanced research facilities in the world after decades of
         | effort, and which requires as an energy input almost as much
         | energy as the process produces, is not _easily weaponized_ ,
         | no.
         | 
         | Fusion reactions are hard to start. To use one as a weapon
         | would require you to deliver the fusion fuel together with a
         | source of enough energy to start the fusion reaction off. So
         | the most effective way to do so has historically been to
         | trigger them with a nuclear fission reaction from an atomic
         | bomb - which results in a Hydrogen bomb.
         | 
         | In other words, weaponizing fusion generally requires you to
         | already have an extremely powerful weapon.
         | 
         | Weaponizing this laser based inertial confinement fusion
         | approach requires you to deliver a facility the size of the
         | Lawrence Livermore lab plus the electricity generating capacity
         | of a significant part of the west coast of America onto your
         | target.
        
         | tinco wrote:
         | There are much simpler ways to generate fissile material for
         | dirty bombs. This technology doesn't seem to be weaponisable in
         | any other way that I can tell.
        
         | Steuard wrote:
         | I'm not an expert (I'm a physics prof who once took a seminar
         | on nuclear arms control back in college), but what they're
         | trying to do here is much, much harder than making an atomic
         | bomb. If you want nuclear weapons, this work on carefully
         | controlled and contained fusion is close to the opposite of
         | what you'd need to do. (Fusion power is in general much cleaner
         | than fission, at least where lasting radioactivity and waste
         | are concerned.)
        
         | alfor wrote:
         | Fusion bombs (H-bombs) were functional in 1952
        
         | anfilt wrote:
         | Like a fusion reactor can be used as a neutron source to
         | effectively make a breeder reactor.
         | 
         | However, most countries can dig up rocks out of the ground with
         | radioactive isotopes that can act as a neutron source. However,
         | this has legitimate uses as well from research to medical
         | imagining. Also any power generating reactor is gonna want to
         | use those neutrons to make Tritium otherwise it would quickly
         | run out fuel so not something you just want use on something
         | unrelated to running the fusion reactor.
        
         | scarier wrote:
         | The short answer is no.
        
         | Quarrelsome wrote:
         | from my layman understanding I believe fusion reactions are
         | unlike fission reactions in that if they escape the confines of
         | their environment they fizzle out as opposed to runaway like a
         | nuclear explosion.
        
       | dang wrote:
       | Related ongoing thread:
       | 
       |  _Nuclear-fusion lab achieves 'ignition': what does it mean?_ -
       | https://news.ycombinator.com/item?id=33971953 - Dec 2022 (82
       | comments)
       | 
       | Two threads from before the announcement:
       | 
       |  _Fusion energy breakthrough by Livermore Lab_ -
       | https://news.ycombinator.com/item?id=33945863 - Dec 2022 (755
       | comments)
       | 
       |  _Secretary Granholm to announce major scientific breakthrough by
       | DOE [video]_ - https://news.ycombinator.com/item?id=33968357 -
       | Dec 2022 (160 comments)
        
       | citilife wrote:
       | Given the resulting output was "2x higher than expected", I'll
       | wait patiently for any peer reviewed work on the subject and a
       | replication (or improvement) of the results.
       | 
       | In the presentation they mentioned they couldn't reproduce the
       | results immediately due to the containment imperfections -- at
       | least that was my understanding.
        
       | phtrivier wrote:
       | Since I absolutely decided to take this in the worst possible way
       | (get the downvotes ready)
       | 
       | What is the timeframe for those lasers to light a bulb somewhere,
       | vs the timeframe of those lasers killing someone on a battlefield
       | ? (As in, how much of is applicable for the military?)
        
         | adventured wrote:
         | I'm not sure what you're talking about. What is it you think
         | you took in the worst possible way?
         | 
         | The lasers in question are mediocre for battlefield use. The
         | consequences for the military are trivial, unless you're
         | talking about 70 years from now when the US military is using
         | fusion to power some of its military bases, subs or carriers.
        
           | phtrivier wrote:
           | I decided to take this "fusion breakthrough" with a massive
           | dose of salt additionned with twice it's weight in pepper and
           | bile.
           | 
           | At least the Nature article had a good ratio of actual
           | information about the experiment, its limitations and
           | prospect, as opposed to massive hyperbole from other
           | commenters already popping the champagne as if the energy
           | crisis was over.
           | 
           | This made sound grumpy, which, truth be written, I am.
           | 
           | (And, jealous, too, of course. I wouldn't mind a bit of
           | actual success, once in a while.)
           | 
           | Or maybe the grunts working on the experiment know better,
           | and are _also_ grinding their teeths at the PR effort ? Maybe
           | _they_ also feel unsatisfied because they still haven't met
           | their own goal ? I suppose nuclear fusion physicists must
           | have imposter syndrome, too ? Who knows.
        
         | [deleted]
        
       | leephillips wrote:
       | Old news: https://www.nature.com/articles/nature13008
        
       | johnthuss wrote:
       | "NIF, the world's largest and most energetic laser
       | system...-located at LLNL in Livermore, Calif.--is the size of a
       | sports stadium"
       | 
       | That's an important piece of information - the thing is gigantic!
        
         | valine wrote:
         | Even if it doesn't get smaller (unlikely), we as a society
         | build stadiums all the time. Large construction projects are a
         | small price to pay for abundant clean energy.
        
         | [deleted]
        
         | 93po wrote:
         | Why is it important? I picked a random nuclear plant in the US
         | (Palo Verde Generating Station) and it's 4000 acres/more than 6
         | square miles.
        
       | aidenn0 wrote:
       | So for my entire lifetime Fusion has been 30-50 years away. Now
       | it's 29-49 years away?
        
         | jackspratts wrote:
         | correct. about as long as a typical academic research career,
         | with an extra margin thrown in for emeritus positions to be on
         | the safe side. get the boffins' grand kids through college etc.
         | anyway, there won't be grids in 50 years. or if for some
         | sentimental reason there still are 95% of us will be off the
         | failure prone things while making, storing and using our own
         | uninterruptible power safely at home. much sooner really. i
         | can't even imagine being on the grid in 10 years let alone 49.
         | no way then to distribute the staggering costs for what will be
         | the planet's most expensive and complex power plants.
         | 
         | - js.
        
       | over_bridge wrote:
       | Are there any thoughts on how this will become a power plant yet?
       | It's awesome to see it filled up, reacted and then reset as a
       | proof of concept, but can it ever be a continuous flow through
       | the chamber without losing that ignition temp? Or will it be more
       | like a 4 cylinder engine where each reactor is at a different
       | stage of being filled, heated, reacting and emptying, with the
       | net result being continuous?
       | 
       | Edit: Taking the internal combustion metaphor further, I'm
       | imagining these connected in a circle. The grid is the starter
       | motor to power the first laser, then each active chamber powers
       | the laser on the next one (probably by capacitor not directly).
       | Thus the energy production moves around the circle with each
       | chamber being flushed and refilled before the laser powers back
       | on. How far off is that image in my head? I've never actually
       | seen it described
        
         | gateroid wrote:
         | NIF never was designed to be a power plant or have anything to
         | do with power generation. This is something most commenters
         | don't appear to appreciate. It's an experimental facility that,
         | when distilled to its simplest explanation, lets us study
         | things when you squish them really, really hard. It turns out,
         | fusion is one of the things you can study when you squish stuff
         | really hard - and one of the big challenges was controlling how
         | you do the squishing (which turns out to be pretty difficult).
         | 
         | There are lots of other problems that NIF also studies that
         | boil down to "what does this do when we squish it" that have
         | nothing to do with fusion or energy production. Aside from the
         | weapons program applications, there are experiments that take
         | place there in materials science, understanding extreme
         | environments ("what do these elements we believe sit in the
         | core of Jupiter act like at those pressures?"), etc.
         | 
         | TLDR: Think of NIF as a lab for energetically squishing things.
         | It's not a power plant, it's not a prototype for a power plant,
         | it's not a pre-prototype for a power plant, etc. It's a lab for
         | basic physics research. It's about as close to being a
         | prototype for a power plant as a test tube in a lab full of
         | hydrocarbons is to being a prototype of an internal combustion
         | engine.
        
           | over_bridge wrote:
           | Yeah obviously. I was asking about the next stage.
        
       | brofallon wrote:
       | I'm still a little unclear on the benefits that fusion offers
       | compared to things like wind and solar. I understand that we need
       | to develop better storage technologies for the energy produced by
       | wind and solar, but that seems so much easier than the challenges
       | currently facing fusion. Wind and solar just seem so far ahead of
       | fusion already - they're pretty cheap and very widely deployed on
       | a global scale. In comparison fusion seems very expensive and
       | unproven and even when we get everything to work it might not be
       | much better than a solar farm with a big battery pack. But maybe
       | I'm missing something important about the economics?
        
         | anon291 wrote:
         | Solar and wind have massive environmental impacts. Fusion's
         | foot print is much smaller for the same output. Batteries are
         | rather dangerous. Fusion is -- as far as I understand it --
         | much less likely to escape a reactor due to how difficult it is
         | to sustain the reaction. Moreover, it's more dependable.
         | 
         | So in sum, the advantages are (1) dependability, (2) safety,
         | and (3) small footprint.
        
           | josho wrote:
           | > Solar and wind have massive environmental impacts
           | 
           | Got a source for this? The only time I've seen this has been
           | political talking points that had no backing.
        
             | anon291 wrote:
             | My source is the fact that solar panels cause shade on the
             | ground and squander energy that would normally be going
             | towards developing biomass into developing energy instead.
             | It just doesn't seem healthy for the animals and
             | environment that live there. Especially with the talk of in
             | ground installation, which basically destroys entire
             | environments and soils and covers it with impermeable
             | membranes. That's not great for soil health.
        
               | grecy wrote:
               | I've driven many many tens of thousands of miles through
               | landscapes with intense sun and extremely close to zero
               | vegetation or life.
               | 
               | Damaging that has got to be a lot better for the planet
               | than coal or nuclear.
        
               | anon291 wrote:
               | Even the great deserts of the southwest have life. In
               | fact, I challenge you to drive through these tens of
               | thousands of miles of landscapes in the hour or two after
               | a rainstorm and tell me they're dead. You're missing out
               | if you've not seen the desert in bloom.
               | 
               | I grew up by the desert, and I don't know why people
               | think it's dead. There are some extremely fragile
               | ecosystems there.
        
               | grecy wrote:
               | > _great deserts of the southwest_
               | 
               | Sounds like you're talking about a single country?
               | 
               | I'm talking about when I've driven through the Sahara
               | (West and East side), Namib, Simpson, Great Sandy,
               | Gibson, etc. etc.
               | 
               | There is a HUGE amount of land on earth for things like
               | solar and wind.
        
         | xzlzx wrote:
         | Consistent baseline grid load is the difference.
        
         | karaterobot wrote:
         | Apart from the safety improvements and environmental benefits,
         | it's a way to produce a ton of energy. I believe it's about 4
         | times as much energy from fusion compared to fission with the
         | same amount of fuel. I'm a fan of solar and wind, but it's
         | going to be way easier to power the entire world sustainably if
         | you've got fusion in the mix.
        
         | ridgeguy wrote:
         | I think when comparing PV/wind to nuclear (fusion or fission)
         | generation, we should include the cost of storage for
         | renewables in the comparison.
         | 
         | Renewable generation + storage gives a system that's capable of
         | meeting base load needs, just as nuclear generation does. Cost
         | comparisons among base load-capable technologies is a better
         | way to evaluate the economics, IMHO.
        
         | abecedarius wrote:
         | High power density. Start and stop on demand. Abundant fuel is
         | another advantage, but in our neighborhood sunlight is also
         | abundant. Fission also has good power density, but not so good
         | on the start/stop flexibility.
        
         | bitcurious wrote:
         | Wind and solar have a max theoretical output that is
         | constrained by physical space and competition for its use, in
         | addition to weather patterns, etc.
         | 
         | Fusion energy has a theoretical max that's orders of magnitude
         | higher.
         | 
         | Wind+solar is the path to decarbonization and sustaining our
         | current world.
         | 
         | Fusion is the path to post scarcity. If/when we get scalable
         | commercial fusion, it'll be like the transition to oil -
         | society will radically change, in ways we can't predict.
        
           | vlovich123 wrote:
           | > Fusion is the path to post scarcity. If/when we get
           | scalable commercial fusion, it'll be like the transition to
           | oil - society will radically change, in ways we can't
           | predict.
           | 
           | Except this is also true for fission. So if fission has
           | failed to transform society, why do you think fusion will?
        
             | pertymcpert wrote:
             | Uh because building fission reactors, despite being fairly
             | safe, is still a risk compared to fusion? We don't want to
             | put fission reactors in every town, but we could one day
             | with commercial fusion. And the sheer amount of energy we
             | could harness would allow us to do insane things.
        
               | vlovich123 wrote:
               | > despite being fairly safe, is still a risk compared to
               | fusion
               | 
               | I recommend you read up on the Gen IV reactor designs.
               | They're totally safe - meltdowns are impossible because
               | of the way the reactor is built. If anything catastrophic
               | happens, the reaction stops and can never get to a
               | runaway reaction (physically impossible). Look up Gen 4
               | reactors. Those will be available before fusion even gets
               | off the ground (and I'll note that fusion has 0 reactors
               | built so who knows what kind of safety issues actually
               | come up when engineering theory hits the road).
               | 
               | Even Gen III reactors are fine to put up everywhere (20x
               | margin over Gen II) and Gen III+ reactors continue with
               | the theme of adding passive safety measures that would
               | prevent accidents like Fukushima and Chernobyl. Critics
               | who rate any possibility of accident as unacceptable will
               | never be pleased but that's not a reasonable position to
               | take because nuclear energy isn't built in a vacuum and
               | global warming and existing coal power poses a
               | significantly higher threat and renewables and batteries
               | simply can't scale no matter how hard we believe.
               | 
               | Fukushima and Chernobyl were Gen II designs which do have
               | a cost advantage and EVEN WITH THOSE ACCIDENTS those
               | designs are safer than existing coal and LNG power plants
               | we are fine with having all over the place (nuclear is
               | slightly safer than wind). Even Gen II designs built
               | today are a fair bit safer than Chernobyl and Fukushima.
               | Fukushima also ignored many and repeated safety warnings
               | from internal and external reports although critics will
               | generally point to this as a general criticism against
               | all reactors (even though Fukushima still failed
               | comparatively harmlessly all things considered).
               | 
               | Even with all of that, the death rate per kWH generated
               | is drastically safer than coal and on par with wind and
               | solar. Also construction costs tend to go down when the
               | regulatory environment doesn't inhibit building reactors
               | due to political fears that aren't grounded in the actual
               | engineering.
               | 
               | I'll also note that China is building many many nuclear
               | reactors and Russia is also following suit. So from a
               | competition/national security perspective, China and
               | Russia both have access to significantly more clean
               | energy and more energy independence than we do.
               | 
               | Look. I understand there are problems with fission
               | reactors. They remain the only feasible way to generate
               | nuclear power in the next 60-100 years at scale. Yes
               | there are downsides and risks. However there's one big
               | upside vs fusion: it exists. It's possible to build these
               | plants now without physics and engineering breakthroughs
               | we haven't made yet. The advantages of fusion are safety,
               | nuclear waste management, theoretical proliferation
               | concerns. There's no reason to believe construction costs
               | will be significantly lower. Even if they are, we're not
               | even close to the first real commercial power plant even
               | with this achievement as impressive as it is from a
               | progress perspective.
        
         | thehappypm wrote:
         | It's potentially just a much better version of fission.
         | 
         | Fusion won't cause a runaway reaction -- in fact it's brutally
         | difficult to get it to react at all, hence why this is an
         | achievement.
         | 
         | It also doesn't use materials that can be used for a bomb,
         | again unlike fission.
         | 
         | As a result it has the potential to be cheaper to implement,
         | cheaper to fuel, with no meltdown risk.
        
           | dharmab wrote:
           | Isn't tritium used in fusion and a potential weapons
           | material?
        
             | devmor wrote:
             | It's a fission yield booster. It's as much of a weapons
             | material as charcoal is.
        
             | mlyle wrote:
             | It's not controlled. It does help boost some fission
             | weapons. But it's not the hard part or critical piece of
             | producing a nuclear weapon, and you can get by without it.
             | 
             | To illustrate how little it's controlled-- I have a little
             | bit on my keychain as an alpha source with a phosphor so my
             | keyring always glows.
        
           | dogma1138 wrote:
           | Depending on the scale and reactor design, we have really
           | good examples of run away fusion reactions. Run away
           | reactions are easy, controlled ones are hard.
           | 
           | And whilst I won't doubt that if fusion ever becomes
           | commercially viable the reactors would be walk away safe it
           | doesn't mean that you don't need to account for that in your
           | design.
        
             | [deleted]
        
             | willis936 wrote:
             | What is an example of a run away fusion reaction?
        
               | dogma1138 wrote:
               | The US strategic arsenal.
        
               | blamestross wrote:
               | A Hydrogen Bomb. It is basically using a nuke (fission)
               | to trigger fusion instead of lasers.
        
               | willis936 wrote:
               | That is a run away fission reaction that ignites a short
               | lived fusion reaction. We don't even talk about neutron
               | populations or k factors in fusion because there is no
               | avalanche effect possible.
        
           | valine wrote:
           | Also don't forget the biggest benefit over solar/wind: it
           | keeps on generating power on cold windless nights.
        
             | jszymborski wrote:
             | No need to worry about Cold Dunkelflaut!
             | 
             | https://www.youtube.com/watch?v=Q8xsg9iK5yo
        
         | zardo wrote:
         | > But maybe I'm missing something important about the
         | economics?
         | 
         | I think you've understood it.
         | 
         | Imo fusion is never going to be able to compete with
         | renewables+storage with the energy being captured from
         | neutrons. Maybe reactions that release energy in charged
         | particles or photons could, but they're even harder to do.
        
           | Analog24 wrote:
           | Could you elaborate on your point a bit more? If you're
           | talking about utilizing the weak force vs. the residual
           | strong force then I'm not sure this argument holds up.
           | 
           | Also, when comparing to renewable+storage you have to
           | consider how much land has to be dedicated to energy use in
           | these scenarios. Wind and solar require orders of magnitude
           | more than a potential fusion reactor (or an existing fission
           | reactor).
        
             | zardo wrote:
             | Just referring to what particles the released energy is
             | carried in.
             | 
             | The easiest fusion reactions to make happen release most
             | energy as neutrons. But neutrons are, from a practical
             | standpoint, a huge pain in the ass to deal with. They just
             | fly off until they hit another atomic nucleus.
             | 
             | They irradiate the structure of reactor, making it
             | radioactive and weakening it, neccesating periodic
             | replacement. This means handling radioactive materials,
             | which as the existing nuclear power industry demonstrates,
             | is hard to make cheap.
             | 
             | Reactions that release excess energy as charged particles,
             | though all harder to actually do, leave you with charged
             | particles that can be directed by electric or magnetic
             | fields and can be used for direct enerergy conversion.
             | 
             | Yes solar requires a lot of surface area, but fusion power
             | is just not looking like it will be anywhere near cheap
             | enough for the real estate savings to matter.
        
               | Analog24 wrote:
               | Neutrons aren't that hard to capture. They are certainly
               | harder to capture than charged particles but there are
               | plenty of materials that are dense enough to reliably
               | capture neutrons. This is how heat is extracted from the
               | reaction to use in a generator. The activation of the
               | containment material is a problem but it's not even close
               | to the level it is for fission reactors where you're
               | forced to deal with spent fuel rods.
               | 
               | At the moment fusion is obviously not cheap but no one is
               | planning on using the technology in its current form for
               | actual power generation. The processes involved will all
               | get more efficient and given the astronomical upper
               | limits of energy output from fusion it doesn't take a big
               | stretch of the imagination to think that it will
               | eventually be preferable to solar and wind power. There's
               | no guarantee that will happen but hopefully this
               | breakthrough will trigger more investment and momentum to
               | make it a reality. I also want to add that I'm very pro
               | solar and wind, especially in the short term.
        
         | UltraViolence wrote:
         | Much more compact, less use of land or sea real estate, more
         | power produced per volume and throttleable.
        
         | jasonhansel wrote:
         | If we get an order of magnitude more energy, we can do an order
         | of magnitude more things; fossil fuels gave us the Industrial
         | Revolution, and nuclear fusion may unlock something similar.
        
         | dark-star wrote:
         | Wind and solar only provide power during wind / during the day.
         | Fusion can provide 24/7 power. Battery packs can only store so
         | much energy, and Lithium is a contested resource as most of the
         | Lithium produced is required by the automotive industry these
         | days, and the largest deposits are in regions where you maybe
         | don't want to get your Lithium from (child labor, unsafe
         | conditions, politically unstable countries, etc.)
         | 
         | But yeah, future energy will be a mix of available
         | technologies, not a single technology alone. So you need e.g.
         | fusion (or fission) for "baseline" power and wind/solar for
         | peaks
        
         | ragebol wrote:
         | Fusion brings the power of the stars directly to us, without it
         | capturing the energy millions of miles later. It unlocks a Star
         | Trek, post-scarcity future that PV and wind cannot bring due to
         | their space requirements.
         | 
         | Also, you could eventually put one on a spaceship or other
         | planet. For that Star Trek future.
        
         | galuano1 wrote:
         | Predictable and abundant supply of fuel, and hopefully greener
         | to produce the powerplant itself.
        
         | vfclists wrote:
         | Industry does not run on solar and wind and sad to say it,
         | current storage energy is not green.
         | 
         | The cleanest energy available now is nuclear fission, but there
         | is no money in it for the energy industry. It is too plentiful
         | and cheap if implemented properly and capitalism does not like
         | plentiful and cheap.
         | 
         | France has had cheap electricity for decades and it seems it
         | has been so cheap that they don't want it anymore.
         | 
         | This is all capitalist boondoggles.
        
       | trhr wrote:
       | I have an idea. Why don't we just take all the nuclear weapons
       | we've accumulated around the planet and explode them in the South
       | China Sea?
        
       | rcgorton wrote:
        
       | MrFoof wrote:
       | I'm glad we might see fission power plants in my lifetime (next
       | 30-50 years). My father still finds it novel that he basically
       | gets to wear Dick Tracy's watch.
       | 
       | Yet I'm concerned that shortly thereafter, the giant robotic
       | laser death spiders will destroy entire cities. This might also
       | be be before we've built the arcologies to launch into outer
       | space to escape the giant robot laser death spiders.
        
         | pmarreck wrote:
         | > fission power
         | 
         | you probably meant "fusion"
         | 
         | > My father still finds it novel that he basically gets to wear
         | Dick Tracy's watch.
         | 
         | Well, except for the front-facing camera, but that's trivial to
         | add at this point. And as a 50 year old, I agree. I feel like
         | being incarnated in '72 has gotten me ethereal tickets to the
         | greatest technological expansion/brouhaha in all of human
         | history, and I don't know what my soul did to deserve this
         | pleasure. Everything I've been into as a kid "before it was
         | cool" has absolutely exploded: Computers, electronic music,
         | gaming, telecom, AI, green energy/electric cars... but also
         | science, medicine, etc. are making tremendous progress (I'm
         | down 35 lbs thanks to Mounjaro, a brand new drug). Hell, even
         | that weird side interest in UFO's (one of the first sections of
         | the library I discovered as a kid) has paid dividends with the
         | USG finally admitting they're real. BRB, I have to pinch
         | myself. Unironic "what a time to be alive"!
         | 
         | > giant robot laser death spiders
         | 
         | you should probably worry more about the silent airborne drone
         | army suicide bombers first. (What was the movie that actually
         | featured a scene with those, btw? I think it had Morgan
         | Freeman? EDIT: Found it, thanks to those other technological
         | wonders, Google and YouTube:
         | https://www.youtube.com/watch?v=40JFxhhJEYk)
         | 
         | There will always be dangers with progress. Two steps forward,
         | one step back. But I leave you with this. I asked ChatGPT to
         | summarize this article as a sarcastic poem
         | https://newsletter.mollywhite.net/p/everything-sam-bankman-f...
         | and here's what it gave me, and I'm still chuckling about how
         | awesome this is:
         | 
         | Sam Bankman-Fried talks a lot
         | 
         | But it's all just hot air
         | 
         | He tries to seem transparent
         | 
         | But he's just trying to repair
         | 
         | His reputation, once so grand
         | 
         | Is now as tarnished as can be
         | 
         | He's just a fraud, don't be fooled
         | 
         | By his attempts at publicity.
        
           | MrFoof wrote:
           | Yes, fusion. I 1000% blame mobile autocorrect.
           | 
           | > What was the movie that actually featured a scene with
           | those, btw? I think it had Morgan Freeman
           | 
           | It was specifically a SimCity 2000 reference.
        
             | pmarreck wrote:
             | I played Simcity 2K and apparently completely forgot that
             | "disaster" sorry lol
        
           | anotherman554 wrote:
           | The original Dick Tracy Watch introduced in 1946 didn't have
           | a camera. A newer model featuring a camera came out in a 1964
           | comic.
           | 
           | I haven't read Dick Tracy in a long time, but if it's still
           | being made I bet Tracy's watch has been upgraded with a bunch
           | of new features the Apple Watch lacks.
        
             | pmarreck wrote:
             | I did not know that!
        
       | jkelleyrtp wrote:
       | > LLNL's experiment surpassed the fusion threshold by delivering
       | 2.05 megajoules (MJ) of energy to the target, resulting in 3.15
       | MJ of fusion energy output, demonstrating for the first time a
       | most fundamental science basis for inertial fusion energy (IFE)
       | 
       | Yesterday, everyone was complaining about the 2.2:2.0 ratio, but
       | now we're working with 3.15:2.05.
       | 
       | With modern lasers, that'd be a total Q of 0.375 assuming 100%
       | efficiency through direct-energy-capture.
       | 
       | The jumps to get here included
       | 
       | - 40% with the new targets
       | 
       | - 60% with magnetic confinement
       | 
       | - 35% with crycooling of the target
       | 
       | The recent NIF experiments have jumped up in power. The first
       | shot that started this new chain of research was about 1.7 MJ of
       | energy delivered. Now, 2.15 MJ. However, the output has jumped
       | non-linearly, demonstrating the scaling laws at work.
       | 
       | > I've helped to secure the highest ever authorization of over
       | $624 million this year in the National Defense Authorization Act
       | for the ICF program to build on this amazing breakthrough."
       | 
       | It's nice to see this milestone recognized, even if the funding
       | it still rather small.
        
         | rsync wrote:
         | "Yesterday, everyone was complaining about the 2.2:2.0 ratio,
         | but now we're working with 3.15:2.05."
         | 
         | What is the difference between todays announcement and
         | yesterdays ?
         | 
         | I thought we were just getting re-submitted headlines, but
         | apparently this news is different than yesterday ?
        
           | highwaylights wrote:
           | Speculation.
           | 
           | People believed that X:Y was 2.2:2.0, but it's now 3.15:2.05.
           | 
           | The 10% EROI apparently wasn't impressive enough, it's now
           | 54% EROI on paper (assuming less because of capture
           | inefficiencies).
           | 
           | I'm no expert, but theoretically my understanding is that
           | this ratio should scale along this same pattern for higher
           | values of Y.
        
             | zbobet2012 wrote:
             | The X:Y ratio should increase for high values of Y in ICF.
             | See https://suli.pppl.gov/2019/course/SULI2019_IntroICF_TMa
             | _2019...
        
           | yk wrote:
           | Yesterdays news was that this result was leaked to the FT
           | with apparently preliminary numbers. And today there was a
           | press conference that had somewhat better looking numbers.
        
           | adrianmonk wrote:
           | The official announcement (with the real info) was this
           | morning.
           | 
           | Before that, the only official word was that an announcement
           | was coming, and all the info was unofficial leaks and rumors.
        
         | IgorPartola wrote:
         | I keep getting lost in the numbers here. What was the net
         | gain/loss for the entire system? Without the "lasers are 1%
         | efficient at 20% energy loss with 40% energy transfer loss" and
         | all that.
        
           | joosters wrote:
           | They needed roughly 500MJ of energy to power the lasers and
           | produce the 2.5MJ of energy, so the net loss was... about
           | 500MJ.
        
           | zbobet2012 wrote:
           | The net gain of the entire system at NIF doesn't matter,
           | because the system at NIF was never designed to make a net
           | gain.
           | 
           | People are estimating how this result moves the equation for
           | an overall system that is designed for power production. Most
           | numbers I have seen still leave a theoretically optimal power
           | plant producing around a 30% loss in power with this number.
        
           | nine_k wrote:
           | _AFAICT:_ There 's a large net gain compared to the energy
           | emitted by the lasers. There is still a considerable loss
           | compared to the energy consumed by the lasers.
           | 
           | While at it: I don't think the NIF approach will ever be
           | applicable to commercial power generation on Earth. But I
           | hope it will be one day applicable to a fusion-based rocket
           | engine.
        
             | jackmott wrote:
        
         | nothis wrote:
         | Naive question: Once they get out more than they spend, can
         | they just loop the generated energy back in and keep increasing
         | this exponentially?
        
         | w0mbat wrote:
         | Their total power draw from the grid was 300 megajoules and
         | they got back about 3 megajoules, so don't start celebrating
         | yet. Source: New York Times.
        
           | naikrovek wrote:
           | don't you think it's nuts that your arrogance would have you
           | believe that the people on the ground doing the experiment
           | know less about the power consumption and output than you do?
           | Because I do.
           | 
           | There's a lot of supporting stuff as well as energy to drive
           | that stuff that goes into leading edge tech development like
           | this, that does not matter in terms of the reaction itself.
           | 
           | If they say they achieved more output than input, then I will
           | believe them over a random HN comment snob _any day of any
           | week._
        
             | Retric wrote:
             | The paper was very clear what was involved and that
             | information was poorly communicated. The experiment used X
             | energy from a laser pulse to get Y thermal energy. The
             | issue w0mbat referred to is to be self sustaining you need
             | to use the output energy to drive the process. Aka the
             | important number is after all relevant losses including
             | electricity > lasers > fusion > heat > electricity, with
             | each of those stages have losses. The reason they don't
             | communicate end to end efficiency is from a scientific
             | standpoint it's meaningless as they aren't converting any
             | thermal energy into electricity.
             | 
             | For example p + p Fusion releases neutrinos which then
             | escape any practical device without depositing their energy
             | as heat. This isn't a concern with DT fusion but again the
             | point is we don't really care about the actual mass to
             | energy conversion but rather the amount of useful energy
             | obtained.
        
               | naikrovek wrote:
               | none of what anyone said is about a self-sustaining
               | reaction.
               | 
               | this is about more power leaving the reaction chamber
               | than what entered it. _that 's all_ the announcement is
               | about.
               | 
               | this is NOT about how much energy it takes to ready the
               | lasers. this is NOT about the electricity consumed by
               | lighting, computers, cooling, or measurement or anything
               | else-- none of that counts when you are measuring the
               | efficiency of the reaction itself.
               | 
               | this is about more energy leaving the reaction chamber
               | than went in.
               | 
               | understanding that is key to understanding the
               | significance of the announcement, and this is
               | significant.
               | 
               | and I maintain that the poster I originally called
               | arrogant is arrogant, because they indicated in their
               | comment that they knew how to calculate reaction
               | efficiency better than the physicists doing the work. I
               | called it arrogant because it is --objectively-- an
               | arrogant position to take.
               | 
               | if that makes _me_ arrogant, then so be it. my arrogance
               | is independent of theirs and has no bearing on comments
               | made before my own, and my comment did not influence
               | theirs. (they were being arrogant before I pointed it
               | out.)
        
               | Retric wrote:
               | > none of what anyone said is about a self-sustaining
               | reaction.
               | 
               | Actual power plants are self sustaining as in they use
               | the electricity they produce to operate, it's mandatory
               | though not sufficient for any commercial fusion power
               | plant.
               | 
               | So, this isn't about a different way to "calculate
               | reaction efficiency better than the physicists doing the
               | work" he was directly quoting their numbers from the
               | paper. It's only a question of communicating the meaning
               | of efficiency.
               | 
               | > this is about more energy leaving the reaction chamber
               | than went in.
               | 
               | The exact same energy was there before and after fusion
               | only it's form changed. It might seem pedantic to point
               | that out, but if you don't make it clear people will
               | misunderstand.
               | 
               | Also, the applied laser energy also leaves the reaction
               | chamber so any fusion would be net positive thermal
               | energy by that yardstick.
        
               | r2_pilot wrote:
               | > Actual power plants are self sustaining Actual power
               | plants are not necessarily self-sustaining and
               | practically none of them can start if the grid power is
               | not available. See: black start power plants and
               | https://youtu.be/uOSnQM1Zu4w
        
               | [deleted]
        
               | Retric wrote:
               | If it on average produces _less_ electricity than it
               | consumes then it isn't a power plant.
               | 
               | Black start is obviously a different question than being
               | self sustaining.
        
             | qwytw wrote:
             | I'm sorry but you sound much more arrogant here with your
             | strange assumptions. AFAIK all of those things he said are
             | based on the data from the experiment. And I've read the
             | same (i.e. that it's very far from being energy efficient).
             | 
             | > will believe Wouldn't be better if you were able in to
             | verify stuff to some degree yourself instead blindly
             | trusting every expert (not at all implying that the people
             | who did this experiment are untrustworthy but your bound to
             | run into some bad apples with this attitude eventually)
        
           | poopbutt6 wrote:
           | I agree! These results are NO cause for celebration. To do so
           | would be deliberately misleading, and potentially devalue
           | celebrations in general.
        
           | teilo wrote:
           | Now add in the 50% efficiency of conversion of heat to
           | electricity (and that's very optimistic), and it's only 1.5
           | megajoules, or 0.5%, right where I calculated it based on
           | initial information.
           | 
           | IANAP, but I see no path forward to sufficient Q-total using
           | plasma fusion to put this to any practical use. Unless the
           | reaction can somehow be self-sustaining, I do not believe
           | this will ever work.
        
           | cheriot wrote:
           | I think the "With modern lasers" part is addressing that.
        
           | floxy wrote:
           | I guess we should take this as a lesson in communications.
           | The "breakeven" thing is a red-herring that should have been
           | have been left out of the message, or at least only mentioned
           | as a footnote. The critical ELI5 message that should have
           | been presented is that they used a laser to create some tiny
           | amount of fusion. But we have been able to do that for a
           | while now. The important thing is that they were then able to
           | use the heat and pressure of the laser generated fusion to
           | create even more fusion. A tiny amount of fusion creates even
           | more fusion, a positive feedback loop. The secondary fusion
           | is still small, but it is more than the tiny amount of laser
           | generated fusion. The gain is greater than one. That's the
           | important message. And for the future, the important takeaway
           | is that the next step is to take the tiny amount of laser
           | fusion to create a small amount of fusion, and that small
           | amount of fusion to create a medium amount of fusion. And
           | eventually scale it up enough that you have a large amount of
           | fusion, but controlled, and not a gigantic amount of fusion
           | that you have in thermonuclear weapons, or the ginormous
           | fusion of the sun.
        
             | eru wrote:
             | > [...], or the ginormous fusion of the sun.
             | 
             | The sun actually has very little fusion per cubic metre or
             | per kg.
             | 
             | Per volume the core of the sun produces only a quarter of
             | the heat of the human body (and per kg it's even less,
             | owing to high density).
             | 
             | That's why our fusion reactors can't just mimic stars, they
             | have to far surpass them to be useful to us.
        
               | samvher wrote:
               | Can you say more about the ways in which fusion reactors
               | need to surpass stars, and why people believe it's
               | feasible that we can sufficiently get to that point?
               | 
               | (Also - thanks for sharing one of the most interesting
               | comments I've read on the internet in quite a while.)
        
               | epgui wrote:
               | The per-volume claim rings alarms in my head.
               | 
               | If it produced a quarter of the heat of the human body
               | per volume, its temperature would be lower as well (less
               | than 37 degrees Celsius).[1] This is obviously not the
               | case.
               | 
               | [1] Obviously heat and temperature are not the same, I
               | know that. But when something's temperature is higher
               | than another thing's, then heat is exchanged along that
               | gradient. Meaning if the sun produced less volumetric
               | heat than the human body, a human body placed within the
               | sun would warm the sun and cool the human.
        
               | bzbarsky wrote:
               | Heat and temperature are indeed not the same.
               | 
               | For both the sun and a human on earth there are two
               | processes going on:
               | 
               | 1. Heat production per unit volume.
               | 
               | 2. Heat loss per unit surface area.
               | 
               | The volume to surface area ratio for the sun is much
               | larger than for the human, for a minor reason (the sun is
               | a sphere) and a major reason (the sun's linear size is
               | much bigger). So the equilibrium temperature of the sun
               | in the same ambient outside environment is higher than
               | the human's.
               | 
               | Your thought experiment about placing a human inside the
               | sun would in fact work as you say, if a human body
               | continued to produce heat once it had achieved thermal
               | equilibrium with the surrounding plasma.
        
               | hatsunearu wrote:
               | Yeah, this is a morbid analogy but if you got a bunch of
               | people enclosed in a small area, the people in the middle
               | will get so hot they will heatstroke, even if it's
               | freezing outside. See the recent Korean crushing
               | disaster.
        
               | aoetalks wrote:
               | This is incredible.
        
               | eru wrote:
               | To give some more detail: hydrogen to helium fusion (even
               | with intermediate steps) is extremely unlikely to happen.
               | That's part of why the sun will last for billions of
               | years. And that's also why first human attempts at fusion
               | are not trying to use straight up hydrogen as the fuel.
               | 
               | Good old Wikipedia has this gem:
               | 
               | > The large power output of the Sun is mainly due to the
               | huge size and density of its core (compared to Earth and
               | objects on Earth), with only a fairly small amount of
               | power being generated per cubic metre. Theoretical models
               | of the Sun's interior indicate a maximum power density,
               | or energy production, of approximately 276.5 watts per
               | cubic metre at the center of the core,[63] which is about
               | the same power density inside a compost pile.
               | 
               | https://en.wikipedia.org/wiki/Sun#Core
               | 
               | Another fun fact: there's a decades old design for a
               | gadget that fits at the top of your desk and does nuclear
               | fusion. You could build one yourself, if you are
               | sufficiently dedicated. Unfortunately, no one has ever
               | worked out how to run one of them as a power plant. Ie
               | how to get more useful energy out than you have to put
               | in.
               | 
               | https://en.wikipedia.org/wiki/Fusor
        
               | PaulHoule wrote:
               | Those Fusors can make a decent neutron source however.
               | Those were invented by Philo Farnsworth, who invented the
               | cathode ray tube for television.
        
               | dr_dshiv wrote:
               | I'm so disappointed I can't just buy a fusor online.
               | 
               | But here is a MAKE magazine article explaining how to
               | build! https://makezine.com/projects/nuclear-fusor/
        
               | [deleted]
        
               | throw827474737 wrote:
               | That, but also mimicing the pressure of the sun here is
               | just not possible (yet? :D), why we need to play with
               | higher temperaturs with different problematic
               | consequences.
        
               | [deleted]
        
               | cloudhead wrote:
               | How is the sun so hot then?
        
               | bzbarsky wrote:
               | Total power radiated by a black body per unit surface
               | area scales as T^4 (in Kelvin).
               | 
               | So for black bodies with identical shape and linear
               | dimensions R1 and R2, with identical power production per
               | unit volume, both in thermal equilibrium with whatever is
               | outside them, you would expect:
               | 
               | R1/R2 = (T1/T2)^4
               | 
               | (because setting power produced equal to power radiated
               | gives R proportional to T^4).
               | 
               | Pretending humans are spheres with radius 1m and the sun
               | is a sphere with radius 7*10^8m, you would expect the sun
               | to have ~160 times the temperature of a human at
               | equilibrium in vacuum. It's going to be lower because not
               | all of the sun is power-producing, of course. But higher
               | because a human is not 1m in radius. And again higher
               | because humans are not spheres and lose heat more than a
               | sphere would for the same volume (more surface area).
               | 
               | The sun is about 6000K on the surface. That would give us
               | ~40K for the equilibrium temperature of a human in
               | vacuum, which at least seems truthy.
               | 
               | TL;DR: the sun is big, with a small surface area compared
               | to its volume, because it's big.
        
               | martopix wrote:
               | Presumably it's so big that this amount adds up, and it's
               | sufficiently isolated to heat up without losing too much
               | power towards the outside
        
             | jboy55 wrote:
             | and not a gigantic amount of fusion that you have in
             | thermonuclear weapons,
             | 
             | Ironically, this experiment was designed primarily to
             | simulate the fusion you have in thermonuclear weapons.
             | That's the NIF's purpose and the purpose of this
             | experiment. From Nature
             | https://www.nature.com/articles/d41586-022-04440-7
             | 
             | "Herrmann acknowledges as much, saying that there are many
             | steps on the path to laser fusion energy. "NIF was not
             | designed to be efficient," he says. "It was designed to be
             | the biggest laser we could possibly build to give us the
             | data we need for the [nuclear] stockpile research
             | programme."
        
               | _cs2017_ wrote:
               | How would it help build better weapons? I thought the
               | existing thermonuclear bombs do the job perfectly fine.
               | Sure, the military might want to make them a bit smaller
               | or a bit cheaper, but is it really such a big deal as to
               | warrant a major announcement?
        
               | bunabhucan wrote:
               | "Nuclear stockpile research" is only making weapons
               | "better" in the sense that they are reliable despite not
               | having been tested in decades. There's probably a
               | component of "unemployed nuclear weapons designers is a
               | bad thing" also.
               | 
               | The fusion for power experiments are using the same laser
               | equipment but different targets and sensors.
        
               | jboy55 wrote:
               | I wonder if they achieved a high Q value decades ago, but
               | using the targets more inline with the bomb materials.
        
               | njarboe wrote:
               | The DOD also probably likes having some nuclear weapons
               | designers available on short notice
        
               | User23 wrote:
               | The USA no longer has the technical capability to
               | manufacture the necessary parts to maintain the current
               | stockpile. The whole strategic arms reduction treaty
               | regime is basically a fig leaf to cover for the fact that
               | we have to cannibalize some legacy weapons to maintain
               | the rest. If nothing changes the USA probably won't have
               | an effective arsenal within a century. Given the likely
               | state of the USA by that time, that's probably for the
               | best.
        
               | _cs2017_ wrote:
               | Interesting, but:
               | 
               | 1. How does this research help address this problem?
               | 
               | 2. What are the sources for your opinion?
        
               | User23 wrote:
               | > 1. How does this research help address this problem?
               | 
               | I see it the other way around, this problem makes me
               | doubt that this research will ever actually lead
               | anywhere, supposing it's even as good a result as it
               | first appears.
               | 
               | > 2. What are the sources for your opinion?
               | 
               | It's a fact. And my source is dead tree media. I don't
               | recall all the details, but there are some very finicky
               | parts that go into a state of the art warhead and we have
               | lost the capability to manufacture them. Is this really
               | so surprising? We can't even build new F-22s anymore!
        
               | jboy55 wrote:
               | The most famous key component that was speculated or
               | leaked, was that we lost the makeup and reason for the
               | Styrofoam that holds the primary and surrounds the
               | secondary.
               | 
               | This research successfully initiated fusion, using a
               | capsule of hydrogen made of some material, surrounded by
               | something, with an outer layer. This outer layer is
               | turned into X-Rays by the laser, which then ablate the
               | hydrogen capsule's casing casing the inwards pressure.
               | You could speculate, that they just found the makeup for
               | something that would replace the Styrofoam, or we just
               | improved upon it.
        
               | jdhendrickson wrote:
               | This is incorrect.
               | 
               | Similar to the "we can't make concrete as good as the
               | romans" line of woo. Caveat Emptor
        
               | pauljurczak wrote:
               | > USA probably won't have an effective arsenal within a
               | century.
               | 
               | If other countries joined, it would be a great outcome.
        
               | kubanczyk wrote:
               | > > USA probably won't have an effective arsenal within a
               | century.
               | 
               | > If other countries joined, it would be a great outcome.
               | 
               | Why the optimism? Without MAD, it's nearly certain that
               | we'd have a world war at some point in time. Sooner or
               | later, it will surely happen. If you think it won't
               | happen, or won't cost millions of lives, or won't employ
               | re-developed nukes eventually, please tell me why you
               | think so. (No sarcasm.)
        
               | scoopertrooper wrote:
               | I don't think MAD is all that effective. At this moment
               | in time we're seeing:
               | 
               | * Several concurrent arms races in the Middle East, Asia,
               | and Europe
               | 
               | * A high intensity conflict in Ukraine
               | 
               | * China threatening a land invasion into Taiwan
               | 
               | MAD might be preventing a country like Poland from
               | jumping into the Ukraine conflict, but more likely it's
               | because of its involvement in NATO.
               | 
               | I think collective security organisations are a far more
               | potent force for peace than nuclear weapons. If countries
               | abided by their security agreements in WW2, then we'd
               | have nipped the entire thing in the bud.
        
               | [deleted]
        
               | kubanczyk wrote:
               | MAD means that the leaders _know_ they risk their own
               | lives. That 's the elephant in the room.
               | 
               | Before MAD, for thousands of years, all the big
               | populations were shaped/educated/pushed into limitless
               | sacrifice for the motherland.
               | 
               | > collective security organisations are a far more potent
               | force for peace than nuclear weapons
               | 
               | I think if you take MAD away, the "collective security
               | organisations" would quickly break into good ol'
               | alliances.
        
               | njarboe wrote:
               | For most of the thousands of years of warfare kings their
               | armies into battle. Only in the last 500 years or so has
               | that changed
        
               | lucumo wrote:
               | > I don't think MAD is all that effective. At this moment
               | in time we're seeing: > * Several concurrent arms races
               | in the Middle East, Asia, and Europe > * A high intensity
               | conflict in Ukraine > * China threatening a land invasion
               | into Taiwan
               | 
               | I mean... Only one of those is an actual fight. And there
               | MAD doesn't apply because the defender doesn't have the
               | Assured Destruction capability needed.
        
               | User23 wrote:
               | > Several concurrent arms races in the Middle East, Asia,
               | and Europe
               | 
               | Which is to say, possible future proxy wars between the
               | great powers where MAD will supposedly restrict conflict
               | intensity. See below.
               | 
               | > A high intensity conflict in Ukraine
               | 
               | What's going on in Ukraine is a bog standard cold war
               | style proxy war. The NATO plan is basically to turn it
               | into another Afghanistan for the Russians. It's the exact
               | thing that MAD is meant to keep from spilling over into a
               | world war between the principals.
               | 
               | > China threatening a land invasion into Taiwan
               | 
               | This is more interesting. US conventional forces almost
               | certainly have no hope of beating China that close to
               | home. Therefore, any effective US response would require
               | nuking China and China is presumably deterring that with
               | their nukes. There is an argument to be made here that a
               | non-nuclear Chinese military would be in Taiwan's best
               | interests. However, I see no scenario where either a
               | nuclear or non-nuclear China and a non-nuclear USA is in
               | Taiwan's best interests. So while the MAD case isn't the
               | best case for Taiwan here, it's also not the worst.
        
               | basilgohar wrote:
               | There are a lot more armed conflicts throughout the world
               | that are proxies or partial proxies between the various
               | powers in the world (US, Russia, and more). See Yemen,
               | Syria, and many more throughout Africa. World powers tend
               | to get on one side or another as they see their interests
               | align and oftentimes this prolongs the conflict rather
               | than bring it to any resolution.
        
               | speeder wrote:
               | I guess they also don't want to blow up random civilians
               | by accident again.
               | 
               | When castle bravo was tested, we didn't knew that
               | lithium7 fusion was possible and that it would generate
               | energy. The bomb had a lot of lithium7 because it was
               | cheaper than lithium6. Castle Bravo then proceeded to
               | explode with way more power than intended, it vaporized
               | the measurement instruments, ruined the test site,
               | damaged civilian property and caused a horrible amount of
               | fallout that screwed a enormous amount of people from
               | more than one country.
               | 
               | Even during war, I suppose you want your explosions to
               | behave in the way you expect... so you need to figure out
               | all the physics related to them.
        
               | metadat wrote:
               | More on Castle Bravo:
               | https://en.wikipedia.org/wiki/Castle_Bravo
        
               | atemerev wrote:
               | To learn about their degradation modes and how to
               | maintain them (since full-scale nuclear tests are now
               | verboten, and subcritical experiments only deal with
               | fission part of the entire assembly -- we now also need
               | some experimental setup to test the fusion part:
               | radiation pressure, X-ray reflection, ablation modes etc.
               | NIF is this setup).
               | 
               | Also, there is a constant need to improve fusion/fission
               | rate in the total energy output, and perhaps eventually
               | design pure fusion weapons, though this is still probably
               | out of reach.
        
               | jacquesm wrote:
               | Given the limitations on nuclear research for weapons
               | purposes any information that can be gleaned from these
               | experiments that is 'dual use' is more than welcome with
               | the parties that are currently stymied by various arms
               | control agreements. This is also why you will see a lot
               | of supercomputer capacity near such research, it allows
               | simulation of experiments with high fidelity rather than
               | the experiments themselves. These are all exploitation of
               | loopholes. The biggest value is probably in being able to
               | confirm that the various computer models accurately
               | predict the experimental outcomes. This when confirmed at
               | scale will allow for the computer models to be used for
               | different applications (ie: weapons research) with a
               | higher level of confidence.
        
               | _cs2017_ wrote:
               | Presumably these computer models are mostly useful for
               | creating new designs (since the old designs were proven
               | by real tests). Would such new designs be convincing
               | enough to the adversary to fulfill its role as a
               | strategic deterrence?
               | 
               | When (in XX years?) almost all US nukes are only
               | simulated on computers and not actually tested, the
               | Russians may start wondering if the US aresnal actually
               | works, no? That would be a horrible outcome, since it
               | means the Russians would be taking somewhat greater risks
               | in their decision-making. Wouldn't far outweigh any
               | opertaional or financial benefits the newer designs
               | offer?
               | 
               | I suppose one could argue that if the loss of confidence
               | in strategic weapons matched the actual loss in
               | reliability, it might be a "no op" (although even this is
               | arguable). But if the Russians think the US simulations
               | suck, while the US is actually building really good
               | simulations, the loss of confidence would be greater than
               | the actual loss in reliability. In the extreme case, the
               | nukes work great, but everyone thinks they are scrap
               | metal.
               | 
               | Of course, the same happens in reverse: if the Russians
               | are upgrading their weapons to untested designs, the US
               | may start underestimating the risk.
        
               | jacquesm wrote:
               | > the Russians may start wondering if the US aresnal
               | actually works, no?
               | 
               | If anything the last year or so has probably made the
               | reverse happening and the US and its adversaries likely
               | both have very high confidence in that the US arsenal
               | actually works.
        
               | jboy55 wrote:
               | Or the US finds that after x many years bombs degrade in
               | unexpected ways, and that while we were able to figure
               | this out and fix it. Then we speculate that the Russians
               | probably haven't fixed theirs in the same way and their
               | bombs aren't good anymore. Which means the risk of a
               | nuclear war just jumps up, since MAD is compromised.
        
               | prpl wrote:
               | experimental verification of models with actual materials
               | used in existing bombs, for one.
        
               | dmix wrote:
               | From what I can tell this is mostly a useful cover story
               | as a fallback for the moon-shot type energy potential.
               | But are there serious downsides to having this be the
               | case? Does it significantly distract away from the
               | pursuit of energy? Or somehow fundamentally constrain the
               | projects scope?
        
               | moloch-hai wrote:
               | Exactly the opposite: their task, assigned by Congress,
               | is _weapons work_. Period.
               | 
               | But pretending to work on "carbon-free energy" is good
               | for funding, _just now_. Four years ago, being all about
               | weapons opened the tap.
               | 
               | Make no mistake, there is no story here. There will be
               | _no_ "unlimited free energy" from this, or any other
               | fusion project. The fusion startups are spending down
               | investors' money with zero possibility of payback (Helion
               | conceivably excepted), because if they did get Q>1, they
               | have no workable way to harness it. ITER will not even
               | try to produce one watt-second of electricity. Its
               | follow-on demo reactor won't _start_ building until 2050,
               | _if not further delayed_.
               | 
               | We know the way to get unlimited free energy: solar.
               | Build more, get more. It doesn't have bomb scientists
               | making inflated claims; it just works, and better every
               | year.
        
               | xbmcuser wrote:
               | If they can get a continuous fusion reaction going
               | converting the heat energy from that to electricity won't
               | be a problem. Getting a contained fusion reaction that
               | gives out more energy than input is the problem how to
               | convert that into electricity is not going to be a
               | problem.
        
               | moloch-hai wrote:
               | It doesn't make heat. It makes fast neutrons. Turning
               | them into usable heat is a project of its own.
               | 
               | Turning dumb heat into electric power is expensive.
               | Nothing that depends on doing that can ever compete with
               | wind and solar, anymore.
               | 
               | Tritium doesn't grow on trees. Making it by blasting
               | those hot neutrons into a thousand tons of FLiBe is easy
               | enough. Getting your few grams a day, at PPB
               | concentration, out of that thousand tons of stuff is...
               | nobody has any idea how. But you need to, to have fuel
               | for tomorrow.
               | 
               | No, there won't be any of that. It would be
               | _fantastically_ more expensive than fission. Fission is
               | not competitive, and gets less so by the day. Fusion is
               | nothing but a money pit (with the just barely-possible
               | exception of D-3He).
        
               | zbobet2012 wrote:
               | You've been all over this thread with some aggressive
               | takes that are pretty seriously not supported.
               | 
               | > Turning dumb heat into electric power is expensive.
               | Nothing that depends on doing that can ever compete with
               | wind and solar, anymore.
               | 
               | This isn't even strictly true today when focusing on
               | current "dumb heat sources":
               | 
               | https://en.wikipedia.org/wiki/Cost_of_electricity_by_sour
               | ce#...
               | 
               | "cost of extension of operations of existing nuclear
               | power plants (LTO, long-term operations) has the lowest
               | LCOE of low-carbon energy sources; "
               | 
               | I'm going to go with the OECD and NEA on this one.
               | 
               | > Tritium doesn't grow on trees.
               | 
               | https://en.wikipedia.org/wiki/Breeding_blanket
               | 
               | Saying that there are unknown engineering challenges is
               | kind of a "duh", otherwise we wouldn't be researching we
               | would be implementing. As you also mentioned there are
               | other alternatives which we could consider than tritium.
               | 
               | > Fission is not competitive, and gets less so by the
               | day.
               | 
               | https://www.sciencedirect.com/science/article/abs/pii/S03
               | 062... yeah that's not true
               | 
               | > Fusion is nothing but a money pit (with the just
               | barely-possible exception of D-3He).
               | 
               | We genuinely don't know if fusion is a money pit or not,
               | because we don't have any idea how much a successful form
               | will cost. Tritium blankets may be easy or not. Maybe
               | helion's D-3HE will have a breakthrough. Maybe it's ICF.
               | 
               | I've not seen suggestions by anyone that wind and solar
               | build-outs stop, or get diminished. Indeed at this point
               | because the cost are low, industry will continue to
               | invest in them regardless.
               | 
               | However, we will need a lot more energy production than
               | folks think. We need to decarbonize the atmosphere. And
               | that's going to require a lot of power.
               | 
               | All that aside, solar and wind are not getting you to
               | mars in a timely fashion. We have reasons to research
               | fusion that escape large commercial power generation.
        
               | moloch-hai wrote:
               | Cost of solar and wind are still plummeting. Anything
               | that can match them today won't tomorrow. OECD and NEA
               | agree.
               | 
               | Not going to Mars sounds like a great plan. Sign me up!
        
               | vixen99 wrote:
               | We certainly need a lot more energy production but to
               | decarbonize the atmosphere there has be a target level
               | with an evidential basis on which to proceed. If it's
               | considered (as by many) that we have a _climate
               | emergency_ (though this is not reported at all in the
               | IPCC report) then any decarbonization at all will
               | obviously serve for starters. If this is not the case
               | then there are other considerations such as the fact that
               | as CO2 levels have risen so has global food production -
               | about 30% over the last 30 years.
               | 
               |  _Simulations with multiple global ecosystem models
               | suggest that CO2 fertilization effects explain 70% of the
               | observed greening trend, followed by nitrogen deposition
               | (9%), climate change (8%) and land cover change (LCC)
               | (4%). CO2 fertilization effects explain most of the
               | greening trends in the tropics, whereas climate change
               | resulted in greening of the high latitudes and the
               | Tibetan Plateau._.
               | https://sites.bu.edu/cliveg/files/2016/04/zhu-greening-
               | earth...
               | 
               | This is not a surprise given that carbon is needed for
               | plant growth, a fact well understood by commercial
               | growers who pipe CO2 into their greenhouses. So one issue
               | might be, if decarbonization is successful then what
               | might be the acceptable level of reduction in global food
               | supply?
               | 
               | Another issue relates to temperature. From an analysis of
               | 974 million deaths in 384 locations across 13 countries
               | it's been concluded that twenty times more people die
               | from the cold as from the heat.https://composite-
               | indicators.jrc.ec.europa.eu/sites/default/... A recent
               | paper (Dec 12 2022) regarding heart attacks states
               | "extreme temperatures accounted for 2.2 additional deaths
               | per 1,000 on hot days and 9.1 additional deaths per 1,000
               | on cold days." Circulation.
               | doi.org/10.1161/CIRCULATIONAHA.122.061832.
               | 
               | Do any of the reports present an ethical problem? No,
               | they do not given an extreme interpretation of climate
               | models.
        
               | jacquesm wrote:
               | > If they can get a continuous fusion reaction going
               | converting the heat energy from that to electricity won't
               | be a problem.
               | 
               | Even accepting the qualification that's not just a mere
               | matter of engineering, capturing that heat from a source
               | that hot is not without trouble. A bit like how there is
               | plenty of energy in a single lightning strike and yet we
               | can't easily catch it even though in principle 'just
               | build a large enough capacitor and connect it to a
               | lightning rod' is a workable recipe.
               | 
               | > Getting a contained fusion reaction that gives out more
               | energy than input is the problem
               | 
               | Not in the least because the container itself is a very
               | hard problem to solve.
               | 
               | > how to convert that into electricity is not going to be
               | a problem.
               | 
               | It is _also_ a problem, albeit a lesser one.
               | 
               | The better way to look at all of these fusion projects is
               | a way to do an end run around arms control limitations
               | with as a very unlikely by-product the possible future
               | generation of energy. But I would not hold my breath for
               | that. Meanwhile, I'm all for capturing more of the energy
               | output by that other fusion reactor that we all have
               | access to, and learning how to store it over longer
               | periods. Preferably to start with a couple of days with
               | something that doesn't degrade (think very high density
               | super capacitor rather than a battery), but I'll take
               | advanced battery technology if it can be done cheap
               | enough per storage cycle. We're getting there.
        
               | dd36 wrote:
               | There's not plenty of energy in a lightning strike.
               | 
               | https://engineering.mit.edu/engage/ask-an-engineer/is-
               | there-...
        
               | HPsquared wrote:
               | Funnily enough it's about the same order of magnitude as
               | the fusion event discussed in this TFA: about 1 MJ.
               | 
               | Energy from one hohlraum [?] energy from two lightning
               | strikes
        
               | jboy55 wrote:
               | At least ITER has a plausible, in a sci-fi story sense,
               | way of creating a sustainable fusion reaction to which
               | more fuel could be given. The fact the neutrons produced,
               | if it did reach the high Q ratios, would irradiate and
               | break down everything involved, is probably 2070's
               | scientists and engineers problems to solve.
        
               | moloch-hai wrote:
               | In that paradise of abundant cheap solar and wind power,
               | only weapons people will be interested in fusion.
               | 
               | They will probably be trying to come up with zero-fallout
               | things they can use tactically.
        
               | zbobet2012 wrote:
               | Solar and wind power are not sufficient for spacecraft,
               | and many other applications. Fusion power still has very
               | interesting applications.
        
               | moloch-hai wrote:
               | Most likely, spacecraft will rely on power delivered via
               | laser.
               | 
               | If anybody succeeds in working out D-3He fusion, that
               | could work in a spacecraft. (D-T, no.) We could probably
               | scare up enough 3He to use for that, if there weren't too
               | many.
        
               | PaulHoule wrote:
               | If anybody in the universe is doing interstellar travel I
               | think they would have developed D-D fusion which is
               | somewhat more difficult than D-3He or D-T fusion but
               | probably possible with the a scaled up version of the
               | same machine.
               | 
               | Outside the frost line there is a lot of water and a
               | higher percentage of D relative to H so it seems possible
               | to "live off the land" between the stars without being
               | dependent on starshine. A D-D reactor would produce 3He
               | and T, a lot of those products would burn up in the
               | reactor because the reaction rates are high but it would
               | probably be possible to separate some of those out and
               | use it as a breeder reactor that makes fuel for D-3He and
               | D-T reactors elsewhere. I could picture the big D-D
               | reactor running on a large comet or dwarf planet like
               | Pluto producing D-3He for smaller reactors on spacecraft.
               | (D-T not only produces a lot of neutrons but the T has a
               | half life of 12 or so years and won't last for long
               | journies.)
               | 
               | My guess is that interstellar travelers would develop a
               | lifestyle that works around the frost line, where generic
               | bodies above a certain size have liquid water inside. If
               | they were grabby they might consume Ceres or Pluto but
               | might not really care about dry, idiosyncratic worlds
               | like the Earth and Mars.
        
               | rini17 wrote:
               | Solar is completely sufficient for 99% of applications.
        
               | iso1631 wrote:
               | How do you power a moon base with solar? 14 days of
               | battery?
               | 
               | Fine. How do you power a Europa base with Solar? A
               | Neptune probe?
        
               | rbanffy wrote:
               | > How do you power a moon base with solar? 14 days of
               | battery?
               | 
               | Either that or a place near one of the poles where you
               | get water _and_ lots of sunshine. A small fission reactor
               | is a handy thing to have, however.
               | 
               | > Fine. How do you power a Europa base with Solar?
               | 
               | A lot more solar panels, or wire loops harnessing
               | Jupiter's magnetic field and Europa's momentum, etc.
               | Fission is still cool for that.
               | 
               | > A Neptune probe?
               | 
               | Now we enter the nuclear fission territory. Maybe fusion,
               | some day.
        
               | floxy wrote:
               | >How do you power a moon base
               | 
               | For those interested in near term answer:
               | 
               | https://www.nasa.gov/mission_pages/tdm/fission-surface-
               | power...
        
               | rini17 wrote:
               | Since we're talking in present tense that's the remaining
               | 1%.
               | 
               | Moon base can be fine with power beamed from a satellite
               | or plain mirrors in orbit, no atmosphere in the way.
               | Might end up being still cheaper than hauling nuclear
               | reactor there plus all the infra to _reliably_ dump waste
               | heat from it.
        
               | iso1631 wrote:
               | "Solar and wind power are not sufficient for spacecraft"
               | 
               | I guess you're right that solar is useful for 99% of
               | spacecraft -- in that they use it currently. Not a very
               | useful observation
               | 
               | "and many other applications"
               | 
               | Power in polar regions. How well does Solar work in
               | Antarctica? Or Alaska for that matter?
        
               | moloch-hai wrote:
               | Laser beams from solar concentrators are likely until
               | aneutronic fusion pans out, _if ever_. Maybe after that,
               | too.
        
               | courgette wrote:
               | Honest question, because I want that to be true at scale.
               | 
               | Do we know how to store it properly yet? How does solar
               | pan out in case of surge ( eg : very cold winter night )
        
               | rini17 wrote:
               | I think parent was talking about space applications.
               | 
               | Anyway unlike fusion, seasonal thermal storage is viable
               | and available now, and will be scaled up in immediate
               | future. Also, with electrical vehicles inducing massive
               | investment into the grid, there will be both pressure and
               | resources to solve the rest.
        
               | aussieshibe wrote:
               | Why won't fusion still be a worthwhile goal even if we do
               | have abundant solar/wind?
               | 
               | Abundant and cheap are relative terms. Solar and wind
               | could be abundant in a "powers everything we have now and
               | for the foreseeable future of population growth" sense,
               | but maybe not in a "gigantic power-hungry megaprojects
               | which aren't remotely possible today" sense?
        
               | courgette wrote:
               | Also, is solar truly renewable ? Don't we need some rare
               | earth component to manufacture them.
               | 
               | What happen when we run out of that ?
        
               | moloch-hai wrote:
               | Solar needs _nothing_ that can be run out of. Likewise,
               | storage. There are plenty of lies repeated, about that
               | and about missing  "breakthroughs".
        
               | courgette wrote:
               | I do software for a living so that gives you my level of
               | ignorance of the real world.
               | 
               | I do have two question about solar
               | 
               | - is it "drivable" / "pilotable" ?
               | 
               | meaning reacting to surge in the grid? My understanding
               | is that this feature is highly desirable for a grid.
               | 
               | - can we actually build enough solar panel, physically ?
               | 
               | Don't we need some rare earth thingy that is not in
               | sufficient quantity on our planet as far as we know ? (
               | follow up : if there is enough, will there be enough in
               | 200 years ? )
        
               | GreymanTheGrey wrote:
               | In regards to your first question, the word you're
               | looking for in google-able energy industry jargon is
               | "dispatchable". And yes, dispatchability of intermittent
               | generation is achieved in a couple of ways in
               | contemporary electricity networks:                 1.
               | Deliberately backing off wind or solar generation from
               | full capacity to provide reserves for demand spikes,
               | transmission/generator outages, etc.  This means other
               | generation that may otherwise not have generated at all
               | over that period, is brought online to cover the
               | shortfall.            2. Co-locating grid-scale batteries
               | at intermittent generation sites ("hybrid generation
               | facilities" in energy industry jargon) to cover short-
               | term contingency events.
        
               | moloch-hai wrote:
               | The "rare-earths thingy" is a common, _transparent lie_
               | told frequently about both solar and wind. No rare-earths
               | are used in any solar panel. Some wind turbine generators
               | have used them, but not the big ones. And,  "rare-earths"
               | are not in fact rare. So, a double lie.
               | 
               | Solar panels provide cheap power generation on a
               | schedule. For dispatchability, you rely on storage. There
               | are many different kinds of practical, efficient storage;
               | which are used where will depend on local conditions.
               | Which will be cheapest isn't clear, but probably not
               | batteries. Batteries used won't need lithium, or rare-
               | earths, either
               | 
               | The lie most frequently repeated is that storage needs
               | some sort of "breakthrough". Second is that the small
               | amount built out means more than that there is not enough
               | renewable power yet to charge it from; when there is will
               | be time to build it. In the meantime, we fill in with NG
               | burning. The third is that "pumped hydro", the most
               | common used just now, needs "special geography". Hills
               | are very common.
               | 
               | The lie most frequently repeated about solar is that
               | there is any shortage of places to put it. It is most
               | efficiently floated on water reservoirs, where it cuts
               | evaporation and biofouling, although efficiency is only
               | one consideration. It shares nicely with pasture and even
               | crop land, cutting water demand and heat stress without
               | reducing yield.
               | 
               | There will never be any shortage of wind or solar: need
               | more, build more; materials needed are all abundant.
               | Likewise storage. Costs are still falling as fast as
               | ever, but are already lowest of any energy source ever
               | known.
        
               | zardo wrote:
               | > And, "rare-earths" are not in fact rare.
               | 
               | It's not a lie but is an unfortunate synonym. They are
               | rare in the sense that they are rarified, spread thin
               | everywhere not concentrated in ores.
        
               | rbanffy wrote:
               | > is probably 2070's scientists and engineers problems to
               | solve.
               | 
               | With some clever choices in building materials, we may be
               | able to dismantle ITER and its successors to use them as
               | fission fuels.
        
               | elihu wrote:
               | > The fusion startups are spending down investors' money
               | with zero possibility of payback (Helion conceivably
               | excepted), because if they did get Q>1, they have no
               | workable way to harness it. ITER will not even try to
               | produce one watt-second of electricity. Its follow-on
               | demo reactor won't start building until 2050, if not
               | further delayed.
               | 
               | You seem to be awfully certain of that. I'm not an expert
               | in this area, but my understanding is that the MIT Arc
               | reactor is planned to use FLiBe as a liquid coolant that
               | absorbs heat/neutrons/etc from the fusion reaction and is
               | pumped into heat exchangers to boil water to run
               | turbines. I mean, maybe there's some details not worked
               | out and maybe I'm misunderstanding how it works, but it
               | seems like a plan to generate electricity to me.
               | 
               | There's no plan to hook ITER up to a thermal plant
               | because it's a research reactor not a power plant, but
               | there's no conceptual reason they couldn't do it. (Not
               | that ITER is a great example; the design is already
               | antiquated before it's even finished.)
        
               | moloch-hai wrote:
               | "Some details"... Have you ever built anything?
               | 
               | Driving steam turbines, even with other costs at zero,
               | leaves you uncompetitive with renewables. But other costs
               | would be very, very far from zero. Extracting the grams
               | of tritium at PPB concentration dissolved in 1000 tons of
               | FLiBe every day so you have fuel for tomorrow is an
               | expensive job all by itself.
               | 
               | Making a whole new reactor every year or two because it
               | destroyed itself with neutron bombardment is another.
        
               | rnhmjoj wrote:
               | > There's no plan to hook ITER up to a thermal plant
               | because it's a research reactor not a power plant
               | 
               | Interestingly, that's not really true: IIRC the japanese
               | team working on the WCCB breeder module (that uses
               | supercritical water as coolant) plans on connecting the
               | water loop to a small turbine. If they succeed it would
               | be the first ever electrical power produced from fusion.
        
             | lazide wrote:
             | Eh, the 'mistake' was intentional, near as I can tell.
        
           | Trisell wrote:
           | If it takes 300 one time in the future to start a long term
           | reaction that's a price I think we would all pay. The fact
           | that we proved the idea now makes this just an engineering
           | problem.
        
             | NovaVeles wrote:
             | I'm not trying to undermine but more just act as a reminder
             | to some folk. There is no such thing as "just an
             | engineering problem". These things do not exist in a
             | vacuum. It is a part of the tripod of economics and
             | politics. If any one of these three buckles, the whole
             | thing doesn't happen. Concord was an engineering problem we
             | solved, but the economics and politics around it made it a
             | white elephant. Here's hoping this doesn't happen to this.
        
           | carabiner wrote:
           | They put 2.05 MJ in and got 3.15 MJ out. The 300MJ comes from
           | equipment inefficiency- remember this is a research facility
           | to prove plasma physics and ignition itself, mainly designed
           | for weapons research. The fact they got definite fusion at
           | 1.53x input energy is not just breakeven, but net gain. This
           | is the first time ever we've gotten net gain, in any fusion
           | device. A lot of people in gov leadership thought fusion was
           | impossible, the fact they can said they did it, despite 1980s
           | era technology and a shoestring budget for decades, really
           | says something. ICF is just one fusion technology, and
           | probably not the best one, but fusion in general will
           | probably see a massive budget increase worldwide now that
           | it's been proven it can be done.
           | 
           | I fully expect a working fusion plant of some kind by 2030,
           | assuming funding increases. Once we get them commercialized;
           | coal, wind, solar and other power production will be obsolete
           | for the most part. We can also use fusion heat to separate
           | waste into it's base elements (you can recycle anything!),
           | and help make any process needing a lot of thermal or
           | electrical energy more efficient.
        
             | pauljurczak wrote:
             | > I fully expect a working fusion plant of some kind by
             | 2030
             | 
             | Right. The first law of fusion physics: working fusion
             | power generation in 10 years. It has been proven true for
             | the last 7 decades. Rock solid.
        
               | bratbag wrote:
               | The joke used to be fusion was always 30 years away. Then
               | the joke was it was always 20 years away. Now the joke is
               | it's always 10 years away.
               | 
               | People paying attention over this time have noticed it
               | getting closer as we improve our capabilities.
               | 
               | The next iteration of the joke will be 'fusion was always
               | inevitable'
        
               | Valakas_ wrote:
               | At some point, people will still be predicting fusion in
               | the next 10 years, and then it will happen in the next.
        
             | bearmode wrote:
             | Regular fission plants take 5+ years to construct. So in
             | the next 2-3 years you're expecting this technology to
             | become mature enough to roll out and hook up to the power
             | grid?
        
             | arbitrandomuser wrote:
        
             | ag315 wrote:
             | By 2030? Lol. Lmao, even. 2050 if we're lucky--we're still
             | not even close to developing a reactor that can produce
             | meaningful amounts of power for a sustained period. It'll
             | take decades more to get to that point, and once all the
             | technical limitations have been crossed and we figure out
             | how to get enough tritium, the actual hard work begins of
             | getting it online and integrated with our current system.
             | Fusion is distant future technology.
        
           | postingawayonhn wrote:
           | As I understand it that's largely because some of their
           | equipment is outdated or not optimised. Building a new
           | facility from scratch would result in a much lower power
           | consumption from the grid.
        
             | rtpg wrote:
             | given how long it takes to build these places, I feel like
             | the number of iteration cycles is an important metric,
             | especially when other options are not standing still.
             | 
             | I do understand that with more focus things can happen
             | faster but you can really only pour so much concrete per
             | day. Hopeful that we can figure out "leaner" ways to get
             | this done.
             | 
             | I would love to see progress on this stuff, just don't like
             | the idea of betting on successive megaprojects in the age
             | of "a website is hard".
        
               | prpl wrote:
               | Iteration is often overlapping. Day 2 of operations is
               | usually planning the next generation (for a given
               | project)
               | 
               | Adding more funding will probably see more parallel
               | projects as well, especially at major institutions
        
           | zbobet2012 wrote:
           | A quick peruse through this wikipedia article will tell you
           | what still needs done, and what this means:
           | 
           | https://en.wikipedia.org/wiki/Laser_Inertial_Fusion_Energy
           | 
           | Give it a read. Intertial confinement fusion with a Q > 1 may
           | very well point the way towards a realistic powerplant.
           | Fusion is at a point it deserves investment. The NIF cost
           | about the same as a single b-2 bomber.
        
             | njarboe wrote:
             | Total annual US public research into fusion that is not
             | ITER or this project (which does not come from the fusion
             | pot. As others have said this project was built for weapons
             | research) is about $300 million per year[1]. We, as a
             | country, do not give a rats ass about having fusion as a
             | power source. VC funding recently (for the first time)
             | supported many fusion startup ideas at or above the $300
             | million level. Too bad ZIRP is over and private funding is
             | now likely to dry up. The recent private funding in fusion
             | was really amazing. Many new ideas and methods are being
             | tried. This is what fusion research needed. Not spending
             | billions on magnets and cement in France that is ITER.
             | Hopefully some of them have a long enough runway to get
             | promising work done and get follow-up funding.
             | 
             | [1]http://large.stanford.edu/courses/2021/ph241/margraf1/im
             | ages...
        
               | moloch-hai wrote:
               | We may be certain, anyway, that all the startups will
               | spend _all_ the money they get. There will be no power
               | generated. The investors will not get any of their money
               | back.
               | 
               | That would be fine, except some of the investors are
               | pension funds.
        
           | hyperbovine wrote:
           | Explains why the experiment took place at 1am.
        
           | hackbinary wrote:
           | 300 MJ is about 83 KWh.
           | 
           | In the UK is 1 KWh is PS0.34
           | 
           | So, this costs PS28 in electricity to run this experiment.
           | The experiment is a momentary thing.
           | 
           | Clearly there is now some work to, but now this is becoming
           | an engineering problem of how to extend, sustain, and scale
           | this process.
        
             | tuatoru wrote:
             | To have a hope of supplying grid power, they need to scale
             | up the energy gain by four orders of magnitude and reactor
             | run time by 12 orders of magnitude.
             | 
             | Those are just two of the engineering problems. It'll be a
             | while, and I doubt it will ever compete with solar, wind,
             | and storage.
        
               | eru wrote:
               | > [...], and I doubt it will ever compete with solar,
               | wind, and storage.
               | 
               | Maybe not on earth, but there are applications in deep
               | space.
        
               | rbanffy wrote:
               | > Maybe not on earth, but there are applications in deep
               | space.
               | 
               | Depends on how long the interstellar craft is supposed to
               | travel. If it's under 100 years, fission should be able
               | to do the trick of keeping the craft warm and the lights
               | on for the sealed ecosystem to function during the
               | decades of coasting between stars.
               | 
               | Fusion rockets would be more convenient than fission ones
               | because you can store the hydrogen you need in the form
               | of water and water also acts as a great radiation shield
               | while in deep space. Then, to brake, you use your
               | radiation shield as reaction mass for fission or fusion
               | rockets.
               | 
               | If we are talking about much more than that, fusion is
               | probably a better answer as fission fuel will half-life
               | itself into paperweights over a grand transgalactic tour.
        
               | danw1979 wrote:
               | This is exactly why we need to keep plugging away at
               | fusion - one day we'll need it in space. It doesn't have
               | to be cheap, it just has to work.
        
               | eru wrote:
               | Of course, whether that's a good investment of resources
               | right now is another question.
               | 
               | Even if we had no other goal than becoming an
               | intergalactic species as soon as possible, we might still
               | benefit from working on other things first.
        
               | bratbag wrote:
               | You are operating under the rather naive assumption that
               | the people and resources used in fusion research are
               | fungible with the people and resources used in other
               | things.
               | 
               | When you have a bunch of people who know how to build
               | nuclear bombs sitting around with nothing to do, you damn
               | well keep them busy before another country finds them a
               | job.
        
             | doctorwho42 wrote:
             | Having worked in the field for 6 years, the estimated cost
             | per shot at NIF is roughly $1MM. The estimated cost for a
             | day of shots at OMEGA is $250k-$300k.
             | 
             | The cost per target varies a lot due to the precise
             | manufacturing tolerances and the methods to get them. For
             | example, the sphere with the fuel in it is made by dropping
             | liquid glass from a drop tower. And then metrology is done
             | on hundreds and hundreds of glass spheres.
             | 
             | So though the electricity might cost that, we are talking
             | about a building in which just the lasers and their optical
             | paths take up 3 foot ball fields of advanced warehouse
             | space. And the target chamber is at ultra high vacuum,
             | which is 10 meters in diameter. There are also countless
             | diagnostics, computers, and other electronics, the lights
             | for all the facility, and the number of people required to
             | run it so this delicate experiment goes off without a
             | hitch.
             | 
             | Honestly, it's almost not worth talking about as a power
             | source anytime soon. Even if Q > 2 on NIF there are
             | countless engineering problems that would have to be
             | overcome (and haven't really been thought too hard on in
             | the ICF field) to get a power reactor out of this tech.
             | 
             | My two cents, look towards MIT and CFS for news on their
             | SPARC tokamak and plans for ARC tokamak. Based on some data
             | I have seen, SPARC should hit Q>1 pretty easily. With some
             | estimates of reaching Q> 3 to 9. And before you scoff at
             | it, this reactor design is using magnetic tech that has
             | proven it can withstand and produce a 20T magnetic field!
             | In MCF, field strength and heating are the two key metrics.
             | To put this into perspective, the massive tokamak being
             | built in Europe has a MAX possible field strength of 13T,
             | assuming it's run to the edge of it's theoretical design
             | limitations. The SPARC one hasn't even been run to it's
             | design limitations, most likely due to the mechanical
             | stresses a 20T field produces in a 3-4 meter D coil.
        
             | [deleted]
        
             | [deleted]
        
             | moloch-hai wrote:
             | Plus $10M for the target bead.
        
               | philipkglass wrote:
               | Where did you see this estimate for hohlraum cost?
               | 
               | The NIF fired 368 shots in 2021:
               | 
               | https://lasers.llnl.gov/for-users/nif-target-shot-metrics
               | 
               | At $10 million per target that would cost $3.7 billion.
               | The annual LLNL budget (which includes NIF) is only $2.8
               | billion:
               | 
               | https://www.llnl.gov/doing-business/economic-impact
               | 
               | As of 2004, the targets were reported to cost $2500 each:
               | 
               | https://www.osti.gov/servlets/purl/828518
        
               | moloch-hai wrote:
               | Got it from a comment on here.
               | 
               | The 2004 targets didn't work. Neither did the 368 shots
               | in 2021. Maybe ones that work cost more?
               | 
               | Even $2500 for 1 kWh is rather steep.
        
         | makestuff wrote:
         | > It's nice to see this milestone recognized, even if the
         | funding it still rather small.
         | 
         | Just wait until the DoD figures out they can use this for some
         | military application and it will get 100x funding overnight.
        
           | davedx wrote:
           | We've had thermonuclear weapons (h-bombs) for a long time
           | already.
           | 
           | Harnessing the energy in a _controlled and sustainable
           | fashion_ is what 's hard.
        
             | TeeMassive wrote:
             | H-bombs use the hydrogen to produce more neutrons which
             | boosts the fission process. It still is a fission bomb.
        
               | Analog24 wrote:
               | You have it backwards. The fission component is just the
               | "trigger" for the fusion element, which produces the vast
               | majority of the energy release.
        
               | TeeMassive wrote:
               | Half of the energy comes from the fissile "spark plug"
               | that's inside the fusion material. Less than half of the
               | energy comes from fusion.
               | 
               | It still very much is a fission weapon.
        
               | yk wrote:
               | No, you can have a fusion booster, like in the "Sloika"
               | [0] design, but for a Teller-Ulam design, that is a
               | H-bomb, you use a nuclear primer to ignite a fusion
               | reaction and by far the most energy comes from the fusion
               | part. [1]
               | 
               | [0] https://www.atomicarchive.com/history/hydrogen-
               | bomb/page-11....
               | 
               | [1] https://nuclearweaponarchive.org/Library/Teller.html
        
               | zbobet2012 wrote:
               | You are correct that in a Teller-Ulam design most of the
               | energy can come from fusion, but as a note it's generally
               | a fission-fusion-fission design in "modern" deployments
               | with about 50% of the energy coming from fusion.
               | 
               | https://en.wikipedia.org/wiki/Thermonuclear_weapon
               | 
               | Only very large bombs, such as the Tsar Bomba (97% from
               | fusion) ever where primarily fusion, and those are not in
               | modern arsenals.
        
               | TeeMassive wrote:
               | Half of the energy comes from the fissile "spark plug"
               | that's inside the fusion material. Less than half of the
               | energy comes from fusion.
               | 
               | It still very much is a fission weapon.
        
               | davedx wrote:
               | Nope...
               | 
               | "thermonuclear bomb, also called hydrogen bomb, or
               | H-bomb, weapon whose enormous explosive power results
               | from an uncontrolled self-sustaining chain reaction in
               | which isotopes of hydrogen combine under extremely high
               | temperatures to form helium in a process known as nuclear
               | fusion."
        
               | jboy55 wrote:
               | Yes, but if you get into the details... The second stage
               | of a bomb is the fusion in which a cylinder of hydrogen
               | and/or lithium is encased by U-238. The primary stage, a
               | trinity-like a-bomb, forces the cylinder to compress by
               | its x-rays. The fusion reaction creates a bunch of
               | energy, but more importantly a huge amount of neutrons.
               | These neutrons cause the u-238 to undergo fission, which
               | is responsible for a majority of the energy and pretty
               | much all of the fallout.
        
               | TeeMassive wrote:
               | The fissile "spark plug" inside the fusion material is
               | responsible for the majority of the energy...
        
           | p_j_w wrote:
           | This is already used for nuclear weapons research, which is
           | why it's under Dept. of Energy.
        
             | davrosthedalek wrote:
             | Not really. I mean, yes, nuclear weapons are a thing, but
             | Dept. of Energy supports many many directions not related
             | to nuclear weapons. Physics research is mostly funded by
             | DOE Office of Science or the National Science Foundation.
        
               | saboot wrote:
               | It's an explicit goal of the NIF to better understand the
               | physics of fusion for weapons research. Not the main one
               | but it's pretty important!
        
               | davrosthedalek wrote:
               | My point was: NIF would be funded via DOE whether or not
               | it's relevant for weapon research. Sorry for not have
               | been clearer.
        
               | zizee wrote:
               | I'm no expert, but I think you have it backwards. My
               | understanding is NIF raison d'etre is weapons research,
               | with a power generation being a secondary concern. It got
               | funded because of weapons research regardless of whether
               | it was relevant to fusion power generation.
               | 
               | It may surprise people, but the DOE is the government
               | body that is responsible for nuclear weapons research in
               | the US.
        
               | saboot wrote:
               | If it was already decided to be funded, yes it would have
               | been under DoE. Though I believe the weapons aspect had a
               | very major contribution in deciding for it to be funded
               | at all. It was proposed shortly after the nuclear testing
               | ban and has been a big part in fulfilling that area.
               | 
               | I'm not trying to correct you, but adding context for the
               | weapons aspect.
        
               | davrosthedalek wrote:
               | Yes, you are right, the funding decision was probably
               | influenced by the weapons research.
        
             | kortilla wrote:
             | That doesn't follow. The DOE covers a bunch of energy
             | research that has no relationship to nuclear weapons (e.g.
             | solar).
        
           | lambdatronics wrote:
           | Uhhh... it's definitely being used for "stockpile
           | stewardship." The fusion crowd went splitsies with the
           | weapons folks to get this funded in the first place.
        
           | jameshart wrote:
           | Cheap and abundant energy has a multitude of military
           | applications.
           | 
           | Peaceful ones too, probably.
        
           | saboot wrote:
           | The appropriate analogy for this technology would be that it
           | may be possible to initiate a thermonuclear weapon without
           | relying on fission at all. Currently we use a fission nuclear
           | bomb just to generate the temperature and pressure needed to
           | start the fusion reaction, same as the one on today's
           | announcement.
           | 
           | So far it hasn't proven to be viable, but time will tell.
        
         | tgflynn wrote:
         | I wonder if it might be possible to gain not percentages but
         | orders of magnitude more or less just by making the targets
         | bigger. Is it conceivable that the same basic approach and a
         | comparable amount of input energy could be used to ignite a 100
         | MJ or even 1 GJ target ? Of course that would present some
         | containment challenges but perhaps not insurmountable ones.
         | 
         | I'm also a bit concerned that this type of research may
         | encounter national security related obstacles. Obviously a pure
         | fusion bomb would be a game changer for nuclear
         | (non-)proliferation.
        
           | jocaal wrote:
           | I don't think a pure fusion bomb will have any form of
           | advantage compared to the current hydro-bombs. They wouldn't
           | produce more energy, but will need more gear to reach
           | ignition.
        
             | tgflynn wrote:
             | The advantage would be that you wouldn't need tightly
             | controlled and hard to make materials like U-235 or Pu to
             | make one.
             | 
             | I'm not in any way saying that using lasers would be a
             | plausible route to such a weapon, since the NIF facility is
             | huge, but if it turns out that the research needs to focus
             | on how to get more output per shot, which I think it
             | inevitably would since a typical conventional or nuclear
             | power plant generates on the order of 1 GW thermal power
             | (To match that with a 1 Hz repetition rate, likely a
             | stretch for a MJ class laser, you would need to generate 1
             | GJ per shot, comparable to the energy in a ton of TNT.), it
             | would probably be touching on areas that are highly
             | classified.
        
               | yamtaddle wrote:
               | Shiiiit... here I was thinking how cool it would be if
               | they could miniaturize this, having somehow forgotten
               | that my pet solution to the Fermi paradox is that a nigh-
               | inevitable wrung on the ladder to interstellar presence
               | involves discovering One Weird Trick to release a whole
               | bunch of energy pretty easily, even on a DIY basis.
               | Instant end of civilization. Even ant-like societies
               | might have mutated members who'd go rogue and misuse the
               | tech, and it wouldn't take many to ruin everything.
               | 
               | Basically it's a twist on the ice-9 solution to the
               | paradox.
        
               | sterlind wrote:
               | any sufficiently speedy spacecraft makes for a deadly
               | kinetic kill vehicle, unfortunately.
        
               | jboy55 wrote:
               | One use for such a 'laser initiated fusion' is the LLNL
               | (Teller) proposed X-Ray laser satellite from the Star
               | Wars program in the 80s. The proposed solution then was
               | to use the X-rays from an exploding bomb at the heart of
               | a satellite and amplify and focus them through a 'lasing'
               | material. It turns out they never found a lasing material
               | that would work, and it would be fairly easy to confuse
               | defeat it, so the project died. What also killed it was
               | the end of the testing program.
        
             | LarryMullins wrote:
             | A pure fusion bomb would produce less (not zero) fallout.
             | Neutron activation would still produce some fallout, but
             | you wouldn't have the fission byproducts like caesium-137,
             | iodine-129 or strontium-90.
             | 
             | This is probably a bad thing; politicians might decide the
             | bombs are clean enough to use.
        
               | sterlind wrote:
               | even without actual radioactivity, pure fusion bombs
               | would still be politically radioactive. look at the
               | fallout (so to speak!) from the Hafnium controversy. they
               | nixed all the research and stopped looking, after
               | realizing that nuclear isomers would do little for energy
               | storage (due to emitting energy as gamma radiation) but
               | lots for bypassing restrictions on fissile materials.
        
               | LarryMullins wrote:
               | To be clear, pure fusion bombs would still emit massive
               | amounts of radiation. Gamma rays, x-rays, thermal
               | radiation, all off that EM radiation would be emitted
               | just like a regular fission bomb. Neutron radiation too.
               | You'd have less (not zero) contamination of the earth
               | itself afterwards, but everybody in the area would still
               | be very badly irradiated.
               | 
               | I don't know enough about the Hafnium controversy to
               | comment on it.
        
           | spullara wrote:
           | I mean almost all of the power in a nuclear bomb comes from
           | fusion. The fission part of it is just like the detonator for
           | the real explosion.
        
             | dgacmu wrote:
             | This is actually backwards. Fusion weapons are
             | substantially higher yield because they result in more
             | fission, partly by preventing the fission primary from
             | blowing itself up before it has finished.
             | 
             | Wikipedia: "Fast fission of the tamper and radiation case
             | is the main contribution to the total yield and is the
             | dominant process that produces radioactive fission product
             | fallout."
             | 
             | https://en.m.wikipedia.org/wiki/Thermonuclear_weapon
        
               | jboy55 wrote:
               | Most of the fission energy in an H-bomb comes from the
               | massive amounts of neutrons created by the fusion bomb
               | initiating a fission reaction in the U-238 tamper of the
               | secondary. The primary is used for its X-Rays, which
               | cause the incredible pressures within the secondary by
               | ablating the surface of the cylinder. When you look at
               | this experiment and see it uses x-rays to ablate case
               | containing the hydrogen, causing an implosion, the
               | purpose of the experiment is clear.
        
               | Retric wrote:
               | It varies quite a bit by design, apparently the USSR's
               | initial design was only 15-20% fusion while US designs
               | where closer to 50% which is still apparently the most
               | efficient option in terms of warhead size.
               | 
               | However it's possible to have higher fusion ratios at the
               | expense of a larger device for the same yield. Most
               | notably in the case of the Tsar Bomba's which reduced the
               | contribution of fission and too massively reduce the
               | amount of fallout produced.
        
             | phasetransition wrote:
             | Almost all nuclear weapons rely heavily on fission of the
             | tamper for yield.
             | 
             | Suggest "Ripple: An Investigation of the World's Most
             | Advanced High-Yield Thermonuclear Weapon Design" from the
             | Journal of Cold War studies to read about a predominantly
             | fusion device family.
        
               | AlanSE wrote:
               | This seems to say to me that D-T reactions produce
               | neutrons, and that the kinetic energy of the neutrons is
               | smaller than what you get by hitting U with that neutron.
               | You already have the energy from the neutron (which will
               | land somewhere in the system eventually), and you might
               | as well get a multiplier by putting a blanket of U-238 in
               | front of it.
               | 
               | That could be carbon-copied to a fusion power plant, and
               | indeed, there are many proposals of hybrid fusion-fission
               | plants in the literature that only require Q values
               | marginally greater than 1. But if you go that route, you
               | have radiation just like a fission plant, and one starts
               | to question why you don't just build a fission plant
               | (indeed, why don't we?).
               | 
               | My personal pet theory of the future is that, one day,
               | we'll progress so far in fusion research that we get
               | economic energy. But at the same time, the line blurs
               | between both fission and weapons technology, so people
               | are unhappy with the result. This doesn't feel
               | particularly contrarian but no one ever seems to bring it
               | up.
        
               | moloch-hai wrote:
               | Since you asked: We don't build fission plants because
               | they cost more than every other energy source. Fusion
               | plants, if they could ever be made to work at all, would
               | cost a lot more. So, there won't be any.
        
           | lambdatronics wrote:
           | The bigger the target, the more energy is needed to compress
           | it. So it would require more laser energy to get to 100 MJ or
           | 1 GJ, I think. But maybe only a few times more powerful.
           | (Pity they didn't build in some head room!)
        
             | tgflynn wrote:
             | The question is whether once ignition is achieved there
             | could be a way to design the target/geometry in such a way
             | that the fusion reaction becomes self-sustaining/self-
             | propagating.
             | 
             | The history of thermonuclear weapons leads me to think that
             | the answer may be yes. There does not seem to be any real
             | upper limit to how large a thermonuclear weapon can be
             | made. In the 50's and/or 60's there were proposals to build
             | GT devices. I don't think the fission trigger for such a
             | weapon could have scaled by nearly as much.
             | 
             | So by analogy if a relatively small fission trigger can
             | cause a fusion explosion that is many orders of magnitudes
             | larger maybe one or more tiny laser induced fusion
             | reactions could be used to trigger a much larger one.
             | 
             | If that were the case the efficiency of the laser trigger
             | would be of little importance.
        
           | metal_am wrote:
           | This particular research is literally built off of weapons
           | research (National Ignition Facility).
        
             | tgflynn wrote:
             | Yes but, as far as I know, research into achieving laser
             | induced fusion hasn't itself run into many classification
             | hurdles. I suspect that may not be the case with the
             | scaling phase.
        
               | jboy55 wrote:
               | It is interesting that there hasn't been many
               | classification hurdles on something that is pretty
               | explicitly weapons research. My guess is that they
               | achieved high Q values a long time ago in classified
               | research using mechanisms that would give away some
               | secrets.
        
               | tgflynn wrote:
               | I think it's mainly because using a laser the size of a
               | football stadium was never seen as a practical way to
               | make a bomb.
        
               | jboy55 wrote:
               | Well, its not so much in making the bomb, but the
               | particular ways of focusing the X-Rays and particular
               | efficiencies in creating the tamper for the most velocity
               | and thus most compression in the secondary.
               | 
               | The key thing here is the Lasers aren't doing the
               | immediate compression, the lasers are simulating X-Ray
               | radiation which then is ablating the casing around the
               | tritium. Figuring out how to create and amplify a x-ray
               | pulse was a major sticking point in the Star Wars
               | program.
        
               | kevin_thibedeau wrote:
               | It's intended to confirm computer simulations. It doesn't
               | have to be viable for the end article.
        
         | pfdietz wrote:
         | The Q needs to be something like 500 to 1000, not because of
         | energy breakeven, but to produce enough energy that the shot is
         | financially positive. The amount of fusion energy produced in
         | this shot is worth a penny or two.
         | 
         | (And even then, it's dubious a laser fusion scheme will be
         | competitive with other energy sources.)
        
           | echelon wrote:
           | It will get there. It's just a matter of time and resources.
           | 
           | The destination will be a milestone for humanity, so we
           | should not give up.
        
             | pfdietz wrote:
             | Why should I agree with this article of faith? The
             | obstacles appear quite grave to me. Moreover, even reaching
             | that Q doesn't mean we're there. That's a necessary, not
             | sufficient, condition.
             | 
             | A large, complex machine that explodes the equivalent of
             | 500 lb. bombs to generate heat to drive a turbine sounds
             | like an engineering nightmare.
        
               | m4rtink wrote:
               | I wonder how much energy each stroke in the largest
               | diesel ship engines has when compared to the energy
               | released by individual bombs/high explosives.
        
               | Quarrel wrote:
               | While I'm sure that you're correct, the obstacles are
               | large and there is a lot of overcome still, I can't help
               | but think of James Watt & (my ancestor) Richard
               | Trevithick - the inventor/pioneer of the compact steam
               | engine.
               | 
               | Watt went around telling everyone that Trevithick and his
               | compact (ie high pressure) steam engines were too
               | dangerous and would never work.
               | 
               | Yes, some exploded. But then we got steam trains and even
               | today almost all power generation on the planet is high
               | pressure steam-electric power plants.
        
               | aaroninsf wrote:
               | An answer matched in tenor and tone to the question, but
               | nonetheless entirely serious,
               | 
               | is that because while the obstacles are grave, the
               | consequences of failing to overcome them are much graver
               | still,
               | 
               | and to the best of our collective knowledge,
               | 
               | industrial scale fusion would be the least bad answer to
               | our energy demands for the next epoch.
               | 
               | That is true but also does not obviate the need for other
               | parallel efforts and other technologies whose challenges
               | are also very grave, e.g. the need for very near term
               | very large scale carbon sequestration, for a modern
               | electrical grid with deep redundancy and resilience, the
               | need for effective safe scalable stores for energy from
               | whatever source, etc.
        
               | pfdietz wrote:
               | > the consequences of failing to overcome them are much
               | graver still,
               | 
               | Why is that? Fusion is not needed, although if it turned
               | out to be cheap that would be nice.
        
               | azinman2 wrote:
               | Because sustainable positive energy out has never been
               | achieved before in 60 years of research. This is
               | gigantic. It's potential to decarbonize the world is
               | massive, and now it became a whole lot less theoretical.
               | 
               | It's an incredible milestone, not a solved problem.
        
               | pfdietz wrote:
               | That's a circular argument. It's big because the people
               | doing it call it big. Why should I, an outsider, care
               | about their internal goals, their egoes, or their status
               | in their field? What does it do or imply for me?
        
               | lkbm wrote:
               | > It's big because the people doing it call it big.
               | 
               | How does "[It's big b]ecause sustainable positive energy
               | out has never been achieved before in 60 years of
               | research" translate to "because we say it's big" in your
               | head?
               | 
               | You might not consider it big, but a specific reason was
               | provided and it had zero similarity to your rephrasing.
        
               | azinman2 wrote:
               | To achieve fusion for power production, you need more
               | output than input. For 60+ years this hasn't been
               | achieved in a replicated fashion. Now it has, and it's
               | 50% more power rather than 0.1% more power as was
               | sometimes shown for 2 nanoseconds before. So now we know
               | fusion for power is possible. If it can be scaled
               | successfully (now likely not an if anymore, but a
               | function of time), then we have the ability to have clean
               | and safe energy 24/7. That would help mitigate the worst
               | of climate change, and if cheap, turbocharge the entire
               | economy.
               | 
               | What's the circle or not big milestone here?
        
               | jboy55 wrote:
               | The issue is, we've been able to get more energy out of a
               | fusion reaction than put in for 60-70 years now. The
               | H-Bomb is very good at doing that. You will say, yeah,
               | but an H-Bomb is a one time use thing, and it has a habit
               | of destroying everything. If you look into how the second
               | stage of an hbomb is speculated to work, its pretty much
               | identical to this experiment, that is by design, not by
               | accident.
               | 
               | From https://www.nature.com/articles/d41586-022-04440-7
               | 
               | Herrmann acknowledges as much, saying that there are many
               | steps on the path to laser fusion energy. "NIF was not
               | designed to be efficient," he says. "It was designed to
               | be the biggest laser we could possibly build to give us
               | the data we need for the [nuclear] stockpile research
               | programme."
        
               | azinman2 wrote:
               | *contained fusion
        
               | pfdietz wrote:
               | I'm asking why this somewhat arbitrary line being crossed
               | is something I should care about. It doesn't imply fusion
               | will reach a state of practical application. Why is this
               | more exciting that achieving a ratio of .1, or .5, or 2,
               | or 10? It seems entirely arbirary to me, and smells of an
               | argument that somehow this has made the end goal
               | significantly more attainable.
        
               | azinman2 wrote:
               | Because until now contained ignition has never produced
               | anything meaningful. We've had failed experiment after
               | failed experiment. Now we finally have an experiment with
               | a meaningful more amount of energy out than in.
               | 
               | Is this the right approach? Who knows. There are many
               | fusion designs in the works, and those may ultimately be
               | the right call. Or some yet-to-be-created design. That's
               | even probable. The NIF is for simulating nuclear weapons,
               | not creating energy. None of that takes away from this
               | breakthrough - we've never had meaningfully more output
               | than input on a repeatable basis. It's proof that
               | contained fusion for energy isn't just hypothetical,
               | which will also mean funding & interest will generally
               | increase from this point on.
               | 
               | I think you're setting too high a bar. It's like saying
               | no milestone should be celebrated until we have a working
               | metropolitan-size plant running that's cheaper than
               | anything else. Punch cards in the 1950s are insignificant
               | compared to modern SSDs, yet they were an important step
               | even though we don't use anything like it now.
               | Breakthroughs are breakthroughs.
        
               | floxy wrote:
               | >It seems entirely arbitrary to me
               | 
               | I agree that the original press release flubbed the
               | explanation. Here's how I think they should have
               | presented it instead:
               | 
               | https://news.ycombinator.com/item?id=33971377#33977940
        
               | floxy wrote:
               | >why this somewhat arbitrary line being crossed is
               | something I should care about.
               | 
               | That is something personal and unique to each individual.
               | In 1903 when the Wright brothers flew a heavier-than-air
               | machine for 59 seconds, 99.99999% of the people on the
               | planet wouldn't have cared. The airplanes you've flown on
               | are vastly far removed from that original one. Same story
               | for the point contact transistor in 1947. None of that
               | solid state physics is used for modern transistors. Some
               | people like to be early adopters for new ideas and
               | things. Some don't. And that is OK.
        
               | TheCoelacanth wrote:
               | It's a common joke that fusion power is always 50 years
               | away. With this milestone, is it finally less than 50
               | years away?
        
               | ClumsyPilot wrote:
               | > A large, complex machine that explodes the equivalent
               | of 500 lb. bombs to generate heat to drive a turbine
               | sounds like an engineering nightmare.
               | 
               | And using actual bombs and explosives to dig kilometers
               | down and mine coal is not an engineering nightmare? Dying
               | of gas in the mines, fires on oil wells, oil spills,
               | these things are 'engineering simple'?
        
               | pfdietz wrote:
               | We don't place precision optics in those blast zones. We
               | don't put structures there that are repeatedly exposed to
               | blast. Over the life of a inertial DT fusion reactor
               | there will be about a BILLION such explosions in the
               | reactor core.
        
             | pelorat wrote:
             | It will get there, but it won't be from NIF or via any
             | technology developed for this experiment. What they are
             | doing is not viable for a rector, won't ever be viable for
             | a reactor, and won't even be considered a starting point
             | for any future rector.
             | 
             | It's a fusion plasma research experiment. It's not a
             | program that is being run with the goal of creating a
             | usable fusion energy power plant.
        
           | YetAnotherNick wrote:
           | > The Q needs to be something like 500 to 1000
           | 
           | Is there any calculation to this? What's the cost of shot? Is
           | there any limetime limit of the laser?
        
           | VLM wrote:
           | Its worth pointing out that per unit energy a lot of money is
           | made making economically unviable cargo ship power, submarine
           | and other military naval power, space ship power sources,
           | diesel-electric locomotives ...
           | 
           | True if you want to replace base load of a civilization size
           | network it needs to be economically viable, but we generate
           | "a lot" of power at higher than market minima. Ironically,
           | "good batteries" are the natural enemy of fusion research.
           | 
           | One fun thing about laser fusion is it theoretically can
           | scale down very low and has a trivial "off" switch making it
           | a good resource for engineering tokamak reactor materials or
           | sensors or similar tasks.
           | 
           | The inner lining of a production fusion reactor is hard to
           | make, so a laser facility would be ideal for research. Which
           | is why we have one...
        
             | pfdietz wrote:
             | DT fusion reactors would be terrible for mobile
             | applications, since there are so much larger than fission
             | reactors of the same capacity. In space or mass constrained
             | applications they would be ruinously inferior to fission.
        
           | hackernewds wrote:
           | Offset the financial viability with the cost of freedom from
           | energy reliance and the need (more like craving) for military
           | interventions
        
             | pfdietz wrote:
             | That would be a valid argument if the only alternative to
             | fusion was petroleum.
        
               | orthecreedence wrote:
               | I'm confused by this. Does the US have the productive
               | forces and resources to replace petrolium with solar
               | panels (and the required energy storage)? Does it have
               | the nuclear fuel to replace petrolium with fission
               | reactors?
               | 
               | What alternatives to petrolium does the US have that it
               | does not rely on others for?
        
               | pfdietz wrote:
               | What scheme do you imagine that fusion could be used to
               | replace petroleum that would not also work when powered
               | by solar? Production of synfuels using hydrogen, for
               | example, would also deal with solar's intermittency,
               | leaving the energy sources to compete on the basis of
               | levelized cost. The levelized cost of solar has become
               | quite low, and it's very difficult to see how any fusion
               | scheme, and DT fusion in particular, will ever compete.
        
               | orthecreedence wrote:
               | I specifically asked about the _production_ of solar
               | panels. Are you assuming that we already have all the
               | panels we need to replace petrolium sitting in a
               | warehouse? What good is solar in an energy independence
               | plan if we can 't build our own panels?
        
               | pfdietz wrote:
               | What? Production of solar panels is just a matter of
               | building and running more factories. There's no
               | significant limit to this.
        
               | Firmwarrior wrote:
               | Nuclear fuel actually isn't that expensive or rare
               | 
               | Those crazy sci-fi stories from the 30s and 50s where
               | everyone used nuclear power (and it was so cheap they
               | didn't bother to meter it) were all completely accurate
               | from a non-political viewpoint
        
               | orthecreedence wrote:
               | Oh, interesting. I read/heard a few places that most fuel
               | used for fission was controlled by a few countries. I was
               | unaware it was abundant.
        
               | vel0city wrote:
               | The stuff is kind of all over the place, but it's not
               | high purity. The engineering to refine the material is
               | highly controlled.
        
               | mywittyname wrote:
               | Exactly. Beyond power generation, humanity still uses
               | petroleum products in their chemical industry. Which is
               | why the shutoff of Russian natural gas hurts Germany much
               | more than other countries, they now have a starving
               | chemical sector.
        
             | ajuc wrote:
             | Solar panels (+ synthetic fossil fuel generation if you
             | need unlimited energy storage) would be orders of magnitude
             | cheaper way to achieve that.
        
             | baq wrote:
             | Military interventions to blow up other people's under
             | construction fusion reactors will still be a thing, worry
             | not
        
             | colechristensen wrote:
             | Foreign energy reliance is finished and has been for some
             | time. North America can produce more petroleum energy than
             | it uses. In both 2020 and 2021 the US was a net petroleum
             | exporter.
        
           | floxy wrote:
           | >The Q needs to be something like 500 to 1000
           | 
           | Why wouldn't a final Q of 50 be economically viable? Interest
           | on capital costs? Other?
        
             | Tuna-Fish wrote:
             | Inertial confinement fusion requires fairly expensive
             | targets to collapse. To make it economically viable they
             | have to produce a lot more energy per target destroyed.
        
               | londons_explore wrote:
               | > fairly expensive targets
               | 
               | The targets are only expensive because they aren't
               | produced at scale yet.
               | 
               | They are the exact kind of thing a machine could churn
               | millions of per day out, and then use them at the same
               | rate.
               | 
               | Even if the targets were made of expensive materials (eg.
               | platinum), most of that platinum could later be recovered
               | from the reactor wall, so it still wouldn't be very
               | expensive.
        
               | hutzlibu wrote:
               | "most of that platinum could later be recovered from the
               | reactor wall, so it still wouldn't be very expensive. "
               | 
               | And recovering comes for free?
               | 
               | Every step costs energy (or money).
               | 
               | There is no working design yet. It is waay too early to
               | make any predictions about how scaling could reduce
               | costs. Scaling can even increase costs, if it depletes
               | limited resources like tritium.
        
             | pfdietz wrote:
             | Capital cost, cost of individual targets.
        
               | andruc wrote:
               | If you've done the math to determine the threshold, you
               | may as well show it already
        
               | pfdietz wrote:
               | I'm repeating what I've heard. Personally, I suspect even
               | that wouldn't reach the goal of being competitive.
        
           | ClumsyPilot wrote:
           | Q is irrelevant, you need throughput. If your Q is one
           | million, but you are processing one tiny capsule per second,
           | you are producing too little money to pay for the facility.
           | 
           | If you can process a tanker worth of hydrogen per second, Q
           | can be just above break even and you will still make money.
        
             | lkbm wrote:
             | Irrelevant? Seems like Q is one of two factors in that
             | calculation. If the throughput is tiny, you're useless, but
             | if your Q is too small, the same is true.
             | 
             | The higher the Q, the lower throughput needed for
             | feasibility.
        
         | sillysaurusx wrote:
         | This tweet claims that 500MJ of energy was required:
         | https://twitter.com/latzenpratz/status/1602686252486217728
         | 
         | > "had to put 500 megajoules of energy into the lasers to then
         | send 1.8 megajoules to the target - so even though they got 2.5
         | megajoules out, that's still far less than the energy they
         | originally needed for the lasers," says Tony Roulstone of the
         | University of Cambridge.
         | 
         | But it's good to finally see progress. Very few technologies
         | can transform the world the way a practical fusion reactor
         | could.
        
           | Robotbeat wrote:
           | That's only because they're using old school flash pumped
           | lasers, not the new solid state lasers you'd use today if you
           | wanted to make a power plant demo.
        
             | BeetleB wrote:
             | Can solid state lasers produce the high energy needed here?
        
               | Robotbeat wrote:
               | Yes. https://en.wikipedia.org/wiki/Laser_Inertial_Fusion_
               | Energy#M...
        
               | px43 wrote:
               | I'm not really seeing any convincing numbers there.
               | Mercury lasers seem to only be 10% efficient. I get that
               | this is better than the lasers that were just used at
               | NIF, but that still seems pretty far from useful.
        
               | Robotbeat wrote:
               | It's useful enough to produce significant net energy if
               | they continue with the gain scaling that ignition allows.
        
             | sillysaurusx wrote:
             | It just seems a little strange to take credit for a
             | milestone when the milestone everyone cares about is yet to
             | be reached. (More energy out than in.)
             | 
             | Good to hear that there's a laser design that might achieve
             | that.
        
               | ganbatekudasai wrote:
               | Don't take it too personally, but you, and many others
               | here, need to rethink their approach. You see a short
               | tweet without context about a topic you clearly know
               | nothing about (which is totally, fully okay, it's a
               | complex topic), and think you are now able to criticize
               | milestones in this impossibly complex topic.
               | 
               | Not even ask questions, not something like "hey, I saw
               | this tweet, I know it's just a tweet, but can someone
               | help me understand context?", no, you actually go ahead
               | and criticize work that you know nothing about, and when
               | confronted, you _double down_.
               | 
               | On some level, you must know yourself that it might be
               | better to ask as many unloaded questions as you want, but
               | otherwise sit this one out in terms of assessment.
        
               | sillysaurusx wrote:
               | No thanks.
               | 
               | I get that people are emotional about this, but it's
               | important to treat science with a critical eye.
               | 
               | The claim is that more energy came out than was put in.
               | This is false.
               | 
               | It's not just me saying it.
               | https://www.tiktok.com/t/ZTRVP5Pmg/
               | 
               | There is no "context" to understand. Yes, it's an
               | impressive feat. Yes, other laser designs might fix the
               | huge ignition costs. But _that hasn't happened yet_ , and
               | until it does, it's completely fair to point that out.
               | 
               | Will it win me any friends? Probably not. It's like
               | showing up to a party and saying the reason for the party
               | is mistaken. Very few people care.
               | 
               | But scientists should, and I am one. Doubly so for
               | incorrect reporting to laymen. We have a responsibility
               | to convey what was actually achieved, not what we wish
               | was achieved.
        
               | boc wrote:
        
               | LarryMullins wrote:
               | Your "honest feedback" is nothing more than naked
               | insults.
               | 
               | Sillysaurusx is right. The "impossibly complex" matter is
               | actually quite simple, Q=1 is little more than a
               | psychological milestone, not some sort of technical
               | tipping point where further progress becomes easier. And
               | they haven't even gotten to Q=1 unless you buy into the
               | justifications they give for dodgy accounting of the
               | energy they put into it. The "impossibly complex" matter
               | of commercial fusion is actually quite simple, it needs
               | to put out _a lot_ more energy than you put into it after
               | you _fully_ account for all the energy you put in. They
               | aren 't even close to this.
        
               | geysersam wrote:
               | You are entirely correct. I'll just add that it's not
               | only about the energy put in, but ultimately about the
               | cost. Net positive energy output is the absolute basic
               | requirement. We're not there, we're not close, and even
               | if we were, the hurdle would be to make it economically
               | viable.
        
               | twojacobtwo wrote:
               | Just as a note, since I made the same mistake initially,
               | the person you're replying to didn't make the post from
               | which you are quoting "impossibly complex".
               | 
               | It seems, to me, that boc was criticizing the
               | unnecessarily dour tone of sillysaurusx's previous
               | comment and not the technical aspect of the achievement.
               | 
               | The whole thing seems to come down to whether one
               | interprets the announcement as an attempt to deceive the
               | public at large or simply a celebration of a milestone
               | that many in the fusion research community have been
               | trying to achieve for a long time. I can understand it
               | being interpreted both ways, but I think the more
               | charitable interpretation is that science reporting, in
               | general, doesn't usually properly explain the levels of
               | nuance of various achievements and, as such, something
               | that is genuinely exciting for those in the community is
               | not necessarily as exciting for those outside of it -
               | which comes across as deceptive.
        
               | boc wrote:
               | When a baseball batter hits a ball at a record 120mph,
               | you calculate the impulse of force ([?]p) they put into
               | the swing to cause that result, not the total calories
               | the player consumed during the past year in order to
               | build their muscles.
               | 
               | You're arguing that the process of charging some
               | inefficient lasers (aka eating food throughout the year)
               | is invalidating this entire result. That was never part
               | of the experiment, nor is it relevant to this test.
               | 
               | I understand exactly what you wrote above, and I'm
               | telling you that it's not relevant to this discovery.
               | You're arguing a non-sequitur in the classic definition.
        
               | sillysaurusx wrote:
               | Which criticism am I dismissing?
               | 
               | People do seem to be getting emotional about fusion, and
               | pointing that out is hardly edgy.
               | 
               | Once fusion achieves more output than input, I'll be
               | celebrating right there with you. But until then,
               | ignoring the Doberman in the room is a worse look, from a
               | scientific standpoint.
               | 
               | I even cited a source from someone with a phd in
               | mathematical physics, who is likely far more qualified to
               | be talking about this than most of us here. So in terms
               | of dismissing criticism, the stack seems to be in the
               | other direction.
               | 
               | Scientific reporting matters. Reporting something false
               | is generally a bad idea. Saying "we got more energy out
               | than we put in" is false. Which link in this chain of
               | reasoning is invalid?
        
               | twojacobtwo wrote:
               | > It just seems a little strange to take credit for a
               | milestone when the milestone everyone cares about is yet
               | to be reached. (More energy out than in.)
               | 
               | That comment/criticism is a little strange in and of
               | itself. I would say it's the oddness or seeming petulance
               | of the above comment that brought on boc's comment.
               | 
               | A silly, but illustrative analogy:                 Kid:
               | Dad, look! I scored a home-run!         Father: Who
               | cares? Have you won the game yet? Stop celebrating until
               | you do something that everyone cares about!
        
               | geysersam wrote:
               | There's a difference between encouraging a kid and
               | discussing energy technology.
               | 
               | It's entirely valid to remark that fusion still is far
               | from viable as a source of energy.
        
               | twojacobtwo wrote:
               | I agree. To explain further, my post and the included
               | (noted silly) analogy were made with respect to
               | explaining the aspect of sillysaurusx's post(s) that boc
               | seemed to be criticizing.
        
               | simplicio wrote:
               | I think the confusion here is at least partially due to
               | most articles obscuring the primary purpose of the NIF.
               | Its not supposed to support commercial energy
               | development, its supposed to support nuclear weapons
               | development under the Nuclear Test Ban Treaty, where
               | testing bombs via setting them off is banned.
               | 
               | So the NIF is supposed to give a testbed to study
               | implosion created fusion reactions that produce enough
               | energy to "ignite", that is, propegate the reaction to
               | the rest of a hypothetical bomb. In that case, the amount
               | of energy needed for the infrastructure to produce the
               | initial implosion doesn't matter, what matters is that
               | the energy coming out is more then the actual energy that
               | triggered the reaction, so that the hypothetical bomb
               | would blow up and not fizzle.
        
               | geysersam wrote:
               | Exactly! It's so strange this is somehow made to be about
               | fusion as an energy source. I'm happy to announce that
               | Q>>1 has already been achieved on multiple occasions. In
               | the cores of the thermonuclear devices tested by the US
               | and USSR in the 50s. (Unfortunately that technology
               | proved unviable as a path to civilian fusion power.)
        
               | nilsbunger wrote:
               | It's a significant milestone because demonstrating you
               | can get net energy from the reaction removes a lot of
               | uncertainty of whether it's possible in the real world.
               | It starts to turn inertial fusion into an engineering
               | problem of how you increase the efficiency of each stage.
        
               | jacoblambda wrote:
               | Worth noting that the milestone achieved was positive
               | Q_plasma (more energy out of the plasma than in).
               | 
               | They are using inefficient lasers because they are
               | cheaper to buy/maintain/modify for research purposes.
               | 
               | Determining the conditions for positive Q_plasma is
               | largely a matter of science/research so the external
               | system doesn't matter as long as the variables are
               | controlled and results are reproducible.
               | 
               | Once positive Q_plasma is well understood/reproducible,
               | achieving positive Q_total (more energy produced than
               | spent running the infrastructure) is just a matter of
               | engineering and potentially waiting for the SOTA for
               | components (like lasers or materials) to catch up.
               | 
               | TLDR: This is the scientists proving the theory. Now it's
               | the scientists' job to refine the theory. Then the
               | engineers get to put it into production.
        
               | moloch-hai wrote:
               | The theory was proven to everybody's satisfaction in
               | 1950.
               | 
               | There will be no production, except of new, smaller
               | thermonuclear warheads. That is their legislated remit.
        
               | kelnos wrote:
               | It _is_ a milestone, and I do think the researchers
               | deserve credit for that. Getting more energy out of the
               | reaction than was delivered to it by the lasers _is_
               | actually important.
               | 
               | No one (except perhaps poor science "reporters") is
               | claiming that this means we now have free and cheap
               | fusion power. Of course the energy put in to operate the
               | lasers themselves needs to be accounted for -- and it is!
               | -- but that doesn't make what they've achieved useless.
               | It's also useful to remember that the researchers
               | involved are not the people writing press releases and
               | articles; let's not minimize their achievement just
               | because of sloppy, sensationalist reporting.
               | 
               | I like the analogy downthread of a kid being excited
               | about scoring a home run in baseball, but the dad
               | chastising the kid for celebrating before actually
               | winning the game. That's what it feels like is happening
               | here.
               | 
               | This is a huge step in the right direction, and it should
               | be celebrated as such.
        
             | worik wrote:
             | Why are they using these "flash pumped" lasers if more
             | efficient ones are available?
        
               | londons_explore wrote:
               | It's a very old lab, and replacing them isn't cheap/easy.
               | 
               | You don't need to use efficient lasers to get the
               | scientific results they're after - other people have
               | already very accurately measured the properties of modern
               | lasers, so we can predict how they would perform without
               | having to actually use them.
        
               | jcarreiro wrote:
               | Because they are researching inertial confinement fusion,
               | not trying to build a working power plant. The efficiency
               | of the lasers doesn't matter, since it doesn't affect
               | their research.
        
               | Aeolun wrote:
               | Is energy on the order of 300MJ so cheap? You'd think
               | that cutting it down to 150MJ would allow them to do more
               | experiments.
        
               | nrki wrote:
               | 300MJ ~= 83kWh which is like, $2000 in CA
        
               | IanCal wrote:
               | I think you're out by some orders of magnitude. With the
               | current energy issues in the UK it'd be under PS100.
               | Other things suggest in California it's more like 20
               | cents per kWh so were you thinking ~$20?
        
               | nrki wrote:
               | You're right of course, messing up my units again.
        
               | kragen wrote:
               | 300 megajoules is 83 kilowatt hours
               | 
               | a typical power price at trading hubs is US$40 per
               | megawatt hour, though this varies considerably depending
               | on many factors and is sometimes actually negative
               | 
               | a typical retail price is US$120 per megawatt hour
               | 
               | so this is about US$10 worth of electrical energy
        
               | beowulfey wrote:
               | It's a proof of concept. Upgrading lasers that already
               | work is not necessarily the best use of limited funds.
        
               | ClumsyPilot wrote:
               | They could get higher power out of more efficient lasers,
               | enabling research at higher energies or bigger targets
        
               | 988747 wrote:
               | Not to mention the money they would save on electricity
               | bills.
        
               | belltaco wrote:
               | The electricity bill is like $2000. It'd waste more money
               | for a manager to _think_ about how to replace equipment,
               | at California pay rates. This whole thread is making me
               | lose faith in HN.
        
               | insane_dreamer wrote:
               | Actually 83 KwH costs only about $20 in CA (avg $0.25 /
               | KwH and probably LRL pays even less.
        
               | kelnos wrote:
               | That's not the purpose of the research, though. They are
               | solely focusing on the energy transfer between the lasers
               | themselves, and the output from the reaction. It's not
               | clear that higher energies or bigger targets will teach
               | us anything new.
               | 
               | Upgrading the lasers would slow the project down as new
               | hardware is installed and issues are worked out. Not to
               | mention I doubt the new hardware is cheap, and may be
               | more expensive than burning excess energy using old laser
               | tech in the meantime.
               | 
               | Other research groups work on laser efficiency, and the
               | "final product" using this method (if it ever proves
               | viable) would put together all the best pieces to get the
               | best efficiencies.
        
           | Rebelgecko wrote:
           | It was discussed a lot in the threads about this yesterday,
           | but apparently the lab had relatively inefficient lasers.
           | Newer ones are an order of magnitude more efficient
        
             | petilon wrote:
             | This is what I captured from the press conference:
             | 
             | 300 megajoules was used to generate the laser (this is also
             | captured in [1]). They also mentioned that newer lasers
             | have 20% wall plug efficiency. If so, they need to improve
             | the energy output by 5x in order to break even relative to
             | wall plug energy consumption.
             | 
             | [1] https://techcrunch.com/2022/12/13/world-record-fusion-
             | experi...
        
               | rtpg wrote:
               | So if we had the 20% wall plug efficiency, then we need
               | that 3.2:2 ratio to become 10:2 to hit break-even. That
               | looks like a huge gap but maybe there are tricks here
               | that resolve this once you get over the initial gap.
        
               | LarryMullins wrote:
               | That's just the lasers, the rest of the plant needs power
               | too. Big water pumps are big power hogs, as is the rest
               | of the supporting equipment that any power plant requires
               | to operate. _Far_ over  "wall plug" break even is
               | required for commercial viability.
        
               | ncfausti wrote:
               | _Just_ bootstrap a second fusion power plant with the
               | first, then continue on, similar to how compilers for a
               | language can be written in the language itself.
        
               | jameshart wrote:
               | "Wall plug energy consumption"
               | 
               | I don't know why but this caused me to picture Alec from
               | Tech Connections in a few years time, showing off his
               | fusion laser plugged in to a kill-a--watt, while he
               | explains carefully, through the magic of buying two of
               | them, why you can get more power out than you put in, and
               | why these old inertial confinement fusors were pretty
               | neat actually.
        
         | hackernewds wrote:
         | The funding does seem miniscule given we spend 100x more on
         | funding military excursions in the name of energy security
        
           | azinman2 wrote:
           | Is the bottleneck for fusion money though?
        
             | ClumsyPilot wrote:
             | There are like 20 designs of various fusion reactors on the
             | drawing board that need to be built and tested.
             | 
             | Scientists also don't work for free. They arent mushrooms
             | that grow by themselves
        
               | nerpderp82 wrote:
               | One of the things that I think I noticed from the press
               | conference, is that funding is going to be the bare
               | minimum to meet some goal for a design they select.
               | 
               | This seems like a gross mistake.
               | 
               | If we are going to avert a climate catastrophe we will
               | need TW of power to "unburn" the carbon we put into the
               | environment (ocean and atmosphere). Instead of barely
               | hitting this target, we should over deliver since we are
               | running out of wall-clock time.
               | 
               | Every project that meets a bar for feasibility,
               | organizational/operational capabilities (if they dont
               | have it, either fix it, or transfer design to capable
               | team) should be given funding (50-100M). We should be
               | dropping BILLIONS on this, if we can drop 50B+ on
               | semiconductors we can do the same for fusion.
        
               | LarryMullins wrote:
               | Dump trillions of dollars into fusion energy today and it
               | will still be decades before the first fusion power plant
               | is connected to the grid. You'd be better off funding the
               | construction of fission power plants. Those are very
               | expensive and take years to build, but they're still a
               | hell of a lot cheaper and faster than funding fusion to
               | the degree you're suggesting.
        
               | moloch-hai wrote:
               | Each dollar diverted to chase nuke wills-o'-th'-wisp
               | brings climate catastrophe nearer.
               | 
               | Money is fungible. Dropping $billions on this means _not_
               | dropping those $billions on something that works already,
               | works fantastically well, and would work even better with
               | more money. We already know how to prevent (more) climate
               | catastrophe. We just need to do more of it.
        
               | salawat wrote:
               | So drop it on fission. There. Settled.
        
               | moloch-hai wrote:
               | Fission means, in practice, paying enough for coal
               | generation, over the decade, to have built enough solar
               | to displace the nuke; and paying many times that, on top,
               | to build the nuke.
               | 
               | So, no. Each dollar diverted from building out solar to
               | mining coal or fooling with nukes brings existential
               | catastrophe nearer.
        
               | kamaal wrote:
               | Beginner question, why is it hard(not possible) to
               | calculate the gain without actually building a reactor?
               | 
               | Surely if you have a non-satisfactory yield you shouldn't
               | be building it. And that should be possible to estimate
               | before we spend billions on it?
        
               | blincoln wrote:
               | Simulations and estimations about processes in the
               | physical world always leave room for surprises when one
               | is doing things that haven't been done before.
        
             | rowanG077 wrote:
             | money is always the bottleneck in some sense. There are
             | diminishing returns but in general more money will make it
             | happen faster.
        
               | fullshark wrote:
               | The laws of physics also a limiting factor
        
               | JKCalhoun wrote:
               | You might be right -- we threw enough money and put
               | humans on the Moon. The Manhattan Project was well funded
               | and produced results as well.
        
               | hcknwscommenter wrote:
               | I believe the Manhattan project (where we basically built
               | an entire new city, and entire new manufacturing process
               | from scratch: mining operations, refineries, enrichment,
               | milling, etc.) cost less in constant dollars than the
               | stealth fighter.
        
               | ErrantX wrote:
               | They also had a strong ideological element too.
        
               | [deleted]
        
               | dmix wrote:
               | The talent + purpose (which drew the talent) was what
               | defined Manhattan. The money came easy when all of the
               | greatest minds in the country were pointing a giant
               | flashing light in one obvious direction.
               | 
               | This is big news but fusion will largely be a product of
               | the people it attracts. The people can do the job
               | attracting money and other talent if it's justified.
               | 
               | I've seen the Canadian gov try to throw money at trying
               | to build a local tech scene and it all went to hucksters,
               | old school finance suits with megacorp resumes, and
               | administrators. While all the tech talent just kept going
               | to SF where the capital was going into high risk
               | ventures... not expensive buildings, events,
               | 'entrepreneur/small business programs', and propping up
               | old school D-round investors. Money is easily wasted even
               | when the pursuit sounds noble and valuable on the
               | surface.
        
               | maria2 wrote:
               | This is like saying thread count is always the bottle
               | neck in computation. More money allows more parallelism
               | as you can pay for more people and more equipment for
               | more research. As in computing, there are diminishing
               | marginal returns and surely a version of Amdahl's Law for
               | human endeavors.
        
               | xattt wrote:
               | > thread count is always the bottle neck in computation
               | 
               | The softer the bed linen, the more rested the computer
               | scientists will be and the more likely they are to come
               | up with novel solutions that lead to faster computing.
        
               | [deleted]
        
               | BuckRogers wrote:
               | I would have to agree. The "in general" though is
               | carrying an enormous amount of weight in that statement.
               | 
               | I think what other commentors may be getting at is that
               | in many cases the simple analogy of asking how 9 women
               | can have a baby in 1 month is instructive here. You could
               | throw trillions at that problem, a need to have a baby in
               | 1 month. Sometimes there are hard limits that money has a
               | hard time addressing.
               | 
               | A case could be made that with enough money put towards
               | advanced technology, like gene therapy to force a fetus
               | to maturity in 1 month vs 9, it could be done with
               | horrendous side effects.
               | 
               | So to your point money does solve all problems, but I
               | think diminishing returns is putting it very lightly.
        
             | z3phyr wrote:
             | More money attracts more eyes, hands, grey matter which
             | they would otherwise focus on something with more money.
             | But it is a long process.
        
             | rrrrrrrrrrrr2 wrote:
             | I think a major bottleneck for fusion research from the lay
             | public (including myself) is lack of interest.
             | 
             | Fission reactors work really well and have been around for
             | 50+ years. If we are going to go nuclear instead of
             | renewable, we need to address the elephant in the room.
             | 
             | The elephant in the room is: why not just fission?
        
               | azinman2 wrote:
               | Fukushima most recently
        
               | [deleted]
        
             | jacoblambda wrote:
             | yes. fusion funding has been sliding downwards for decades
             | which is a large reason why it takes so long to do
             | anything.
             | 
             | It's largely the same reason why NASA takes so long to do
             | anything.
             | 
             | 1. Shortage of funding
             | 
             | 2. failure can result in loss/exhaustion of funding
             | 
             | 3. extremely low risk tolerance
             | 
             | 4. physical experiments needing new HW only happen when the
             | likelihood of success is extremely high
             | 
             | 5. projects are over engineered to reduce chance of failure
             | 
             | 6. projects are over budget and over schedule
             | 
             | 7. projects only make minor incremental progress
             | 
             | 8. lack of fast/exciting progress drives decrease in
             | funding
             | 
             | 9. GOTO 1
        
               | kortilla wrote:
               | It has nothing to do with funding. SpaceX had far less
               | than NASA.
               | 
               | For another example from a different angle, the military
               | has limitless supplies of funding but innovates even less
               | than NASA.
        
               | ClumsyPilot wrote:
               | You are comparing company that makes trucks with a
               | company that makes precision scientific instrumers, and
               | you are declaring that truck companu is more efficient
               | per kilo of produce. this is stupid.
               | 
               | Nasa develops nuclear reactors, landed on titan and has
               | reached pluto. Spacex vehicle has never left the Earth-
               | moon system.
        
               | kortilla wrote:
               | Lol "spacex makes trucks". Way to throw on the anti-Musk
               | blinders and completely ignore the back-half of the
               | comment and misunderstand the first half.
               | 
               | Also, spacex has launched outside of the earth-moon
               | system. It was a roadster
        
               | ClumsyPilot wrote:
        
               | mynameisvlad wrote:
               | SpaceX is not Tesla. It's disingenuous to call SpaceX a
               | "company that makes trucks". Just like NASA, they also
               | make precision scientific instruments. They're the first
               | privately funded mission to the ISS and run a massive
               | satellite constellation.
               | 
               | They may not have the same accomplishments as NASA, but
               | they're _far_ from a  "company that makes trucks".
        
               | ClumsyPilot wrote:
               | > Just like NASA, they also make precision scientific
               | instruments.
               | 
               | Which scientific instruments does SpaceX make? I have
               | never heard of a single one.
               | 
               | In contrast, curiosity rover has dozens.
               | 
               | https://youtu.be/GUQ91fdYbP4
        
               | mynameisvlad wrote:
               | You think their satellite fleet has absolutely no precise
               | equipment for knowing and maintaining its position? Or
               | for communicating with terminals and each other?
               | 
               | Like, _come on_. I get shitting on Musk is the cool new
               | thing, but this is genuinely the case where SpaceX is
               | doing cool things in space, and at an extremely fast
               | pace. Get over yourself if you can't see through your
               | Musk hate and only see them as "a company that builds
               | trucks".
        
               | ftlio wrote:
               | The analogy is apt in at least defining a separation
               | between the overall complexity of what SpaceX produces
               | compared to NASA, to say something of how the two
               | different models of R&D work, but maybe off in degrees as
               | you discussed.
               | 
               | "NASA makes precision scientific instruments and SpaceX
               | makes precision scientific instruments that have higher
               | tolerances with a higher focus on throughput, and there
               | are rapidly diminishing returns in how much funding can
               | be used to close the gap" is probably the right take if
               | not as fun.
        
               | oittaa wrote:
               | > Spacex vehicle has never left the Earth-moon system.
               | 
               | https://www.whereisroadster.com/
        
               | yreg wrote:
               | Not your typical space vehicle
        
               | zaroth wrote:
               | I can't agree that _funding_ is  "largely the reason" why
               | NASA takes so long to do anything. I doubt funding is a
               | top 3 reason.
               | 
               | NASA just isn't about high-risk / high-reward "moonshots"
               | anymore. The overarching political environment doesn't
               | allow it, never mind the office politics.
               | 
               | NASA will get back to the moon using easily an order of
               | magnitude more funding than it should have taken, with a
               | launch system that costs an order of magnitude more money
               | for each launch than it should. (almost two?)
        
               | krainboltgreene wrote:
               | > I can't agree that funding is "largely the reason"
               | 
               | > NASA just isn't about high-risk / high-reward
               | "moonshots" anymore. The overarching political
               | environment doesn't allow it, never mind the office
               | politics.
               | 
               | Why doesn't the political environment allow for it. What
               | could happen. What could regulatory bodies do to NASA for
               | taking a risk and failing. What sort of constricting
               | change could political bodies do in such a situation.
        
               | LarryMullins wrote:
               | > _Why doesn 't the political environment allow for it.
               | What could happen._
               | 
               | Three astronauts were incinerated alive. That was when
               | they started to take safety more seriously. Subsequent
               | accidents have only reinforced this.
        
               | krainboltgreene wrote:
               | Yes, but what happened after the astronauts died as a
               | response?
               | 
               | The entire point of my comment is that funding cuts
               | happened. That is the reaction.
        
               | ngcc_hk wrote:
               | The funding senator became the administrator of the
               | current moon attempt. The funding insist on using the old
               | technology in the funding. All these sounded bad. If nasa
               | has more freehand. But then the fund will not get back to
               | the states ...
        
               | BobbyJo wrote:
               | Have to +1 this. A lot (most?) of NASA's funding is
               | directed toward keeping people employed and skilled, as
               | opposed to accomplishing goals, as with a lot of
               | government money. NASA could do a LOT more with the
               | funding they already have, if they were willing to divest
               | from older technologies and vendors, but the politics of
               | its funding doesn't allow that.
        
               | krainboltgreene wrote:
               | > A lot (most?) of NASA's funding is directed toward
               | keeping people employed and skilled, as opposed to
               | accomplishing goals
               | 
               | This is so hilarious wrong I don't even know where to
               | start.
               | 
               | > but the politics of its funding doesn't allow that.
               | 
               | The post _that you are agreeing with_ says that
               | "funding" is not the reason for their plan.
        
               | BobbyJo wrote:
               | > This is so hilarious wrong I don't even know where to
               | start.
               | 
               | Anywhere at all would be better than nowhere. I worked
               | for a defense contractor for a few years, so I'm basing
               | my comment on my experience there.
               | 
               | > The post that you are agreeing with says that "funding"
               | is not the reason for their plan.
               | 
               | Not sure what you are saying here.
        
               | jacoblambda wrote:
               | I agree however that culture was caused by a lack of
               | funding.
               | 
               | You can't be swift and lean when you are given very
               | limited, budgeted funding. You can't take risks or you
               | risk putting people out of a job and killing the program.
               | 
               | That leads to an overly conservative culture that
               | restricts any risk taking and over-engineers everything
               | to the point failure is effectively impossible.
               | 
               | This slow movement, overly conservative, design by
               | committee approach helps limit risk but it absolutely
               | balloons costs in the long run and horrifically delays
               | progress. Of course if they were a company they'd
               | eventually run out of money but that's not really an
               | option for gov orgs so when the overly conservative,
               | limited run designs end up encountering production
               | issues, the projects explode in cost with nearly no upper
               | limit.
               | 
               | TLDR: The political climate is a direct consequence of
               | the lack of budget and continued restriction of that
               | budget only worsens the problem.
        
               | ufmace wrote:
               | "Funding" isn't really a good answer IMO. I don't know a
               | ton about Fusion research specifically, but NASA is
               | horrifically inefficient with money compared to private
               | competitors. Giving them more money won't magically make
               | them more efficient. Reasons why include:
               | 
               | - Their incentive is to optimize for political approval,
               | which means spreading facilities among as many
               | congressional districts as possible, which creates a ton
               | of inefficiency from poor communication and the need to
               | constantly ship things around
               | 
               | - Public approval is the goal and failure is the worst
               | possible option, so things tend to be optimized to take
               | as few engineering risks as possible and have huge
               | amounts of bureaucracy to spread the blame for any
               | possible failure
               | 
               | There's a reason why SpaceX started landing rockets with
               | a fraction of the money that NASA spent on building
               | ridiculous boondoggles.
        
               | shawn-butler wrote:
               | >> Their incentive is to optimize for political approval,
               | which means spreading facilities among as many
               | congressional districts as possible, which creates a ton
               | of inefficiency from poor communication
               | 
               | Ummm.. I thought remote work was no less efficient?
        
               | [deleted]
        
               | geysersam wrote:
               | Also, SpaceX did it 60 years later.
        
         | nabla9 wrote:
         | 3.15 Mj = 0.875 kWh
         | 
         | the unsolved issue with laser fusion (ICF) as an energy source
         | is the fast degradation of high powered lasers. High powered
         | beam degrades optics on it's path and those things are
         | expensive. ITER has similar problem with superconducting
         | magnets.
        
         | moffkalast wrote:
         | > demonstrating the scaling laws at work
         | 
         | One would think that one look at the sky would be enough to say
         | that "hey this fusion thing scales pretty well".
        
         | zardo wrote:
         | The targets are really the secret sauce right? If there were a
         | civil ICF for power program, would NIF designs and data even be
         | available to help, or is it all classified?
        
           | jkelleyrtp wrote:
           | There are pictures of CAD and experimental setups for the
           | targets. They're also pretty open with the setup numbers, so
           | in theory, you could make your own NIF setup and try to get
           | their target designs working.
           | 
           | From what I understand, a lot of the work from the past years
           | has been trying to piece together geometries, pulse timing,
           | stability, and quality of targets.
        
         | bmmayer1 wrote:
         | This is a stupid question but I don't know anything about
         | fusion:
         | 
         | How is it possible for X energy to create X+Y energy in output?
         | Doesn't that violate some fundamental law of physics?
        
           | garfieldnate wrote:
           | I think it's more like a release of potential energy; kind of
           | like how you can lightly nudge a large object teetering on
           | the edge of a cliff and it'll make a huge splash at the
           | bottom. It took a lot of energy to create the big splash, but
           | you didn't need much to trigger it.
        
           | ceejayoz wrote:
           | You're using X energy to release Y energy _from the fuel_
           | (the pellet, containing deuterium and tritium). It was there
           | already, just not in a usable form.
        
           | [deleted]
        
           | xdavidliu wrote:
           | sometimes, when two small particles fuse, they become a
           | single larger particle, but the larger particle's mass is
           | slightly less than the sum of the masses of the two smaller
           | particles. The slight difference becomes energy released, and
           | the amount of energy released, roughly speaking, is E = mc^2.
        
           | simiones wrote:
           | The energy is "released" from the binding energy of the
           | nuclei. It's similar to how throwing a bottle of
           | nitroglycerine can generate a huge explosion, even though you
           | use a tiny amount of energy to throw it.
        
           | spullara wrote:
           | If you look at the mass before of their fuel, 1 deuterium
           | atom + 1 tritium atom:                   2.01410177811 u +
           | 3.01604928 u = 5.03015105811 u
           | 
           | vs the mass of the fusion products of 1 helium atom and 1
           | neutron:                   4.002602 u + 1.008 u = 5.010602 u
           | 
           | You'll notice that even though we started with 5 neutrons and
           | 2 protons and ended up with the same number there was some
           | additional binding energy that is unaccounted for in the new
           | configuration. This is the energy released by the fusion
           | reaction via E = mc^2. Here we see the mass difference is:
           | 5.03015105811 u - 5.010602 u = 0.01954905811 u
           | 
           | Converting that to energy you find that is 17.6 MeV. As you
           | go up the periodic table fusing nuclei you will get less and
           | less marginal energy until you get to iron where at that
           | point fusion become net negative and fission is then takes
           | over where breaking nuclei apart gains energy, marginally
           | more as you go up the periodic table. That's why you want to
           | fuse light particles and fission very heavy particles. It is
           | also why there is so much iron as it is kind of the base
           | state of both of these reactions.
        
             | eklitzke wrote:
             | Tangentially related, but I think this is an interesting
             | fact, all the atoms in our universe/galaxy/solar system
             | with a mass up to that of iron are formed in the core of
             | stars in stellar fusion. Hydrogen fuses into helium, and as
             | a star nears the end of its lifetime you get heavier
             | elements like lithium, carbon, and so on. Under normal
             | stellar fusion no elements heavier than iron will be
             | produced, and iron is only element number 25. If you just
             | looked at nucleosynthesis through the lens of stellar
             | fusion, it isn't obvious that there should be any heaver-
             | than-iron atoms at all in the universe.
             | 
             | These heaver-than-iron elements are created in a very
             | interesting and exotic process. When a large enough star
             | dies it explodes in a supernova, and a _huge_ amount of
             | energy and neutrons are released in a very short period of
             | time. This supernova generates enough energy and neutron
             | material that small amounts of heavier elements like gold,
             | platinum, etc. are created through exotic nuclear fusion
             | reactions, even though these heavy fusion reactions are
             | energy-absorbing.
             | 
             | It's interesting to think when you're wearing jewelry made
             | from gold or platinum, all of those atoms in your jewelry
             | were created during the death of a star.
        
               | jmartrican wrote:
               | So that means that for life to form, we probably need a
               | star to die so that the heavier atoms used in complicated
               | life forming chemical reactions (correct me if i am wrong
               | here as what I'm about to say depends on it), hence it
               | could be the case that if the universe is 13.5 billion
               | years old, then we humans are appearing in the universe
               | at the earliest possible time.
               | 
               | 13.5 billion years seems like the time required to create
               | a star, have the star die and blow up, have all that
               | material settle and create a new star, then the planets
               | are formed, than enough time on one of those planets
               | needs to pass for life to form, then complicated life.
        
               | marcyb5st wrote:
               | Not necessarily. First generation stars were,
               | theoretically, enormous both due to low metallicity of
               | the collapsed medium and a higher average concentration
               | of said medium. These stars lifespans were extremely
               | short, shorter that blue giants we see today. So novas
               | due to the death of these stars happened fairly early in
               | the lifespan of the universe (talking about few million
               | years after the big bang).
               | 
               | Therefore, life could have developed in a few tens to few
               | hundreds of millions of years after the big bang. That's
               | still true even if we assume that heavier elements are
               | created mainly when neutron stars collide and not by
               | super/hypernovas as we theorized before LIGO/Virgo
               | observatories.
               | 
               | Consequently, we likely are not a "progenitor"
               | civilization in the universe if we only consider planets
               | formation. We might not see anyone out there either
               | because there's a great filter for intelligent life to
               | emerge (so the bottleneck is in our past) or because
               | few/no civilizations get to have an impact on their host
               | stars (the filter is in our future) that would allow us
               | to see them.
        
               | hnuser123456 wrote:
               | Basic life (single-celled?) requiring the elements above
               | lead might have a chance at that time, but complex life
               | like us wouldn't do so well if there were still
               | supernovas going off left and right. There's a theory
               | with decent evidence that at least one of the mass
               | extinctions was caused by a supernova:
               | https://www.space.com/supernova-caused-earth-mass-
               | extinction...
               | 
               | That being said, I wasn't aware of how LIGO changed the
               | understanding of how heavier elements are usually formed,
               | guessing it changed the expected neutron star prevalence?
               | Do you have any additional reading on that?
        
               | kubanczyk wrote:
               | > how LIGO changed the understanding of how heavier
               | elements are usually formed, guessing it changed the
               | expected neutron star prevalence?
               | 
               | It's not about the prevalence, but about the light curves
               | observed during the event AT 2017gfo. They indicate
               | significant heavy metal ejection but, what's interesting,
               | also _production_.
               | 
               | > mergers of neutron stars contribute to rapid neutron
               | capture (r-process) nucleosynthesis
               | 
               | These two articles cite the relevant papers:
               | 
               | https://en.wikipedia.org/wiki/GW170817#Scientific_importa
               | nce
               | 
               | https://en.wikipedia.org/wiki/Nucleosynthesis#Neutron_sta
               | r_c...
        
               | marcyb5st wrote:
               | You are right about supernova hampering life evolution,
               | but it's unclear how long the fireworks lasted. In my
               | comment I argued that it is possible to have the
               | conditions of life emerge much earlier than 13.5 billion
               | years. Not that it necessarily happened.
               | 
               | Regarding the second point have a look at
               | https://www.ligo.org/science/Publication-
               | GW170817Kilonova/in... . That isn't my field of
               | specialization, so I am not sure about recent
               | publications. At the time though this was a big deal as
               | kilonovas seem to be the primary source of heavy nuclei
               | in the universe. That particular event crested between
               | 1/100th to 1/1000th solar masses worth of heavy ( heavier
               | than iron) nuclei. This is a greater rate than supernovas
               | estimations.
        
               | maxbaines wrote:
               | Very much a laymen also, however funnily enough I was
               | listening to a bbc program called in our time, a couple
               | of nights ago, where a similar topic was discussed one
               | comment was that life is carbon based and for carbon to
               | exist a star has to die, so yes therefore we are in the
               | early stages. Will try to fin the episode....
        
               | heavyset_go wrote:
               | > _13.5 billion years seems like the time required to
               | create a star, have the star die and blow up, have all
               | that material settle and create a new star, then the
               | planets are formed, than enough time on one of those
               | planets needs to pass for life to form, then complicated
               | life._
               | 
               | Maybe for a main sequence star, but there other processes
               | that involve nucleosynthesis.
        
               | short_sells_poo wrote:
               | I'm just a layman but I believe by the time our sun has
               | formed, we've gone through multiple star cycles. The
               | early stars were very pure - made basically purely of
               | hydrogen (maybe some helium?). They were huge, burned
               | very bright and died comparatively quickly. Each time
               | stars died, more heavy elements (and heavier elements
               | than before) were produced. Over time the heavy element
               | content (called metallicity) has increased in all stars.
               | I believe there are also theories of white dwarf mergers
               | undergoing runaway fusion and a lot of heavy elements
               | being generated during the explosion.
               | 
               | You raise an interesting question though: what is the
               | earlier point of time where the heavy elements were
               | abundant enough for life (as we know it) to form? Just
               | because we started existing at +13.5 billion years, it
               | doesn't mean carbon based life couldn't have formed much
               | earlier.
        
               | rtsil wrote:
               | That assumes that life as we know it is the only possible
               | form of life.
        
               | matt-attack wrote:
               | I have zero ability to answer your question but I would
               | love to know about about this. If life (like we know it)
               | requires the explosion of aged stars, what is the
               | earliest it would take. What is the minimum time needed
               | to form, grow and explode a single star? Has there been
               | time for this to occur 10s, 100s of times since the Big
               | Bang? (obviously they can happen in parallel, but I'm
               | thinking about how many in series).
        
               | caf wrote:
               | There's a large range of stellar lifetimes, from a few
               | million years up to trillions of years.
        
               | andrewflnr wrote:
               | Not necessarily, but look up the phosphorus problem.
        
               | b33j0r wrote:
               | It's funny that alchemy was kinda onto something, but
               | underestimated the energy requirements by orders of
               | magnitude of orders of magnitude
        
               | hgsgm wrote:
        
               | BizarroLand wrote:
               | True, all you need to turn lead into gold is a moderately
               | powerful collider and some hydrogen.
               | 
               | The conversion is also very slow. And expensive. To make
               | it this way it would cost a Quadrillion dollars an ounce.
               | 
               | https://www.scientificamerican.com/article/fact-or-
               | fiction-l...
        
               | unnouinceput wrote:
               | Quadrillion now, but costs will drive down and once is
               | turned to gold, it stays gold. In the far future where
               | all gold was mined this will be the only process left to
               | get more. Or explode stars and capture gold from them.
        
               | kennend3 wrote:
               | I joke with my Son all the time about turning Mercury
               | into gold (He works in the nuclear industry).
               | 
               | Once you get past the enormous energy costs to do this
               | you have a secondary problem, all the gold produced this
               | way is radioactive and it beta decays to.. Mercury.
        
               | blibble wrote:
               | > all the atoms in our universe/galaxy/solar system with
               | a mass up to that of iron are formed in the core of stars
               | in stellar fusion.
               | 
               | all is a strong word
               | 
               | for example: the nuclear fusion experiment in the
               | article, that would have produced a few atoms heaver that
               | hydrogen
               | 
               | (not to mention all the nuclear bombs that had a fusion
               | stage)
        
               | 867-5309 wrote:
               | _we are all made of star stuff_
        
               | pishpash wrote:
               | Star stuff sounds like some German element.
        
               | emmelaich wrote:
               | Exactly what I thought! I checked with google translate.
               | 
               | star stuff = sternzeug. stern stoff = star fabric
        
               | hibbelig wrote:
               | Stoff had more than one translation into English. One is
               | cloth. Another refers to substances. Eg hydrogen is
               | called Wasserstoff in German: water-stuff
        
               | dejj wrote:
               | See "waterstuff" in the Uncleftish Beholding:
               | 
               | https://www.ling.upenn.edu/~beatrice/110/docs/uncleftish_
               | beh...
        
               | agumonkey wrote:
               | yet we all want to be
        
               | maerF0x0 wrote:
               | or as I like to say to encourage myself that small things
               | matter
               | 
               | "Stars are made of quarks"
        
               | rhacker wrote:
               | What are quarks made of?
               | 
               | https://static.wikia.nocookie.net/memoryalpha/images/d/d9
               | /Qu...
        
               | schiffern wrote:
               | >all the atoms in our universe/galaxy/solar system with a
               | mass up to that of iron are formed in the core of stars
               | 
               | Note that this is not, strictly speaking, true.
               | 
               | Roughly 90% of the helium atoms in the universe were
               | created via Big Bang nucleosynthesis.
               | 
               | https://en.wikipedia.org/wiki/Big_Bang_nucleosynthesis
        
               | ajross wrote:
               | Actually current modeling has supernovae as being only a
               | small contributor to the measured abundance of heavy
               | nucleii. These guys tend to come from a more exotic
               | source still: material thrown off as a _neutron star is
               | tidally disrupted during a merger event with another
               | neutron star or black hole_.
               | 
               | The wikipedia page is pretty good, as always:
               | https://en.wikipedia.org/wiki/Nucleosynthesis
               | 
               | Almost everything with mass of 90 or above comes
               | predominantly from neutron star mergers, basically.
        
               | MayeulC wrote:
               | After all, is there anything better to create new
               | elements than a hot, dense neutron soup?
        
               | short_sells_poo wrote:
               | I'm always fascinated by the sheer and unfathomable
               | amounts of energy that is thrown around in these events.
               | Just thinking about the fact that a single spoonful of
               | neutron star matter contains more mass than Mount Everest
               | fills me with wonder about the world we live in.
        
               | galangalalgol wrote:
               | What happens whena tablespoon of neutron soup gets thrown
               | out of the well of a neutron star? Does it suddenly
               | expand to the size of everest? Where do the electrons
               | come from?
        
               | caf wrote:
               | In terms of "where do the electrons come from", an
               | ordinary neutron in free space has a half-life of about
               | 10 minutes, decaying through beta decay which produces a
               | proton, an electron and a neutrino.
        
               | galangalalgol wrote:
               | That sounds fairly energetic... So after 10min you'd have
               | some odd mix of heavy elements probably approaching a
               | decent fraction of the volume of everest. Half the volume
               | of everest x (densityofgranite / densityoflead)
               | 
               | That kind of expansion rate has to rival any explosion
               | imaginable.
        
               | heavyset_go wrote:
               | I'd imagine some of the energy and degenerate matter
               | consisting of neutrons would convert to protons and
               | electrons, and nucleosynthesis would take place to form
               | elements.
               | 
               | I have no idea, though, but I'm pretty sure I watched a
               | video about this.
        
               | ajross wrote:
               | It's essentially a giant atomic nucleus, so absent a
               | star's worth of gravity holding it together it's going to
               | decay rapidly into stable isotopes. So essentially it
               | would act more or less the same as a huge fission bomb of
               | the same mass.
        
               | Mistletoe wrote:
               | Good Lord the universe is old. To think of how rare all
               | that must be and how it had to have time to somehow get
               | here to our planet.
        
               | clavalle wrote:
               | If they weren't here, we wouldn't be able to talk about
               | it.
               | 
               | I'd be interested to know if we're in an element rich
               | vein of the wider universe or if all the good stuff is
               | more or less evenly distributed?
        
               | moloch-hai wrote:
               | Phosphorus is supposed to be rare in the wider world.
               | Considering how central it is to everything important,
               | life might find it very difficult to start in our
               | temperature range, without.
        
               | Mistletoe wrote:
               | I'm not sure but this has some interesting info such as-
               | 
               | >Some whole galaxies have average metallicities only 1/10
               | of the Sun's. Some new stars in our galaxy have more
               | metals in them than the original solar nebula that
               | birthed the Sun and the planets did. So the amount of
               | "metals" like oxygen and carbon can vary by a few orders
               | of magnitude from star to star, depending upon it's age
               | and history.
               | 
               | https://www.reddit.com/r/askscience/comments/9tujxn/are_t
               | he_...
        
               | qbrass wrote:
               | Heavier elements supposedly come from two neutron stars
               | colliding because even a single star exploding isn't
               | enough energy.
               | 
               | So think about two stars killing each other to make your
               | jewelry.
        
               | stock_toaster wrote:
               | "The nitrogen in our DNA,        the calcium in our
               | teeth,        the iron in our blood,        the carbon in
               | our apple pies       were made in the interiors of
               | collapsing stars.       We are made of star stuff".
               | - Carl Sagan
        
               | [deleted]
        
               | steam_raven wrote:
               | We have calcium in our bones,        iron in our veins,
               | carbon in our souls,        and nitrogen in our brains.
               | 93 percent stardust,       with souls made of flames,
               | we are all just stars        that have people names"
               | Nikita Gill
        
               | tomdekan wrote:
               | I find this poem inaccurate.
        
               | andrepd wrote:
               | ?
        
               | fnordpiglet wrote:
               | Souls are clearly not made of both carbon and flames.
        
               | moloch-hai wrote:
               | The ones in Hell could be.
        
               | gretch wrote:
               | I understand this is a poem that is focused on artistic
               | expression and not scientific accuracy, but I find the
               | line about "carbon in our souls" to be out of place. I
               | guess the rest of the poem is incidentally correct (when
               | not abstract)
        
               | guelo wrote:
               | You could define soul as the fuel engine for life, which
               | is basically burning carbon. As long as that furnace is
               | functioning you're alive == you have a soul.
        
               | ok_dad wrote:
               | One who is a materialist could argue that your "soul"
               | comes from the stuff you're made out of, so your "soul"
               | probably has carbon it somewhere.
        
               | alchemyromcom wrote:
               | >Carbon in our souls
               | 
               | I think it might be an allusion to alchemy. Basically,
               | the alchemists believed that ash (what was left after
               | burning something) was the soul of all things...And--
               | this is where my complete lack of understanding about
               | science shows-- I'm pretty sure Ash has lots of carbon?
               | It's, you know, poetic. Many have claimed that poems are
               | the "language of paradox" so it's okay for it to be a
               | little non-literal. My interpretation of it, though, is
               | that the soul is something impure that you must burn
               | away, or maybe that the soul is polluted by our own words
               | and behavior. It's definitely not meant to be
               | scientifically accurate.
        
               | kragen wrote:
               | ash has no carbon
               | 
               | carbon's oxides are all gaseous at standard temperature
               | and pressure
        
               | lliamander wrote:
               | Not quite. Plenty of carbon is release as carbon oxides,
               | but calcium carbonate is also a major component of ash
               | (or at least wood ash).
        
               | kragen wrote:
               | good point
               | 
               | little carbon, then, not none
        
               | elihu wrote:
               | Going by what wikipedia says, wood ash can have carbon.
               | If I understand correctly, how much depends largely on
               | how hot it burned.
               | 
               | https://en.wikipedia.org/wiki/Wood_ash#Elemental_analysis
        
               | dr_dshiv wrote:
               | Sure, the word "soul" comes from the proto Germanic
               | "saiwiz" (for sea or ocean).
               | 
               | But not because "you are like a drop in the ocean," but
               | because "you are like an ocean in a drop."
               | 
               | The idea of soul can be objectionable when it is based on
               | an immortal being or on a vitalist life-force (like
               | "anima" of the Latin). But it seems fine when it is based
               | on the psyche (like the "Psuche" of the Greek).
               | 
               | I embrace taboo words like soul because they 1. are
               | common 2. are useful for referring to things that seem
               | pretty important (like avoiding soulless companies or
               | products or buildings) and 3. are challenging to my
               | normal (scientific) understanding of the world.
               | 
               | Still, I'd be more comfortable if the poem referred to
               | the "carbon of our souls" rather than "carbon in our
               | souls." Hmm...
        
               | hgsgm wrote:
               | Was that originally in a different language? "Heart"
               | makes more sense than "soul", and could be translates
               | loosely.
        
               | fknorangesite wrote:
               | Oh wait I can play this game:
               | 
               | You and I are complicated but we're made of elements Like
               | a box of paints that are mixed to make every shade They
               | either combine to make a chemical compound or stand alone
               | as they are
               | 
               | - They Might Be Giants
        
               | eru wrote:
               | If I understand this right, I think some of the lighter
               | than iron elements are also created in those exotic
               | processes. But yes, unlike for the heavier-than-iron
               | elements, the lighter ones are _also_ created in normal
               | stellar fusion.
        
               | SiVal wrote:
               | Iron is always spoken of as the dividing line, but I'd
               | like to know whether iron is _exactly_ on the line, on
               | one side (which?), or it depends. IOW, does fusion of
               | iron atoms release energy (hydrogen side of the line),
               | absorb energy (uranium side of the line), neither, or
               | either (depending on conditions)?
        
               | kennend3 wrote:
               | My son has a masters in nuclear physics and i've always
               | been curious as to why iron causes stars to explode.
               | 
               | He does an excellent job explaining things and put it to
               | me like this.
               | 
               | Elements to the Left of Iron can undergo fusion and
               | release energy, Elements to the right can undergo fission
               | and release energy.
               | 
               | Iron IS the line because it needs energy to do either of
               | these.
               | 
               | All elements want to find stability, and Iron is that
               | Element because it needs energy for either fission or
               | fusion.
               | 
               | So yes, Iron is the dividing line and this is what makes
               | it so stable.
               | 
               | Edit: forgot to link the chart when referencing left or
               | right..
               | 
               | http://www.splung.com/content/sid/5/page/benergy
        
               | dTal wrote:
               | Fusion to the left of Fe, fission to the right, here I am
               | stuck in the middle with glu(ons)
               | 
               | (Yes I know it's technically mesons at the scale we're
               | talking about but it doesn't rhyme so there)
        
               | soheil wrote:
               | Mesons should been called gluons, way stickier for sure.
        
               | eropple wrote:
               | As I understand it, iron is the first element that
               | absorbs energy under fusion, and therefore won't fuse
               | further. Could be wrong, though.
        
               | moloch-hai wrote:
               | It will happily fuse further. It just won't support the
               | outside of a star against gravity, while doing it. So the
               | star collapses, fuses lots more stuff even heavier than
               | iron, and then explodes. Most of the iron and heavier
               | stuff fuses into the core of a neutron star, the ultimate
               | in energy-consuming fusion.
        
               | kennend3 wrote:
               | None of this is accurate.
               | 
               | Iron will not happily fuse further because this NEEDS
               | energy and where would that energy come from?
               | 
               | "heavier than iron" elements are produced when a star
               | explodes because that collapse produces enormous amounts
               | of energy.
               | 
               | During the collapse, the outer edge of the star is
               | accelerated to something like 20% of the speed of light,
               | that is an ENORMOUS amount of energy slamming down on the
               | core.
               | 
               | Lastly, neutron starts don't produce energy, they are the
               | incompressible remnants of a dead star.
        
               | moloch-hai wrote:
               | You answer your own question: the energy for further
               | fusion, all the way to neutron degeneracy, is provided by
               | gravitational collapse. The outer layers fusing provide
               | energy for the explosion.
        
               | whycome wrote:
               | The periodic table is pretty awesome. But I wonder if
               | there's a layout that takes into account this
               | fission/fusion division? Would it just be a line?
               | 
               | -- Yeah there are a few alternative designs, but nothing
               | that seems to do the division.
               | https://en.wikipedia.org/wiki/Alternative_periodic_tables
        
               | martopix wrote:
               | That's because the periodic table is essentially about
               | chemistry (i.e. about electron orbitals), not about
               | nuclear physics (i.e. the atom's nucleus). For example it
               | doesn't talk much about isotopes, aside from usually
               | reporting the average atomic mass.
        
               | whycome wrote:
               | My point is that there are other ways of organizing the
               | same information to perhaps reveal unexpected
               | connections. From the same link, a 'physicists periodic
               | table' - https://en.wikipedia.org/wiki/Alternative_period
               | ic_tables#Th...
               | 
               | And really, i guess everything is physics if you get
               | specific enough.
        
               | mnl wrote:
               | Look at the binding energy curve:
               | http://hyperphysics.phy-
               | astr.gsu.edu/hbase/NucEne/nucbin.htm...
        
               | 29athrowaway wrote:
               | It is also interesting that the Milky Way will collide
               | with Andromeda and then we will be invaded by zerg.
        
             | joe-collins wrote:
             | And on a total tangent, this fact played a part in
             | worldbuilding done by the author L. E. Modesitt, Jr.
             | 
             | > When I initially decided to write _The Magic of Recluce_
             | in the late 1980s, I 'd been writing science fiction
             | exclusively... I conveyed a certain dismay about the lack
             | of concern about economic, political, and technological
             | infrastructures in various fantasies then being written and
             | published in the field...
             | 
             | > I faced the very real problem of creating a magic system
             | that was logical... Most fantasy epics have magic systems.
             | Unfortunately, many of them, particularly those designed by
             | beginning authors, aren't well thought out, or they're
             | lifted whole from either traditional folklore or gaming
             | systems and may not exactly apply to what the author has in
             | mind.
             | 
             | > I began by thinking about some of the features and tropes
             | of traditional fantasy. One aspect of both legend and
             | folklore that stuck out was the use of "cold iron" to break
             | faerie magic, even to burn the creatures of faerie, or to
             | stand against sorcery. Why iron? Why not gold or silver or
             | copper? Not surprisingly, I didn't find any answers in
             | traditional folklore or even contemporary fantasy. Oh,
             | there were more than a few examples, but no real
             | explanations except the traditional ones along the lines of
             | "that's just the way it works."
             | 
             | > For some reason, my mind went back to astronomy and
             | astrophysics and the role that nuclear fusion has in
             | creating a nova... Each of these fusion reactions creates a
             | heavier element and releases energy... The proton-proton
             | reaction that produces iron, however, is different, because
             | it is an endothermic reaction...
             | 
             | > At the same time, the fact that metals such as copper or
             | silver conducted heat and electrical energy suggested that
             | they were certainly less than ideal for containing
             | electrical energy. Gold and lead, while far heavier than
             | iron, do not have iron's strength, and other metals are too
             | rare and too hard to work, particularly in a low-tech
             | society.
             | 
             | > At this point, I had a starting point for my magic
             | system. I couldn't say exactly what spurred this
             | revelation, but to me it certainly made sense. Iron can
             | absorb a great amount of heat. If you don't think so, stand
             | on an iron plate barefoot in the blazing sun or in the
             | chill of winter. Heat is a form of energy. In fantasy,
             | magic is a form of energy. Therefore, iron can absorb magic
             | and, by doing so, bind it.
             | 
             | https://www.lemodesittjr.com/the-books/saga-
             | recluce/recluce-...
        
             | aaroninsf wrote:
             | This is an A+ comment--helpful, well-formatted, concise,
             | with bonus interesting additional detail.
             | 
             | Thank you.
        
               | qorrect wrote:
               | Yes well done .
        
               | spullara wrote:
               | Thanks, finally got to use my physics masters degree.
        
               | zaroth wrote:
               | First time for everything!!
        
             | subsubzero wrote:
             | Do we know how much tritium is needed for a city's energy
             | generation? What about a state etc? Reason I ask is the
             | only uses I have seen for tritium is on old watch dials
             | made in the pre-90's. Curious how much of this resource is
             | out there.
        
               | adgjlsfhk1 wrote:
               | TLDR is there isn't nearly enough tritium, but fusion
               | reactors can make more (while still generating energy)
        
               | ngcc_hk wrote:
               | Can you collect them easily in the reactor ?
        
               | elihu wrote:
               | If I understand correctly, tritium is the result of
               | bombarding lithium with neutrons.
               | 
               | I'm not sure how tokomaks are expected to work; do you
               | just add lithium and expect the tritium to get where it
               | needs to go to keep the reaction going, or do you
               | actively remove gases from vessel, filter out the
               | tritium, and re-use it as fuel?
               | 
               | Either way, I don't imagine it'd be too hard to recapture
               | the stuff.
               | 
               | https://en.wikipedia.org/wiki/Breeding_blanket
        
               | yonaguska wrote:
               | Tritium is very popular on gun sights as well- as it's a
               | glow in the dark sight that doesn't need to be charged.
               | I'm now questioning the practice of appendix carrying
               | with tritium sights.
        
               | ars wrote:
               | Tritium decays by beta-decay (an electron). The electron
               | can not travel very far in air (1/4 inch), and is stopped
               | by even the thinnest piece of metal. It's even stopped by
               | the dead outer layer of your skin.
               | 
               | i.e. it's completely harmless unless you eat it.
        
               | XorNot wrote:
               | Not quite: beta decay will penetrate the skin enough to
               | damage living tissue - beta burns are what caused the
               | fatalities of the Chernobyl first responder fire
               | fighters.
               | 
               | They spent a few hours covered in dust on their coats,
               | and did a bunch of subsurface skin damage which
               | manifested as third degree burns. Sepsis, not radiation
               | poisoning, generally killed them.
        
               | dublin wrote:
               | Well, it lasts for several years, but considerably less
               | than even a human lifetime: Tritium's half-life is only
               | about 11 years, so gun sights, dark-proof glow-in-the-
               | dark signage (usually reserved for critical industrial
               | plants, ships and offshore platforms due to expense),
               | etc, will become seriously degraded in just a few years.
               | (Since the glow is directly proportional to the remaining
               | low-level beta radioactivity, which can barely penetrate
               | the glass envelope in the first place - you'd get more
               | radiation (from radium) living in a brick house than
               | carrying 24-7.)
               | 
               | FWIW, tritium and a phosphor granule encapsulated in
               | glass microspheres have been developed for self-
               | illuminating runway paint, but again, no one really uses
               | it because tritium is stupid expensive, and again, it'
               | loses half its brightness in only a decade.
               | 
               | On the other hand, I've been told that Trijicon will
               | replace their tritium gun sights for the lifetime of the
               | original owner. I plan to live long enough to cost them
               | money...
        
               | binkHN wrote:
               | > Tritium's half-life is only about 11 years, so gun
               | sights ... will become seriously degraded in just a few
               | years.
               | 
               | We'll all be using RDSs by then ;) ?
               | 
               | > ...I've been told that Trijicon will replace their
               | tritium gun sights for the lifetime of the original
               | owner.
               | 
               | I didn't know this, thanks.
        
               | S04dKHzrKT wrote:
               | Real Engineering recently made a video that covers fuel
               | needs.
               | 
               | https://www.youtube.com/watch?v=BzK0ydOF0oU
        
               | phtrivier wrote:
               | And the (otherwise excellent) channel is supposed to soon
               | post an adv... I mean informer... I mean "exclusive
               | documentary" about "repeat after me we're totally not a
               | scam - we just play one on YouTube" fusion startup
               | Helion.
               | 
               | Which I'm going to watch, because even though everything
               | I hear about this company gives me insane Theranos
               | vibes... Well, if they pull it off... They might light a
               | bulb with fusion in my lifetime.
        
               | adaml_623 wrote:
               | The Helion approach seems plausible to me. Can you point
               | me towards some of the sources that give you vibes?
        
               | phtrivier wrote:
               | A recent episode on Matt Ferrel's Undecided [1]
               | 
               | (And I though I had seen a similar segment on "Answer
               | with Joe", but I can't find it.)
               | 
               | None of those would be opposable source, of course -
               | there won't be any until they open a plant, publish data,
               | etc...
               | 
               | In the meantime, I see a hype cycle brewing, and it makes
               | me a bit uncomfortable - but, we'll see.
               | 
               | [1] https://youtu.be/yNP8by6V3RA
        
               | twic wrote:
               | Take spullara's numbers:
               | 
               | 2.01410177811 u = 3.34449439340696e-24 g deuterium
               | 
               | 3.01604928 u = 5.008267217094e-24 g tritium
               | 
               | 17.6 MeV = 7.832863e-19 kWh energy
               | 
               | Divide through, and you will see that you need 4.27
               | ug/kWh of deuterium, and 6.39 ug/kWh of tritium.
               | 
               | A random source [1] says that New York will use 50.6 TWh
               | per year by 2027. That would require ~216 kg/yr of
               | deuterium and ~323/yr kg of tritium.
               | 
               | This is all assuming 100% efficiency. A quick read
               | suggests 50% efficiency might be practical, so double
               | those quantities.
               | 
               | Also, i could easily have messed up that calculation
               | somewhere, so please do check it!
               | 
               | [1] https://www.buildingcongress.com/advocacy-and-
               | reports/report...
        
               | rerdavies wrote:
               | Tritium has a half-life of 12 years so there is no deep
               | pool of tritium upon which to draw. The primary source of
               | tritium on earth is cosmic-ray interactions in the upper
               | atmosphere that produces 7.5Kg of tritium a year
               | worldwide.[1]
               | 
               | Isn't that going to cause a serious problem if it
               | requires 323Kg/yr of tritium just to power New York City?
               | 
               | [1] https://www.sciencedirect.com/topics/earth-and-
               | planetary-sci...
        
               | wizofaus wrote:
               | Apparently no, because it can be made by the fusion
               | process itself, via contact with lithium, and there's
               | enough proven reserves of the latter to supply us for
               | 100s of years.
        
               | moloch-hai wrote:
               | Nobody knows how to get tritium at PPB concentration from
               | the thousand tons of radioactive molten FLiBe it is
               | dissolved in. You have to process all of it every day
               | because you need that tritium for fuel tomorrow.
        
               | BadBadJellyBean wrote:
               | I wonder if that is much or not. I have no idea how hard
               | this is to produce. Do you have an idea about that?
        
               | mbauman wrote:
               | Oooof, looks like the primary way of creating it is
               | through... fission reactors.
               | 
               | https://en.wikipedia.org/wiki/Tritium#Production
               | 
               | And there's not much of it:
               | 
               | > According to a 1996 report from Institute for Energy
               | and Environmental Research on the US Department of
               | Energy, only 225 kg (496 lb) of tritium had been produced
               | in the United States from 1955 to 1996.[a] Since it
               | continually decays into helium-3, the total amount
               | remaining was about 75 kg (165 lb) at the time of the
               | report.
        
               | davidklemke wrote:
               | The concentration of deuterium in the ocean is about
               | 150-160 parts per million and with 1233.91 quintillion
               | liters covering the earth we have approximately
               | 8.2260667e+12kg worth of it to extract, so we've got a
               | bit to work through!
               | 
               | Tritium however is far more rare with only trace amounts
               | of it being available within nature and barely more than
               | a kg produced per year. Producing the 100s of kgs
               | required per year still seems to be an unsolved problem,
               | although my quick searching shows there's a couple viable
               | solutions for it.
        
               | mlyle wrote:
               | The solution is that fusion power plants can breed
               | tritium and become net producers of it...
               | 
               | Though in practice enough will be lost that probably
               | they'll still be somewhat net consumers-- just not nearly
               | to the extent predicted by a simple thermodynamic model.
               | 
               | Still, even if fusion becomes a net producer of tritium,
               | the whole tritium-is-hard-to-get problem will likely be a
               | constraint that we'll be fighting as we ramp up use of
               | fusion power in the future.
        
               | wizofaus wrote:
               | That such a small amount of matter could generate so much
               | power is pretty remarkable. I might be way off base but
               | from what I can find online it seems you'd need over 2000
               | times as much uranium?
        
               | w0mbat wrote:
               | Tritium is also used in gun sights.
        
             | riemannzeta wrote:
             | Great comment. But you meant 2 helium atoms and 1 neutron
             | in the second equation, correct?
        
               | spullara wrote:
               | Nope. Helium has 2 protons and 2 neutrons. Here is an
               | image that shows the reaction:
               | 
               | https://www.energy.gov/sites/default/files/styles/full_ar
               | tic...
        
             | infogulch wrote:
             | > It is also why there is so much iron as it is kind of the
             | base state of both of these reactions.
             | 
             | I always thought this is the interesting takeaway, both
             | fusion and fission _funnel_ their constituent matter
             | _towards_ iron, as the final stable state of matter. Far
             | future civilizations will have a _lot_ of iron on their
             | hands.
        
           | benevol wrote:
        
           | [deleted]
        
           | nkrisc wrote:
           | Mass and energy are equivalent. You're using X energy to
           | reduce the mass of your fuel and converting that mass into Y
           | energy. When X < Y you have useful energy production at the
           | cost of the mass of your fuel. Energy is conserved.
           | 
           | The reason nuclear fusion is such a desirable goal is because
           | it only takes a relatively small amount of mass to convert
           | into a relatively large amount of useful energy, and the mass
           | (the fuel) is relatively easy to obtain.
           | 
           | Like all energy generation, it's converting one type of
           | energy into another, more convenient type, to do useful work.
           | Like a hydroelectric dam converting the potential energy of
           | water into more useful electrical energy. Energy is conserved
           | when water spins a turbine, it's just that electrical energy
           | is more _useful for work_ than the potential energy of the
           | water. Of course you can still use the potential (or kinetic)
           | energy of the water directly, such as with a water mill. But
           | the energy to work ratio is worse in that form (especially if
           | the work to be done is far away from the watermill).
           | 
           | Whenever you build a fire you need to input some amount of
           | energy to begin the chemical reaction that releases energy.
           | In this instance we get not electrical energy, but energy in
           | the form of infrared and visible light, to heat our home and
           | light our way. Yet the total energy released by the fire far
           | surpasses the energy you used to start the reaction, but
           | because the wood's mass is consumed, energy is ultimately
           | conserved. You have converted wood (not useful for heating
           | your home) into infrared light (useful for heating your
           | home).
        
             | lr1970 wrote:
             | > Mass and energy are equivalent.
             | 
             | Mass is energy at rest, hence equivalence with exception of
             | massless particles like photons that have zero mass and
             | non-zero energy. Also, photons travel with the speed of
             | light in vacuum and cannot be found at rest in any frame of
             | reference. Modern physics is fun, isn't it?
             | 
             | P.S. Neutrinos were thought to have zero mass as well, but
             | according to the Standard model they have mass.
        
               | nkrisc wrote:
               | Yeah, my explanation is very much simplified.
        
           | jperras wrote:
           | Energy is released when two atomic nuclei combine to form a
           | larger atomic nuclei.
           | 
           | There's a threshold of energy required to attain this fusion
           | reaction (otherwise there would be no light nuclei in the
           | universe), and once the nuclei combine there's energy that is
           | released, similar to how some chemical reactions can be
           | exothermic in nature.
        
           | delaaxe wrote:
           | Latest xkcd: https://xkcd.com/2710/
        
           | tekla wrote:
           | You have a piece of wood. You ignite it with a match. This
           | causes a self sustaining reaction in the form of fire that
           | releases far more energy than the match could ever create.
           | 
           | This is effectively what is happening with any energy
           | generator.
        
           | [deleted]
        
           | syngrog66 wrote:
           | E = mc^2
           | 
           | the "extra" comes from the mass
        
           | karpierz wrote:
           | You take a lighter and light gasoline on fire, using X
           | energy. Then once the gasoline catches on fire, it'll burn on
           | its own, releasing Y energy.
           | 
           | Same principle, different means.
        
           | dsfyu404ed wrote:
           | You know how when you burn something you release the energy
           | in the chemical bonds?
           | 
           | Fusion and fission are like that but for atoms instead of
           | molecules.
        
             | jameshart wrote:
             | Except... chemical bonds don't 'store' energy. Molecules
             | are a _low energy configuration_. It takes energy to rip
             | them apart!
             | 
             | But, O2 molecules, with their double bond, don't take much
             | energy to break apart. If they do, and then pair up with
             | say a bunch of Hydrogen and Carbon atoms that were nearby
             | in some long chain or something, they form bonds that are
             | stronger - that take more energy to break - and you end up
             | with some leftover energy. Water and CO2 molecules are an
             | even lower energy configuration.
             | 
             | but the extra energy you get wasn't exactly 'in' the oxygen
             | bond though - any more than when you have a ball at the top
             | of a hill it has potential energy 'in' it.
        
               | dsfyu404ed wrote:
               | There's a fundamental tradeoff between technical
               | precision and explaining things in a way that's relatable
               | to simpler stuff. Deal. With. It.
        
               | davrosthedalek wrote:
               | Not if the original description is exactly the opposite
               | of what happens. You get energy out by making stronger
               | bonds.
        
               | m55au wrote:
               | Stronger bonds by definition are lower energy bonds. So
               | you get energy out by making the total bond energy go
               | lower or "releasing it".
        
           | 867-5309 wrote:
           | equally confusing is the BBC article which mentions the
           | energy used for the reaction does not include the energy
           | needed to power the lasers, which renders it a net loss
        
           | rmbyrro wrote:
           | Nothing is being actually "created", just converted.
        
           | a-priori wrote:
           | It's not "creating" energy, it's _releasing_ energy.
           | 
           | The original atoms (exactly which atoms depends on the
           | reactor, but let's assume it's deuterium and tritium) have a
           | certain starting energy. When you fuse them together the
           | resulting atom (helium-4, if you start with deuterium and
           | tritium) moves it into a _lower_ energy state.
           | 
           | Since the fused atom has lower energy than the input atoms,
           | the fusion reaction releases the difference in energy, which
           | you can then capture.
        
           | dpacmittal wrote:
           | Same way you use spark plug to get the engine going in an ICE
           | car
        
           | eru wrote:
           | The analogy is that settings a pile of wood on fire requires
           | a small amount of fire to start a big fire.
           | 
           | Energy in total is still conserved, but it makes engineering
           | sense to compare the size of the starting fire to the total
           | inferno created.
        
           | wodenokoto wrote:
           | I think you should think of it as "this lumber only needs 1
           | match to light it on fire while that lumber requires 10
           | matches to get started."
        
           | steve76 wrote:
        
           | paxys wrote:
           | The input energy X is used to create the conditions of high
           | temperature and pressure that are needed for fusion to take
           | place.
           | 
           | When fusion happens, two hydrogen atoms fuse together into
           | one, losing a bit of mass in the process. The mass difference
           | is converted into energy Y (using E=mc2).
           | 
           | In this case, Y was greater than X, so there was a net gain
           | in useful energy.
        
           | emmelaich wrote:
           | The answers you got are excellent but a short response might
           | just say you don't start with just X energy.
           | 
           | In a sense it's no more mysterious (conservation of energy-
           | wise) than adding the energy of a spark results in the energy
           | of the wood fire.
           | 
           | i.e. energy is transformed, not created as you quite
           | accurately write.
        
           | ihaveajob wrote:
           | A daily life parallel: You can use a lighter to put a small
           | amount of energy into a bunch of wood to extract more energy
           | than you put it. In the case of fusion, this energy is coming
           | from fusing hydrogen atoms, rather than a chemical reaction.
        
           | elif wrote:
           | to answer essentially,
           | 
           | because matter is energy, you can use conversion energy to
           | turn matter into its stored energy.
        
           | [deleted]
        
           | anigbrowl wrote:
           | Y is the energy that was holding some hydrogen atoms together
           | which you have liberated (while destroying the atoms in
           | question but that's OK cause it's abundant).
        
           | Sporktacular wrote:
           | The Y comes from the mass of matter converted in to energy.
           | The mass of the material before the reaction is greater than
           | the mass of its products.
           | 
           | The law you're referring to might be the conservation of
           | energy, but that applies to non-nuclear reactions and is more
           | accurately called the law of conservation of mass-energy. In
           | this case the energy in times the mass at the start is still
           | equal to the energy out times the mass at the end. For the
           | energy to increase, the mass must decrease to produce the Y
           | in your equation.
        
           | [deleted]
        
           | jackmott wrote:
        
       | sergiotapia wrote:
       | The future just got a whole lot brighter for my children. This is
       | going to save our planet, not funky wind farms.
        
         | loeg wrote:
         | This a commercially viable power source ain't.
        
         | adamvalve wrote:
         | No need to pit them against each other. This achievement wasn't
         | certain. Multiple paths towards a more sustainable future is
         | better for everyone.
        
           | lostmsu wrote:
           | > Multiple paths towards a more sustainable future is better
           | for everyone.
           | 
           | That is debatable.
        
       | einpoklum wrote:
       | US DOE: Excessive uncritical media hype achieved.
        
       | helpm33 wrote:
       | 3.15 MJ is equivalent to 1.5 lb TNT, so it was quite a bang in
       | their target chamber. Just for comparison, it's also just short
       | of one kWh, so it would run an electric car for about three-four
       | miles.
        
       | rurban wrote:
       | So for how many milliseconds did it run? Those things are
       | incredibly unstable, I see only one private US company making the
       | stability breakthrough
        
       | JoeAltmaier wrote:
       | Huge!
       | 
       | So much left to do. Capture that output energy. Streamline the
       | machinery that produced the result. Do it at scale and
       | efficiently.
       | 
       | But that's just engineering, as they say. Which is one thing we
       | are pretty good at!!
        
       | e1g wrote:
       | Recently discussed https://news.ycombinator.com/item?id=33945863
       | [740 comments]
        
       | trilobyte wrote:
       | Am I reading it correctly that they achieved a ~53% output of
       | energy over input?
        
         | gjsman-1000 wrote:
         | 2.05 MJ in, 3.15 MJ out.
         | 
         | That's amazing.
        
           | eastbound wrote:
           | Minus the laser power supply, is it correct?
        
             | pciexpgpu wrote:
             | What would it take to store/feedback the gained (converted)
             | energy to power the lasers? Sort of like a bootstrap with a
             | very inefficient source of power, and over time transition
             | to the produced clean energy?
             | 
             | Armchair scientisting aside, this news seems like the most
             | exciting news over the past few years - a great way to end
             | this year (/pandemic). We are far out from a production-
             | ready thingy, but if it took decades for brilliant
             | scientists to conjure up this initial clunky toy thingy, I
             | am sure an army of scientists/companies would work at
             | building the real thing much, much faster: we had _only_ a
             | freaking 8086 not 30 years ago!!
             | 
             | We have the basic blueprint from government funded research
             | no less.
        
             | maria2 wrote:
             | Yes. The lasers are supplied with 400 megajoules, but it's
             | a start.
        
             | gjsman-1000 wrote:
             | Press release states: "meaning it produced more energy from
             | fusion than the laser energy used to drive it."
             | 
             | The 2.05 MJ put into the reaction includes the laser power
             | supply then, it would seem, unless they are bad at press
             | releases. But 2.05 MJ is not a lot of power.
        
               | prewett wrote:
               | If I remember from the article/discussion from yesterday,
               | "laser energy" is the energy in the laser beam, but
               | creating that 2 MJ laser beam required 200 MJ.
        
               | JumpCrisscross wrote:
               | > _creating that 2 MJ laser beam required 200 MJ_
               | 
               | NIF uses notoriously inefficient lasers. They lase fine.
               | Just not efficiently. From what I've seen, that 200 MJ
               | would be closer to 20 MJ with modern equipment.
               | 
               | Still a gap! And there is still making the fuel, making
               | and replacing the reactor as well as collection losses.
               | But we're within two orders of magnitude of system break
               | even, which is closer than we've ever been.
        
               | sidibe wrote:
               | 2.05 MJ is what made it into the system from the laser.
               | It took a lot more to power the laser.
        
               | trilobyte wrote:
               | That's what I was trying to figure out. So is it still a
               | net-negative overall?
        
               | anfilt wrote:
               | Yea very curious as well would need to dig a little
               | deeper. If it's the beam energy it means we need more
               | efficient lasers or to scale larger to overcome the
               | energy losses from making a laser beam.
               | 
               | Still even if it's just the beam we are at an energy
               | positive which is still great news because it mean the
               | fundamentals are working.
               | 
               | Still other issues though, the biggest in my opinion are
               | an effective way to produce Tritium and energy
               | extraction.
        
               | trilobyte wrote:
               | Looks like the Nature article
               | (https://www.nature.com/articles/d41586-022-04440-7) is
               | more clear about it still being a net loss. Still an
               | important step forward, but it's important to
               | contextualize it.
        
               | pelorat wrote:
               | It's a net negative with a factor of 400 or so. This
               | breakthrough is not really a breakthrough, it's just
               | marketed as such because NIF needs to justify their
               | funding. Compressing pellets of fusion fuel using lasers
               | has no chance of ever forming the basis of a nuclear
               | reactor.
               | 
               | It's scientifically interesting because a self-sustaining
               | reaction (until the fuel was consumed that is) was
               | achieved in a lab setting (as opposed to in a hydrogen
               | bomb). There might be fusion plasma data in there that
               | are of importance to more serious attempts at actually
               | building fusion reactors.
        
               | trynewideas wrote:
               | If it was net-positive today they'd already be plugging
               | it into the grid.
        
         | [deleted]
        
         | phkahler wrote:
         | >>:Am I reading it correctly that they achieved a ~53% output
         | of energy over input?
         | 
         | Let's add some words. The output energy is electromagnetic
         | radiation and heat. When they do make a conversion to usable
         | energy (electricity) there will be conversion losses.
         | 
         | On the input side, they are measuring laser energy. The lasers
         | are not very efficient so this overlooks a bunch of losses on
         | the input side as well.
         | 
         | They are probably 100x away from real energy gain, and the
         | facility isn't even designed to be used that way.
         | 
         | Never the less, it is a milestone along the way.
        
       | Kukumber wrote:
       | Every breakthroughs starts from government (people) funded
       | initiatives, congrats to everyone involved, a future without the
       | need to generate selfish profit is at reach!
        
         | coliveira wrote:
         | Well, they'll clearly give the government-backed science to
         | some "visionary" who will promptly monopolize the tech and hail
         | himself as super-genius who brought energy to the masses!
        
         | hardnose wrote:
         | Every breakthrough starts from government funded initiatives?
         | Wilbur and Orville Wright disagree.
        
           | Kukumber wrote:
           | Without the accessibility of their public library, and public
           | workers to guide them, they would have never been able to
           | acquire the required knowledge in aeronautics
        
             | hardnose wrote:
             | Isn't that a bit like saying that every innovation depends
             | upon milk? I guess, technically, every innovation does
             | begin with a baby drinking milk, but it seems like a
             | stretch to attribute the innovation to the milk, rather
             | than to the mind of the individual who may or may not have
             | been fueled by milk?
        
               | Kukumber wrote:
               | > it seems like a stretch to attribute the innovation to
               | the milk, rather than to the mind of the individual who
               | may or may not have been fueled by milk?
               | 
               | What ever it been fueled with, knowledge wasn't created
               | at an individual's birth, it's an accumulation of a
               | collective and shared effort
               | 
               | The point i was trying to make in my post is; it always
               | starts from the people, for the people to continue, for
               | the people to achieve a civilizational ascension
               | 
               | If we build the means to generate infinite energy for
               | free, then we'll have to ask ourselves if giving that
               | much power to the individual a safe endeavor, or if we
               | should make sure the prospect is for the collective to
               | ascend
               | 
               | Thanks to this achievement, many will learn from it and
               | acquire knowledge to pursue that goal, would it be the
               | case if it was a solo for profit effort? i doubt it
               | greatly
               | 
               | The open source tech industry thrives because it's a
               | collective and shared effort, funding issue persists but
               | that's due to us, individuals, living civilization's
               | transition, it'll be a solved problem shortly
        
           | stonogo wrote:
           | I don't think they do, since they started with research done
           | by the Smithsonian Institution.
        
             | hardnose wrote:
             | Do you have any source information for this? As far as I
             | understood, the Wright brothers started out by building
             | hobbyist gliders in consultation with fellow aviation
             | pioneer Octave Chanute.
             | 
             | I checked the Wikipedia entry, but the only reference it
             | maintains for the Smithsonian having helped the Wright
             | brothers is that they apparently gave Wilbur an award in
             | 1910, after having tried unsuccessfully _to steal credit
             | from him for building the first heavier than air flyer_.
             | Somehow I doubt that 's the kind of government contribution
             | to innovation to which the previous poster intended to
             | refer.
        
               | stonogo wrote:
               | https://airandspace.si.edu/exhibitions/wright-
               | brothers/onlin...
               | 
               | Wilbur Wright asked for the Smithsonian's aeronautical
               | research. They still have the letter. The very Wikipedia
               | article you're referencing, in the exact paragraph you're
               | talking about, contains the words "Orville Wright, whose
               | brother had received help from the Smithsonian when
               | beginning his own quest for flight." https://en.wikipedia
               | .org/wiki/Wright_brothers#Smithsonian_fe...
               | 
               | Sure, the Smithsonian people were assholes about it. That
               | doesn't negate their contribution to the Wright brother's
               | work. Incedentally, in modern timesif you visit the Air
               | and Space Museum you can see the exhibit where they own
               | up to the shabby attempt to promote their late leader
               | over the Wrights. They cover the feud pretty thoroughly
               | -- including having both aircraft.
        
             | carabiner wrote:
             | Yeah but the Wrights were following research from all over
             | the world, including England and Germany. You might as well
             | say that the Wrights were also funded by the British
             | government.
        
               | stonogo wrote:
               | Yes, that's how research works. What's your point?
        
               | carabiner wrote:
               | The Wrights didn't start from a government-funded
               | initiative. Using govt resources, like public roads or
               | receiving public schooling as a child doesn't make every
               | subsequent output a "government initiative." This is
               | semantics at this point though. You've made up your mind,
               | and so have I, and you're obviously sitting on this
               | thread to rapid fire rebut on this Tuesday night. Here
               | you go, have the last reply:
        
         | typeofhuman wrote:
         | How much of the funded research is actually a breakthrough?
        
         | ralusek wrote:
         | Some breakthroughs.
        
       | xyst wrote:
       | One more step towards getting away from dirty fossil fuels.
       | 
       | I just hope we have enough time to see it implemented at scale
       | (ie, powering entire states/cities/towns/municipalities, swapping
       | infra in place).
       | 
       | I also hope the O&G industry doesn't attempt to block this with
       | fake science (ie, decades of climate denial, greenwashing via
       | "recycling" campaigns).
        
       | daxfohl wrote:
       | My pessimistic self feels like the short-term effect is that it
       | sets a deadline by which oil companies know they have to extract
       | and sell all the existing oil on the planet, and a doubling down
       | on increased emissions now because fusion will solve it
       | eventually.
        
         | chrisco255 wrote:
         | There are hundreds of years worth of oil deposits (possibly
         | more) even at current usage rates. "Selling all the oil" isn't
         | in the realm of possibility.
        
           | daxfohl wrote:
           | Still, as much as possible before the party is over.
        
             | chrisco255 wrote:
             | As much as necessary, sure. Oil it turns out is pretty
             | useful in many different industries and contributes to
             | higher standards of living for the vast majority of the
             | world. It isn't some inherently evil technology or
             | resource. Still, it's going to take decades to transition
             | to electric regardless of any breakthroughs in the
             | meantime.
        
       | panosfilianos wrote:
       | I tried to do some back-of-the-envelope calculations on what this
       | means in regards to energy costs being saved, because I couldn't
       | find a direct source (maybe GPT could help actually).
       | 
       | Anyway, based on ITER [1] to equate the energy production of a
       | 1000MW coal plant you would need 2.7t of coal for that plant or
       | 250kg of deuterium and tritium for the fusion reactor (split
       | equally). Based on [2] deuetrium costs about ~$15k a kg. But
       | tritium is ridiculously expensive, at $30k per gram (!) [3].
       | 
       | This leads to a calculation of ~$700M for the coal plant and
       | ~$3.75B for the fusion plant (of which only ~$1.5M is deuterium)
       | 
       | I have a few questions and I wonder if any can help:
       | 
       | 1. Is the above fusion fuel correct?
       | 
       | 2. What measures are expected to bring these prices down to price
       | efficiency?
       | 
       | Of course, I am not calculating the cost it would take for the
       | reactor, storage, delivery etc.
       | 
       | Nevertheless, this is an absolutely incredible development and
       | the people working for this progress should be definitely proud
       | of their work. My generation and the ones following will hail
       | this as a breakthrough moment. Thanks!
       | 
       | [1]: https://www.iter.org/sci/FusionFuels
       | 
       | [2]: https://en.wikipedia.org/wiki/Prices_of_chemical_elements
       | 
       | [3]: https://www.science.org/content/article/fusion-power-may-
       | run...
        
         | gene-h wrote:
         | [0] provides economic analysis for this type of power plant.
         | They conclude it would not be unreasonable to get levelized
         | cost of energy could get as low as $25/MWh. For this one really
         | needs a high gain of 1000, although gains of 400 are a bit more
         | reasonable, and a gain of around 100 may be economically
         | competitive in some cases.
         | 
         | While the gain NIF achieved was about 1.5, there is good reason
         | to expect it can be scaled up. Ignition is a runaway process,
         | so small changes in the input can result in large changes in
         | the output. Hydrogen bombs, which also use a burning plasma as
         | was demonstrated here, also suggest that the gain and yield may
         | be scaled up.
         | 
         | [0]https://royalsocietypublishing.org/doi/10.1098/rsta.2020.005
         | ...
        
           | cpleppert wrote:
           | >> Ignition is a runaway process, so small changes in the
           | input can result in large changes in the output. Hydrogen
           | bombs, which also use a burning plasma as was demonstrated
           | here, also suggest that the gain and yield may be scaled up.
           | 
           | Hydrogen bombs are driven by indirect implosion by a nuclear
           | primary. It isn't a runaway process; the yield of a secondary
           | is limited by the implosion achieved by the primary. Most
           | hypothetical designs for an inertial fusion power plant
           | achieve similar energy gains.
        
           | onlyrealcuzzo wrote:
           | I think capital costs & construction times are going to be
           | _extremely_ important.
           | 
           | I think the biggest reason nuclear energy stopped being built
           | is it takes too long to get political wins.
           | 
           | NuScale and other SMNRs might be able to help with that.
           | 
           | However, the capital costs & construction time for Fusion
           | Energy should theoretically be much lower than nuclear
           | reactors.
           | 
           | But are we too far away from it being a reality that anyone
           | is predicting how much?
        
             | gene-h wrote:
             | It will be quite difficult to make fusion cheaper than
             | present day fission. Fusion reactors are new so significant
             | research work will need to be done. There are difficult
             | engineering challenges related to breeding fuel, which
             | involves moving hot, radioactive, and water reactive molten
             | lithium around. Fusion reactors need to be built to high
             | tolerances and will need to be refurbished occasionally due
             | to radiation/heat and in the case of NIF style fusion,
             | explosion damage.
             | 
             | And one still has to deal with many of the same radiation
             | challenges fission plants must deal with. A large quantity
             | or radioactive tritium must be kept on site and neutrons
             | from the fusion reaction will make the reactor radioactive.
             | In fact, fusion produces more neutrons than fission per
             | unit energy. Even so called 'aneutronic' fusion would have
             | side reactions which would produce quite a lot of neutrons.
             | 
             | Fusion is a lot more complicated than using special rocks
             | to boil water.
             | 
             | The main advantage of fusion is a political one. It
             | politically nigh impossible to build a fission reactor in a
             | suburban industrial park, but Commonwealth Fusion Systems
             | is doing exactly that with a fusion reactor[0]. And there
             | is also the slim possibility this type of reactor could
             | explode. Said reactor uses superconducting magnets which
             | store a lot of energy and if something goes wrong, it would
             | be possible for them to release that energy fast.
             | 
             | But, the NRC hasn't made laws for regulating fusion power
             | yet, so they are able to do this.
             | 
             | [0]https://cfs.energy/news-and-media/commonwealth-fusion-
             | system...
        
               | afpx wrote:
               | 50 years from now, are we going to be using fission or
               | fusion?
        
               | gene-h wrote:
               | Hopefully, both. Even if fusion works extremely well,
               | fission should find niches. Fission power is likely to
               | remain more power dense than fusion for a while, so in
               | situations where one cares about weight and size it is
               | better than fusion.
        
             | panick21_ wrote:
             | > However, the capital costs & construction time for Fusion
             | Energy should theoretically be much lower than nuclear
             | reactors.
             | 
             | Maybe then current Gen3+ reactors.
             | 
             | But there is no way they will win economically against
             | GenIV Fission reactors. That are already solving most of
             | the issues with Gen3+ reactors.
             | 
             | They already are much smaller, and therefore much lower
             | CapX. Fuel cost are even cheaper because of better
             | utilization of the fuel. Modern plants operating cost are
             | also less because they are even more automated and need to
             | be refueled less.
             | 
             | There is no practical way fusion can compete in my opinion.
        
           | iamgopal wrote:
           | 1000 time gains is double performance every 2 year, means in
           | 20 year we would be able to achieve fusion with hydrogen from
           | water at home scale min power plants.
        
           | panosfilianos wrote:
           | Thanks a ton for that! $25/MWh is great but not the 10x
           | economic impact I expected. Especially since [1] we see PV at
           | $50/MWh currently.
           | 
           | [1]:
           | https://en.wikipedia.org/wiki/Cost_of_electricity_by_source
        
             | devmor wrote:
             | The economic impact doesn't just come from the fuel to
             | energy ratio. One of the biggest differences is also in the
             | space required. Nuclear fusion reactors could eventually
             | end up being very small - like smaller than an SUV.
             | 
             | Imagine the cost savings in miniaturizing electrical grids.
        
               | panosfilianos wrote:
               | This seems interesting but not especially impactful.
               | 
               | For me, the question here is: can we get our energy to
               | cost 90% less than it did?
               | 
               | Don't get me wrong, I recognise that this is still a huge
               | win (especially environmentally) and that it can have
               | huge runway effects (eg. much more effective
               | decentralization etc.) but it's quite interesting on how
               | we can get these billions of people out of poverty first
               | (or during).
        
               | nebolo wrote:
               | While not 90%, transmission and distribution are around
               | 40% of the cost of retail electricity, so lowering those
               | substantially would go a long way.
        
               | panick21_ wrote:
               | Yeah but are you beating fission, something like:
               | 
               | https://www.moltexflex.com/flex-reactor/
               | 
               | A small fission reactor can do almost everything a fusion
               | reactor can. Fusion fuel is higher density, but fission
               | density is already not an issue.
               | 
               | Fusion still needs to heat water, that's where much of
               | the cost comes from.
        
               | devmor wrote:
               | A small fission reactor is also incredibly dangerous and
               | will always require exotic material.
               | 
               | A fusion reactor does not pose environmental risk and
               | could eventually run on highly available basic elements
               | for everything after the initial "startup" once the
               | technology progresses.
        
               | DesiLurker wrote:
               | if they can be that small then they might find unexpected
               | use in long range spacecrafts or lunar colonies. you'd
               | still have to build and lift the reactor out of earths
               | gravity well.
        
               | devmor wrote:
               | Here on earth we could see them used to power container
               | ships as well, which are some of the biggest contributors
               | to greenhouse emissions as far as vehicles go.
        
         | jboy55 wrote:
         | This isn't for power plants, this is to model the efficiency of
         | the second stage of a stored h-bomb in place of periodically
         | exploding them, which we can't do anymore due to the test-ban
         | treaty.
        
         | pohl wrote:
        
         | JumpCrisscross wrote:
         | > _tritium is ridiculously expensive, at $30k per gram_
         | 
         | D-T fusion almost always breeds tritium in the blanket.
        
           | panosfilianos wrote:
           | Would that mean that you wouldn't need titium to start with?
           | Or that tritium deposits would replenish?
           | 
           | How would it affect the rough calculations above?
        
             | JumpCrisscross wrote:
             | > _Would that mean that you wouldn 't need titium to start
             | with?_
             | 
             | Tritium decays in a decade. To start, you'd need the
             | expensive stuff harvested from the heavy water of spent
             | fuel pools. After that, you'd let your neutrons breed it in
             | lithium (or boron, if you're fancy).
        
               | panosfilianos wrote:
               | So, the approach here would be that it would just be a
               | much more efficient process.
        
             | wernercd wrote:
             | I would also wonder if Titium is that expensive... and it
             | generates titium... would that be part of the "break even"
             | equation? Creating something rare to sell?
        
               | ceejayoz wrote:
               | Current demand is a couple hundred grams per year. We
               | just don't need that much of it. The cost per gram would
               | go down a lot if we needed to mass-produce it.
        
               | panosfilianos wrote:
               | I think what I'm alluding to is, how much can the cost go
               | down. In the case of fossil fuels there value is strongly
               | based on their physical scarcity and cost of
               | extraction/delivery etc.
               | 
               | How much do these things ring true in this case and what
               | are ideas of improvement?
        
               | Kubuxu wrote:
               | It is so rare because tritium is not found in nature in
               | any significant quantity. The amount on the market comes
               | from water recovered from water pools used for spent
               | nuclear material storage.
               | 
               | There also is no enormous market for tritium. So in
               | short, fusion reactors exist on both sides of the tritium
               | market, by becoming the primary producers and consumers
               | of it, which should lead to significant drop in price of
               | tritium.
        
             | creato wrote:
             | Your calculations don't mention energy (J), only power (MW
             | in your post). Fuel supply and cost correlate with energy
             | produced, not power.
             | 
             | Parent post suggests that tritium is a fixed cost, more
             | like a construction cost than a fuel cost. We can't answer
             | this question without a lot more information. We'd need to
             | know how much tritium is needed to reach the point the
             | reactor breeds more than it consumes, if at all.
        
         | trillic wrote:
         | I'd imagine commodity tritium breeders would be a part of the
         | infrastructure build out and that it will be a highly
         | competitive space as fusion-to-the-home nears reality.
        
           | onlyrealcuzzo wrote:
           | What is fusion-to-the-home?
        
             | LegitShady wrote:
             | probably one of those mr fusion units from back to the
             | future.
        
             | aliqot wrote:
             | Power derived from a fusion power plant delivered through
             | conventional powerlines leading to the consumer.
        
       | sbussard wrote:
       | Scientists spend their whole lives researching a particular
       | topic, but as soon as there's a breakthrough the politicians take
       | credit. Unbelievable!!
       | 
       | Excellent milestone for humanity nonetheless
        
       | spencerchubb wrote:
       | The most surprising thing I've learned from this is we're only
       | allocating $624 million / year to this program. We really need
       | better mechanisms for deciding how to allocate taxes.
        
         | jboy55 wrote:
         | Its actually pretty good, since this is primarily weapons
         | testing. The real money is being spent in the EU, where there
         | is at least a chance of getting a sustainable fusion reaction.
        
           | davrosthedalek wrote:
           | It's, depending what calculation you believe, around 20
           | billion for ITER. Started in 2013, first plasma in 2025,
           | first full fusion in 2035. So about a billion per year. Of
           | course, costs are calculated differently, and I'm not sure on
           | what time scale the 600 million are, but it's not that
           | drastically different.
           | 
           | Research wise, it's a pretty big chunk of money. But yeah,
           | more money in research would be nice. (Disclaimer: I am a
           | scientist with grants.)
        
             | jboy55 wrote:
             | Yes, I think more research towards eventual power
             | generation, rather than weapon testing, would be better.
        
             | ZeKK14 wrote:
             | ITER is built in France, but is financed by many countries
             | outside of EU, including the USA. It's not a huge cost per-
             | country.
             | 
             | > the ITER Members China, the European Union, India, Japan,
             | Korea, Russia and the United States
             | 
             | See https://www.iter.org/proj/Countries
        
           | jasonhansel wrote:
           | Not really. IIRC the NIF needs to _pretend_ that it 's about
           | nuclear weapons to secure DoE funding; they (like us) know
           | that it's really about developing fusion as an energy source.
        
             | jboy55 wrote:
             | Or it needs to pretend its about fusion as an energy
             | source, to mask its really about creating and maintaining a
             | stockpile of h-bombs that could destroy every city on
             | earth.
        
         | yrgulation wrote:
         | Would you rather the us takes second place in researching space
         | and energy tech?
        
       | twarge wrote:
       | Remarkable. It's still nuclear energy, and the sobering part for
       | me is that fusion neutrons are an order of magnitude more
       | energetic than fission neutrons. Add the fact that fusion plants
       | are an order of magnitude larger, and you get orders of magnitude
       | more nuclear waste with order of magnitude higher
       | activation/radioactivity.
       | 
       | If you don't like nuclear for these reasons, you'll probably hate
       | fusion.
        
         | fastneutron wrote:
         | Activation products are of a different nature than the fission
         | products and minor actinides you get in fission reactors, and
         | are not necessarily as fearsome to handle, nor is the total
         | activity comparable at all to what you get in spent fuel.
         | 
         | However, those high energy neutrons do a ridiculous amount of
         | damage to the structural materials, and if there are constant
         | outages to swap and repair components, I don't see an easy way
         | of making energy economically.
        
         | floxy wrote:
         | https://en.wikipedia.org/wiki/Aneutronic_fusion
        
         | kahrl wrote:
         | https://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
        
           | twarge wrote:
           | I have a PhD plasma physics, I think I am qualified to make
           | these statements without this sort of dismissal!
        
             | [deleted]
        
             | PaulHoule wrote:
             | It sucks doesn't it!
             | 
             | I met a physicist who had written a paper in the 1980s
             | about a fusion reactor that used the high energy neutrons
             | from D-T fusion to breed 233U from 232Th, around the time
             | that people were losing interest in fast reactors. The
             | reactor itself might not be a profitable source of energy
             | directly, but the fuel it produces would be useful in
             | thermal fission reactors.
             | 
             | Fusion will be attractive as a neutron source long before
             | it is attractive as an energy source, in fact there are
             | many kinds of neutron generators already in use that use
             | fusion.
             | 
             | The waste from fusion will be different in character from
             | fission. Unless you are trying to make TRU you are not
             | going to have any transuranic waste. Most of the real
             | danger from fission products is in isotopes of a few
             | elements in a particular range of atomic number, particular
             | Cs and I.
             | 
             | On the other hand, a D-T reactor is going to have a lot of
             | T around and T is hard to contain since hydrogen likes to
             | infiltrate between the atoms in metals. The flux of
             | neutrons on the first wall is going to be absolutely
             | brutal, how bad the activation is will depend on what exact
             | materials you're using, but the difficulty of the situation
             | is such that you might not have much of a choice.
        
         | blackbear_ wrote:
         | Furthermore, fusion does not produce highly radioactive, long
         | lived nuclear waste. "Fusion produces only low level
         | radioactive waste -- more than fission does -- but this low
         | level waste does not pose any serious danger," said Gonzalez de
         | Vicente. Contaminated items, such as protective clothing,
         | cleaning supplies and even medical tubes or swabs, are short
         | lived, low level radioactive waste that can be safely handled
         | with basic precautions.
         | 
         | From https://www.iaea.org/bulletin/safety-in-fusion
        
           | twarge wrote:
           | Perhaps Dr. dr Vicente is talking about ITER, but surely not
           | a real fusion reactor.
           | 
           | Here's something talking about an actual fusion reactor:
           | 
           | "While the radioactivity level per kilogram of waste would be
           | much smaller than for fission-reactor wastes, the volume and
           | mass of wastes would be many times larger."
           | 
           | and
           | 
           | "To reduce the radiation exposure of plant workers,
           | biological shielding is needed even when the reactor is not
           | operating. In the intensely radioactive environment, remote
           | handling equipment and robots would be required for all
           | maintenance work on reactor components as well as for their
           | replacement because of radiation damage, particle erosion, or
           | melting."
           | 
           | https://thebulletin.org/2017/04/fusion-reactors-not-what-
           | the...
        
       | bookingtrolley6 wrote:
        
       | gabesullice wrote:
       | After the Wright brother's first demonstration of powered flight,
       | I like to imagine all the pessimists in this thread would have
       | said that commercial air transport would never be viable because
       | wood and fabric don't have the material properties to carry a ton
       | of steel.
        
         | jokteur wrote:
         | Yes, try to imagine a London - Tokyo non stop flight in 1902.
         | Would be pretty crazy to imagine, considering that the longest
         | distance the Wright brother flew was 180m.
        
         | kahrl wrote:
         | This is a false equivalence.
        
       | ag315 wrote:
       | Cool technical achievement, but it has essentially no
       | implications for economically or politically significant energy
       | generation anytime soon.
        
       | busyant wrote:
       | I'm sure this has been considered, but I haven't ready anything
       | about the "geo-political" effects of virtually unlimited energy
       | from fusion.
       | 
       | I imagine that power dynamics would change drastically, but I
       | have no clue, really.
       | 
       | I understand that's still far away, but are there any
       | articles/discussions on how large scale fusion-generated energy
       | would change the world?
        
         | josho wrote:
         | Oh it will be interesting. Assuming it is possible to
         | commercialize this at scale then relatively overnight we'll
         | some some of the following:
         | 
         | * The middle-east no longer becomes a strategic region. Wealthy
         | regimes see their income disappear. The US has supported Israel
         | as a strategic check in the region, but with oil losing its
         | value the US no longer needs to fund Israeli security. We are
         | likely to see skirmishes if not major wars, but this time it's
         | over empires in decline, rather than empires with strategic
         | resources.
         | 
         | * Texas' GDP declines substantially creating significant
         | unemployment. Will government scape goat immigration and create
         | further social problems, or invest in leading the transition
         | creating a new wave of energy industries.
         | 
         | * Developing countries swiftly raise their standard of living
         | as cheap energy is brought online. No idea what this
         | ramification would be.
        
       | forthorbor wrote:
        
       | psychoslave wrote:
       | Is that a different approach than the Tokamak, some piece to make
       | it works, or some other relationship? What does it mean for
       | existing projects such as ITER?
       | 
       | https://en.wikipedia.org/wiki/Tokamak
       | 
       | https://en.wikipedia.org/wiki/ITER
        
         | readams wrote:
         | This works in a totally different way, by heating a tiny target
         | fuel pellet with a laser to cause it to collapse and trigger
         | fusion through basically heating and squeezing: more like how a
         | bomb works. It's not easy to see a direct path from this
         | approach to a power plant, but it might involve lining up a
         | steady stream of fuel targets and doing this in a sort of
         | pulsed mode.
         | 
         | Other approaches attempt to create a continuous plasma where
         | fusion can occur confined in a powerful magnetic field, and
         | heated by radio waves to get it going. So there's always fusion
         | happening rather than in short bursts.
        
           | lostmsu wrote:
           | In principle inertial confinement is not much different from
           | internal combustion engines where piston compresses the mix,
           | and the explosion energy is harvested. Here lasers compress
           | the mix, and the explosion energy is not yet harvested (but
           | measured).
           | 
           | Tokamaks (the other approach) are more like jet engines in
           | that they sustain burning. But currently the burning in
           | tokamaks requires more energy than it generates.
        
             | jasonhansel wrote:
             | Could it be argued that we should invest more in ICF and
             | less in tokamaks, given this result? I don't know enough
             | about the field to say.
        
               | lostmsu wrote:
               | I personally believed so since a while ago, for that
               | exact reason. Although I was thinking more of
               | miniaturizing the existing bomb design where fusion
               | material is surrounded by a fission shell made of
               | material with lower critical mass. But I am no expert
               | either.
        
         | blablabla123 wrote:
         | For the Fusion the particles need to get close - but not to
         | close. So the particles in the Tokamak get heated up to reach
         | that. Also it's designed to run continuously but the challenge
         | is the magnetic field so the particles won't hit the wall. (And
         | cool down very quickly)
         | 
         | The Inertia based fusion works by providing the heat/energy
         | with lasers, so the fuel would have to be replaced
         | continuously.
        
       | teeray wrote:
       | Can someone ELI5 why this is significant over previous fusion
       | experiments?
        
         | gjsman-1000 wrote:
         | Previous Fusion experiments, even though we could get Fusion
         | reactions to occur, required more energy to start and sustain
         | the reaction than was generated from it. For the first time,
         | more was generated from the reaction than put in.
        
           | micromacrofoot wrote:
           | Note that while this is important progress, it's a bit of
           | specific accounting. The entire system still requires more
           | energy input than output, but this isolated piece can now
           | output a little more than input.
           | 
           | > This is indeed a promising and exciting result, but we need
           | to remember that this does not take into account the energy
           | required to run the lasers that confine the reaction and
           | other inefficiencies and losses.
           | 
           | https://www.sciencemediacentre.org/expert-reaction-to-
           | fusion...
           | 
           | It's still entirely possible that we will not see a fusion
           | reactor in production within our lifetimes.
        
             | sigmar wrote:
             | Their goal was to produce a fusion reaction not to improve
             | laser efficiency. That's a bit like complaining they didn't
             | account for the energy used to structure the fuel. I don't
             | think it's 'specific accounting' when (output/input)>1 was
             | their goal from the start
        
               | micromacrofoot wrote:
               | The goal in the eyes of the layman is to produce a stable
               | fusion reaction that outputs more than input.
               | 
               | While this is great progress, I feel that it's important
               | to have the full picture. There's a lot of "fusion
               | reaction breakthrough fatigue" stemming from the
               | misunderstanding that fusion power isn't a technology
               | that requires a singular breakthrough.
               | 
               | There are many breakthroughs required to get to fusion
               | powered energy, and this is an important one (worth
               | celebrating) on a long road ahead.
        
               | supergirl wrote:
               | yeah but why is that a worthy goal? does anyone know how
               | to make the lasers 100x more efficient? or did we shift
               | the problem from one impossibility (efficient fusion) to
               | another (efficient lasers)
        
               | govg wrote:
               | Because their mandate is to study a different part of the
               | puzzle from what the laser researchers do. The NIF uses
               | really old laser tech, and in parallel the world has
               | moved onto 20x more efficient lasers. The NIF just wanted
               | to prove they could get a laser (bad one) to hit a pellet
               | and the pellet would send out more energy than the laser
               | put on it. Improving the laser, improving the pellet
               | materials, improving transfer from pellet to usable
               | energy are all different problems being solved by
               | different people.
        
             | prvc wrote:
             | Since there will necessarily be overhead in any kind of
             | finished design, this "threshold" is an arbitrary one to
             | pass, no more significant that 90% or 125%, or any other
             | round number.
        
               | Ancapistani wrote:
               | Sort of.
               | 
               | We don't have a commercially viable technology here yet,
               | but we've proven that it's at least viable for the part
               | that needs to produce energy _actually can_ produce
               | energy.
               | 
               | As I understand it, now we start down the road of
               | improving the ratio and optimizing the process.
               | 
               | FWIW, from my lay perspective it seems like the research
               | NIF is doing is significantly smaller scale than the work
               | being done elsewhere. That's a _good_ thing in this case,
               | because the output:input ration - the Q - seems to
               | increase exponentially relative to input power.
        
               | supergirl wrote:
               | sounds more like someone tells you "hey, I finally found
               | how to do fusion, I just need one more thing, a super
               | efficient laser that no one has built before"
        
         | malfist wrote:
         | No other fusion experiment has achieve greater outputs than
         | inputs.
         | 
         | So this is the first time that a fusion reactor has been net
         | positive for energy production
        
           | leephillips wrote:
           | Neither did this one. This is not a net positive. That's what
           | they told journalists to start the current cycle of hype, but
           | note that announcements direct from DOE don't use that
           | language.
        
       | wnevets wrote:
       | I know this is from the DOE but is this real real or this is
       | wormhole "real"?
        
         | aetherson wrote:
         | It's not like the "wormhole" thing where what was produced
         | isn't really what can plausibly be described as a wormhole. In
         | this case, fusion really did happen, and the amount of energy
         | produced by the fusion reaction was about half again what the
         | energy put into the fusion reaction was.
         | 
         | That said, there are two pretty important caveats about how big
         | a deal it is macroscopically:
         | 
         | 1. In order to have useful fusion power, we'd need at least
         | another order-of-magnitude or so energy out compared to energy
         | in. Maybe, depending on how optimistic you are about the
         | ability to capture that energy and efficiently feed energy in,
         | closer to two orders of magnitude.
         | 
         | 2. This is from an inertial confinement approach to fusion.
         | Unlike the magnetic confinement approaches that we often hear
         | about, this approach doesn't really create a continuously hot,
         | spatially constrained bit of plasma that can then be used to
         | heat things up -- it produces more like a small but intense
         | explosion. There are real doubts about whether you can, even
         | with very favorable energy-out ratios, industrialize that into
         | an actual power plant. It's more challenging to harvest energy
         | from an explosion than it is to harvest energy from a bunch of
         | plasma flowing in a circle.
        
           | wnevets wrote:
           | > 2. This is from an inertial confinement approach to fusion.
           | Unlike the magnetic confinement approaches that we often hear
           | about, this approach doesn't really create a continuously
           | hot, spatially constrained bit of plasma that can then be
           | used to heat things up -- it produces more like a small but
           | intense explosion. There are real doubts about whether you
           | can, even with very favorable energy-out ratios,
           | industrialize that into an actual power plant. It's more
           | challenging to harvest energy from an explosion than it is to
           | harvest energy from a bunch of plasma flowing in a circle.
           | 
           | Thank you, that is the kind of caveat I was expecting.
        
             | lostmsu wrote:
             | > Thank you, that is the kind of caveat I was expecting.
             | 
             | The caveat on caveat is that historically explosions
             | (piston internal combustion engines) were developed before
             | continuous burning (jet turbines).
        
         | leephillips wrote:
         | More real than the wormhole. Real enough to get Chuck Shumer to
         | increase next year's budget, which is why you're hearing about
         | this at all.
        
       | UltraViolence wrote:
       | I thought we had passed this mark a long time ago, but only
       | during short stints.
       | 
       | However, the way they're realizing it by shooting a fuel pellet
       | with lasers is unsustainable and impractical IMHO.
        
         | simiones wrote:
         | If only they were shooting a fuel pellet: they are instead
         | shooting a hohlraum, a precision-engineered piece of gold and
         | that, in turn, shoots the fuel pellet with X-Rays, acting as a
         | kind of aiming/synchronization device. The hohlraum is
         | destroyed in the process, and currently costs millions of
         | dollars to build a new one.
        
           | philipkglass wrote:
           | _The hohlraum is destroyed in the process, and currently
           | costs millions of dollars to build a new one._
           | 
           | Hohlraums are expensive but not millions of dollars. This
           | 2004 report puts the cost at about $2500 each (still far too
           | expensive for a power plant of course) while examining ways
           | to get them under $1 each.
           | 
           | "Cost-Effective Target Fabrication For Inertial Fusion
           | Energy"
           | 
           | https://www.osti.gov/servlets/purl/828518
        
       | bulbosaur123 wrote:
       | TL:DR please, how big of a deal is this and when can we
       | approximately expect cheap or costless energy? And is it sort of
       | like perpetual energy generator? And if yes, doesn't that break
       | law of physics? And if not, why not?
       | 
       | So many questions. Pardon my ignorance.
        
       | mustacheemperor wrote:
       | I don't know about everyone else, but I'm taking this particular
       | moment just to swell with pride and excitement for this
       | achievement by science and forget about the details of how much
       | more needs to be done to create the first power plant. I'm
       | remembering when I first learned about fusion energy development,
       | how distant and unfeasible it seemed, and regardless of how long
       | the road ahead still is it's incredible how far we've come.
       | 
       | Happy Ignition Day everyone. I can hardly believe we really made
       | it here.
        
         | Buttons840 wrote:
         | What about this:
         | https://www.newscientist.com/article/2333346-ignition-confir...
         | 
         | Allegedly ignition was achieved a year ago. How is this
         | different?
        
           | ceejayoz wrote:
           | https://www.nature.com/articles/d41586-022-04440-7
           | 
           | > In August 2021, NIF scientists announced that they had used
           | their high-powered laser device to achieve a record reaction
           | that crossed a critical threshold on the path to ignition,
           | but efforts to replicate that experiment, or shot, in the
           | following months fell short.
           | 
           | Fluke or measurement error, it seems.
        
           | ericmay wrote:
           | A better question to ask yourself is if this isn't any
           | different, why are the entire scientific community, the
           | Lawrence Livermore lab, the DOE, and others so excited about
           | it?
           | 
           | If these are the same thing, why didn't they make a big deal
           | about it before? What's the material difference?
        
             | moloch-hai wrote:
             | The hype machine is fully engaged, and may lead to an
             | influx of budget, something of deadly seriousness to DoE.
             | They have had trouble getting funding increases for this
             | kind of weapons work when it was represented as weapons
             | work. Pretend it's not, and people fall all over themselves
             | to praise it.
             | 
             | But it is weapons work, first, last, and always.
        
           | [deleted]
        
           | jbverschoor wrote:
        
             | ceejayoz wrote:
             | The B-21 isn't unmanned, the nuclear-capable B-2 already
             | existed, and we've had fusion bombs since the 1950s.
        
               | dotnet00 wrote:
               | The B-21 is stated to be capable of uncrewed operation.
        
               | ceejayoz wrote:
               | It's capable of _maybe_ later on being _made_ uncrewed.
               | 
               | https://www.military.com/daily-news/2022/12/03/air-force-
               | rev...
               | 
               | > The service has not fully delivered on, or explained
               | what, that unmanned concept or capability would look
               | like. Defense experts told Military.com prior to the
               | rollout that it is unlikely we'd see a fully autonomous
               | bomber anywhere in the near future.
               | 
               | They also canceled the drone wingman:
               | 
               | > In 2021, Air Force Secretary Frank Kendall publicly
               | discussed the idea of having a drone counterpart to the
               | B-21 that would essentially act as a wingman alongside
               | the bomber. But Kendall later backtracked, telling
               | Breaking Defense in July that the concept was not as
               | "cost-effective" and "less attractive" than previously
               | thought.
        
               | p1esk wrote:
               | I thought they said it could fly unmanned.
        
               | ceejayoz wrote:
               | They've said it might, someday, be modified to do so. The
               | current iteration of it requires a manned crew.
        
             | tmccrary55 wrote:
             | Russia has pretty conclusively shown that they aren't even
             | close to the same league as the US in terms of warfare.
             | 
             | Like comparing an amateur pickup basketball team to the
             | Chicago Bulls.
        
               | maybelsyrup wrote:
               | Uh what US warfare have you been watching? Your analogy
               | only works if it's the like the 2000-200 Bulls (15-67).
        
               | ceejayoz wrote:
               | > Uh what US warfare have you been watching?
               | 
               | Russia is struggling with _Ukraine_ and the NATO weaponry
               | they 've been gifted. 100 mile supply lines proved too
               | much, and they failed entirely to achieve air
               | superiority.
               | 
               | There's zero reason to think they'd do _better_ against
               | the US more directly.
        
               | Firmwarrior wrote:
               | Let's take a step back and remember something: If Russia
               | and the USA had a "war" it would consist of reducing each
               | other to the Stone Age in a couple of hours, then
               | struggling not to starve to death
        
               | mustacheemperor wrote:
               | Let's check our assumptions. The bulletin of atomic
               | scientists first published in 2017 [0] that they felt the
               | modernized US nuclear arsenal is likely sufficient to
               | execute a devastatingly successful first-strike against
               | the Russian arsenal and nuclear command and control,
               | because the new 'super-fuze' in the submarine arsenal
               | significantly upgrades the hard-target kill capability of
               | the warheads. The risk they communicate in this article
               | is that Russia will misinterpret a false positive from
               | their early warning system (which offers only half the
               | warning time of the US') and launch a "retaliatory"
               | strike against the US on a false alarm, because they do
               | not expect to have that capability after a US strike. The
               | modernization program has continued since 2017 and
               | extended to the minuteman arsenal.
               | 
               | [0] https://thebulletin.org/2017/03/how-us-nuclear-force-
               | moderni...
               | 
               | >the United States would be able to target huge portions
               | of its nuclear force against non-hardened targets, the
               | destruction of which would be crucial to a "successful"
               | first strike...The garrisons and their support facilities
               | would probably be destroyed quickly, and some of the
               | dispersed road-mobile launchers would also be quickly
               | destroyed as they were in the process of dispersing. To
               | destroy or expose the remaining launchers...Just 125 US
               | Minuteman III warheads could set fire to some 8,000
               | square miles of forest area where the road-mobile
               | missiles are most likely to be deployed. This would be
               | the equivalent of a circular area with a diameter of 100
               | miles.
               | 
               | >Many of the nearly 300 remaining deployed W76 warheads
               | could be used to attack all command posts associated with
               | Russian ICBMs.
        
               | eitland wrote:
               | Why do you think a country that isn't capable of properly
               | maintaining tanks is capable of maintaining nukes? I
               | mean, ICBMs are literally rocket science with nuclear
               | physics on top of them.
               | 
               | How can a country that cannot even prevent theft of
               | electronics from their "doomsday plane" in front of the
               | 9th of May parade keep a fleet of ICBMs operative?
               | 
               | In a normal year Russia has a total military budget that
               | is smaller than the part of the US military budged
               | allocated to nuke maintenance. How do you think they keep
               | their nukes ready?
               | 
               | All this is before we start talking about corruption.
               | There is a reason why some Russian military leaders have
               | yachts and/or palaces and US military leaders doesn't
               | have them.
               | 
               | In all fairness, maybe most of the yachts are made of
               | missing winter uniforms (I recently saw Russians wearing
               | Tyvek suits as "winter uniforms"). But if they steal so
               | openly from things that was supposed to be used - why
               | wouldn't they steal even more from things that were never
               | meant to be used?
               | 
               | Before I round up, some hearsay: Some journalist that
               | claimed he traveled throught the former Soviet Union
               | shortly after the collapse (I have forgotten the name and
               | I am in no position to verify it anyway) said that he saw
               | missile silos full of rainwater. And when he asked people
               | said it had already been like that for a few years before
               | the collapse in 1991.
               | 
               | Do I think we don't have to care? Absolutely not. They
               | might very well have a few functional nukes, maintained
               | by enthusiastic crews, sailing around on subs somewhere I
               | don't know (I don't follow the space to closely).
               | 
               | But I am not worried that they will send US back to the
               | stone age at all.
        
               | ceejayoz wrote:
               | A nuclear arsenal where only 100 of the 6,000 warheads
               | are actually maintained and functional is still a useful
               | one, though. Less so if 100/6,000 tanks work.
        
               | Firmwarrior wrote:
               | Do you remember when there was a tiny blip in production
               | for COVID, and suddenly the shelves were empty? What do
               | you think is going to happen if 100 nukes go off and wipe
               | out strategic chunks of the USA?
        
               | tmccrary55 wrote:
               | No, not really.
               | 
               | In the Midwest, supply shortages of staples and most
               | consumer goods were not so bad that the "shelves were
               | empty."
               | 
               | You might have had to buy a different brand of a given
               | good.
               | 
               | The only real annoying thing has been products that use
               | semiconductors.
        
               | Firmwarrior wrote:
               | You lads convinced me. Let's have a nuclear war!!
        
               | ceejayoz wrote:
               | The idea that any armed conflict between the two is
               | guaranteed to escalate to nuclear weapons is widespread,
               | but certainly not proven. A US _invasion_ of Russia seems
               | likely to result in nuclear war, but an engagement
               | between conventional forces over a third-party nation
               | like Ukraine seems quite unlikely to. Neither side is
               | suicidal at the leadership level.
               | 
               | US and Russian aviators directly engaged in Vietnam
               | without nuclear holocaust.
        
               | davrosthedalek wrote:
               | I hope you are right, but I am not convinced in Putin's
               | case.
        
               | ceejayoz wrote:
               | If Putin had a big red button that ran wirelessly and
               | automatically, I'd be concerned.
               | 
               | Human beings have to actually implement the order. I
               | think a first-strike order on the US without a serious
               | and _immediate_ existential threat to the Russian state
               | and people winds up with someone offing him with their
               | sidearm.
               | 
               | The Russians have plenty of precedent for this (both
               | offing the leadership, and more generally "oops, he fell
               | out of a window" as a solution), and we've a number of
               | historical examples of lower-level folks going "I don't
               | wanna" in false-alarm situations, like Stanislav Petrov.
        
               | davrosthedalek wrote:
               | I agree, a first strike order is very unlikely. But what
               | if he fires off a nuke over Ukraine? Maybe in a way that
               | it's not 100% clear whether it's a Russian nuke, or a
               | power plant blowing up, or somebody else?
               | 
               | Or he orders to detonate a bomb over the open sea to
               | demonstrate the capability?
               | 
               | But certainly, if I would be Putin, I'd be nervous
               | drinking tea, or walking close to a window. That doesn't
               | make him more stable though.
        
               | ceejayoz wrote:
               | You can't make a nuke look like a power plant explosion;
               | they're simply too different. No nuclear power station
               | can explode in that fashion.
               | 
               | A bomb over the ocean wouldn't demonstrate any new
               | capacity, and would be seen as the bluff it would almost
               | certainly be.
               | 
               | A nuke on Ukranian soil would further open the floodgates
               | of Western aid, expand sanctions, and push more nations
               | firmly into the EU/NATO fold as Finland and Sweden
               | already have been.
        
               | AnimalMuppet wrote:
               | A nuke on Ukrainian soil also has the problem of the
               | prevailing wind direction being from west to east.
               | Detonating a nuke on Ukraine looks a lot like detonating
               | a (smaller) dirty bomb on Russia.
        
               | baseballdork wrote:
               | Probably the warfare that involved invading and occupying
               | 2 states thousands of miles away for 20 years with
               | complete air dominance and suffering under 10,000 KIA.
               | Russia has suffered 20,000 deaths in under a year on its
               | boarder.
        
               | adventured wrote:
               | > Uh what US warfare have you been watching?
               | 
               | The one where the US tends to perform well against its
               | adversaries. True in the Civil War. True in WW1. True in
               | WW2. True in Korea. True in Vietnam. True in the Gulf
               | War. True in Afghanistan. True in Iraq.
               | 
               | And now just a smidgen of its old weapons are helping
               | Ukraine humiliate Russia.
               | 
               | The US was in Afghanistan for two decades with 1,932
               | soldiers killed by hostile action.
               | 
               | Russia lost 15,000+ soldiers in Afghanistan in ten years
               | (probably far higher given the information available and
               | how we've seen Russia lie so dramatically about its
               | losses in Ukraine). It's going to lose 100,000 soldiers
               | in Ukraine in a little over a year.
               | 
               | The US could have held Afghanistan perpetually with
               | 15,000-20,000 soldiers on the ground. The Taliban is a
               | joke of a fighting force, they never competed well with
               | the US; but they have replacement numbers, and guerrilla
               | wars are very time consuming to fight and require massive
               | troop deployments to actually win (you have to suffocate
               | every corner of the enemy presence, like battling an
               | infestation). It wasn't worth it and voters decided that,
               | it had begun to become an unpopular nation building
               | exercise despite the very low losses for the US.
        
               | trhr wrote:
        
               | smegger001 wrote:
               | > True in the Civil War.
               | 
               | >You think so? Ya'll lost 200,000 men to Southern fever,
               | steel, and shot. Next time it'll be 20 million. Know your
               | limits, yankee, and stay north of Dallas.
               | 
               | The south started with a treasonous surprise attack and
               | had most of the the infantry that wasn't stationed in
               | isolated western frontier territory or along the us-
               | canada border, the countries war college at westpoint and
               | many of the countries highest generals, once the north
               | got its act together it started to burn the south to the
               | ground. There is a reason the south still dreads the name
               | Sherman.
               | 
               | You got set on fire once when you started the fight with
               | sucker punch, and you want to try to pick fight again?
        
               | AnimalMuppet wrote:
               | Nit: The south did _not_ start out with West Point. It 's
               | in New York.
        
               | BuckRogers wrote:
               | Well put. For our international observers I would note
               | that the War of Southern Aggression that began with the
               | treasonous attack on Fort Sumter is nearly identical to
               | the behavior we're seeing out of similar origins today.
               | New US states were increasingly free rather than slave
               | states, and thus when democracy wasn't going the way of
               | those who wanted to maintain slavery, they attacked their
               | own government.
               | 
               | The terrorist attack on January 6th was the exact same
               | root cause, democracy not going the way some want it.
               | Leading them to embrace terrorism and violence. After the
               | Civil War, the KKK was created, which continued the
               | terrorism of our citizenry for decades. Yet in that case,
               | the KKK came after the failed attempt at succession,
               | today MAGA came before the attempt.
               | 
               | I describe myself as a 'pre-MAGA Republican who supports
               | labor unions', but there's a rotten seed in American
               | discourse today that was always there and it's largely
               | the same people then as now.
               | 
               | The south would have no chance in Round 2. Most of their
               | money and manpower actually comes from 'Yankees'. Which
               | historically when someone is called that, it's the easy
               | indicator to who is loyal and true to the United States,
               | a real American patriot. Whether spoken spoken by a Brit
               | or Johnny Reb, you definitely want to be called a Yankee
               | as it's a badge of honor that you are loyal to your
               | nation.
               | 
               | Those that are moving south are whose ancestors'
               | allegiance was to the United States of America in the
               | Civil War, and they still maintain that allegiance to
               | this day in those families. They are not loyal to the
               | defunct Confederacy and would not die for their Lost
               | Cause.
        
             | baq wrote:
             | You misspelled 'China'
        
             | Rebelgecko wrote:
             | What unmanned nuclear bomber?
        
               | jbverschoor wrote:
               | The fancy black triangle of like a week ago
        
           | dogma1138 wrote:
           | Because now it's reproducible, controllable and consistently
           | net positive in terms of energy output.
           | 
           | It's not a fluke anymore and I assume the engineering behind
           | this is now understood well enough to develop it further and
           | scale it up.
           | 
           | Fusion for the most part isn't a physics problem it's an
           | engineering problem the difficulty was always in how to
           | implement it in the real world rather than in math at ideal
           | white paper conditions.
        
             | jeffbee wrote:
             | What information available to the public suggests this is
             | reproducible and consistent? They do hundreds of shots
             | every year. Why do we think that this energetic shot wasn't
             | just a result of getting luckier this time than they did a
             | few years ago?
        
               | dogma1138 wrote:
               | Because the press release stated that they've ramped up
               | the reaction and got higher energy output and the scaling
               | wasn't linear in a good way.
        
               | Robotbeat wrote:
               | Because they've been able to do it multiple times, which
               | is better than the zero or one times before.
        
               | civilized wrote:
               | Curious where you found this? I skimmed the press release
               | for a minute and didn't immediately see discussion of the
               | repeatability.
        
               | itishappy wrote:
               | This was the second time. The energy out/in ratio was
               | higher this time, hence the claim of better scaling.
        
         | willis936 wrote:
         | I listened to the two hour press conference. NIF leadership
         | made it clear that energy research is not what Ignition Day is
         | about, why the NIF was made, or why the NIF is operated.
        
         | anon291 wrote:
         | Yeah... this is a great breakthrough and an historic day for
         | physics and engineering and humanity. Every American should
         | swell with pride.
        
         | Balgair wrote:
         | I agree. This is a _Big_ deal. Like, first-lightbulb big, or
         | polio-vaccine big.
         | 
         | My kids are likely to spend the majority of their lives living
         | a world where energy is clean, cheap, and available to
         | everyone. Climate change is something that is not only going to
         | be stopped, but can be reversed for them. Energy grids can be
         | made to be smaller and mutually supporting, lessening the
         | impacts of disasters. Oil dependency and all the political
         | problems that come with it are going to be gone by the time
         | they are grandparents. Nations like Nigeria and East Timor can
         | have power generation like everyone else. The deserts and
         | oceans and tundra of their lives will be places dotted with
         | little greenhouses and fresh vegetables. If they get this down
         | to the size of a car, then everything opens up for travel and
         | recreation. The only real baseline I have to use here is Star
         | Trek.
         | 
         | Of course, there is a long way to go. There is a lot of work
         | and show-stoppers still out there. And the ideas that I see as
         | their future are just _sooooo_ tiny compared to their reality.
         | I 'm thinking of faster horses and they're going to live in a
         | world of supersonic jets. That kind of difference and small
         | thinking of mine.
         | 
         | I'm so happy that, assuming the best with fusion, they are
         | going to live such better lives.
        
           | Mistletoe wrote:
           | This is such a profound and deep misunderstanding of this
           | news story.
        
             | Balgair wrote:
             | how so?
        
           | palata wrote:
           | Let's be honest: the ecological problems we have today (i.e.
           | the fact that we destroyed 2/3 of trees, mammals and insects)
           | has nothing to do with climate change. We did that because we
           | had enough cheap energy to destroy natural habitats.
           | 
           | The consequences of that cheap energy (fossil fuels) is yet
           | to come, that's the climate change problem. And it is big.
           | 
           | Now let's pretend we get fusion to work: maybe (just maybe)
           | that could help the climate change issue (unless it takes
           | decades, in which case its too late), but that won't change
           | the other big problem we have: with cheap energy, we destroy
           | the planet to build malls and swipe TikTok.
           | 
           | We need to re-learn to live with less energy, that's the only
           | way.
        
           | opportune wrote:
           | I agree. I am thinking of my future children or myself into
           | my old age. Even if we don't get commercial fusion until the
           | 2040s, imagine nearly limitless energy (of course we still
           | need to pay for likely massive capex, R&D, and transmission)
           | and its repercussions!
           | 
           | At the very least we can likely pull carbon out of the air
           | faster than we put it in. No more destructive hydropower, no
           | need for fission plants, radically reduced costs for
           | industrial manufacturing. Cheap energy could make raw
           | resource extraction much cheaper and more easily automated.
           | Fast transportation, vertical farming. With the concurrent
           | innovations in battery tech, robotics/automation, and
           | electric vehicles and ships, the future is looking incredibly
           | bright
        
             | vlovich123 wrote:
             | I think you're hand waving too many of the problems away
             | and letting your imagination run way ahead of reality.
             | 
             | > no need for fission plants
             | 
             | Not sure why this is a goal in and of itself. Everything
             | you said is available today with fission and yet still too
             | expensive to remove CO2. Fission has a more real shot at
             | getting to the right price point before fusion even gets
             | off the ground so why not push for more arrows behind
             | something that's likely to help in our lifetime?
        
               | opportune wrote:
               | Energy is an input to basically every single thing we
               | make or do. In economic models it's often been found that
               | "technology" parameters (inversely) correlate almost
               | entirely to energy prices.
               | 
               | If energy cost very little, we could do previously
               | unviable things like vertically farm and let farmland go
               | back to nature, smelt ore onsite, or run
               | simulations/models for a fraction of what they cost now.
        
               | vlovich123 wrote:
               | That's what I'm saying. Why are you assuming that energy
               | costs for fusion would suddenly be lower? These plants
               | take a lot to build and it's not like the primary cost
               | for fission is the fuel. It's the recoupment of massive
               | capex spend, cooling, maintenance, highly trained
               | personnel.
               | 
               | I'm trying to show you that fusion isn't going to
               | magically rain energy mana down on us. It's just fission
               | with less waste (if you discount newer fission designs)
               | except and potentially safer (if you discount newer
               | fission designs) It's likely significantly more expensive
               | given it's a more complicated reactor and we've built 0
               | commercially (and even with this achievement we're not
               | that much closer).
               | 
               | My point is, if you're looking for boundless carbon-free
               | energy, fission reactors already meet all the needs.
               | Additional investments would get reactors that would
               | generate waste competitive with fusion (and in fact can
               | consume all existing generated waste as fuel) and are
               | similarly safe (no runaway reactions).
               | 
               | I would encourage you, if you're serious about carbon-
               | free boundless energy, to devote your advocacy to
               | advancing fission reactors. They're here and there's a
               | straightforward R&D path to get the new reactors
               | (regulatory hurdles are another thing). Fusion reactors
               | won't be here in any reasonable time frame (even if we
               | had a workable design today it would take many decades to
               | build them and then upgrade the grid).
        
           | BoGoToTo wrote:
           | > My kids are likely to spend the majority of their lives
           | living a world where energy is clean, cheap, and available to
           | everyone.
           | 
           | Unless you're in your early teens and don't plan on having
           | kids until you're in your 30's this proba
        
           | smolder wrote:
           | Not that I enjoy being a downer, but I think we're still
           | quite a ways off from a trajectory towards Star Trek society.
           | Clean energy production is absolutely key, with pollution and
           | climate change being big obstacles to a prosperous future,
           | but clean energy doesn't solve all air and water pollution.
           | It won't necessarily scale economically. It also doesn't
           | temper any megalomaniac's pride, to stop them from creating
           | conflict as they try to subjugate everyone else. We live in a
           | very divided, hierarchical world with a fragile order,
           | subject to the whims of people with godlike power over the
           | masses.
           | 
           | One of the most fantastical aspects of Star Trek was the
           | societal evolution into one without interpersonal conflict,
           | the idea being that without scarcity there's no good reason
           | for conflict... I'm just not sure how well that would hold
           | up, knowing people. I don't think all desire for status and
           | power stems from scarcity of resources, and people will
           | continue to lie and do harm to each other as long as they
           | desire power over others.
           | 
           | > My kids are likely to spend the majority of their lives
           | living a world where energy is clean, cheap, and available to
           | everyone.
           | 
           | Being available to everyone does depend on who "everyone" is.
           | If people use the energy to grow food (and more people) until
           | we run into some other population-limiter, we'll always have
           | too many people. Part of achieving sustainability is ending
           | runaway growth. Maybe you can ask people nicely enough to
           | stop reproducing, maybe education will do it, maybe nothing
           | short of force will. Yet our economics were built around
           | continual growth. So, that's all a big problem to solve,
           | still.
        
         | whycome wrote:
         | I guess December 5th was Ignition Day and we didn't know it?
        
           | mixmastamyk wrote:
           | Also Repeal Day for those who want to get lit.
        
         | petilon wrote:
         | When you consider that they laser they used consumed 300
         | megajoules from the wall plug, in order to send 1.8 megajoules
         | to the target, the fact that they got 2.5 megajoules out looks
         | puny in comparison. Even newer lasers only have 20% wall plug
         | efficiency according to the press conference.
         | 
         | So the important point here is, there was no net energy gain.
         | They spent 300 megajoules to get 2.5 out. The scientists only
         | talk about the 1.8 megajoules of laser energy sent to the
         | target, not about the 300 megajoules of electricity needed to
         | send 1.8 megajoules to the target.
        
           | whimsicalism wrote:
           | Energy is conserved in the universe so there is never any net
           | energy gain.
           | 
           | See how pedantic and not helpful that is?
        
             | sweezyjeezy wrote:
             | Power plants add energy to an electrical grid by converting
             | external (chemical/nuclear/kinetic) energy into more
             | electricity than they consume. There's no loss of
             | energy/mass overall, but the amount of available
             | electricity goes up. Since the laser would use electricity
             | from the grid, that should be taken into account.
        
             | OJFord wrote:
             | The point is to get some of it from somewhere cheaper/free
             | - mass, or outside air as in heat pumps.
             | 
             | You can't run your laser on mass or air, if you need a coal
             | firing power plant to run your fusion reactor, from which
             | you get less than you consumed from the coal plant...
             | 
             | It's great progress, it's just not as close to viable as it
             | might sound like - more breakthroughs needed.
        
               | whimsicalism wrote:
               | I have yet to find someone saying it sounds like fusion
               | power reactors are right around the corner, but I have
               | found lots of people shadowboxing these people and
               | attacking the scientists for misleading press releases.
               | 
               | Seems like an overcorrection to something I haven't even
               | seen anyone here say.
        
               | OJFord wrote:
               | I think to a lot of the technically minded, but non
               | nuclear physicists here, it initially sounded like less
               | (paid for/electricity) energy was used than was put out.
               | That's extremely exciting, and the actual news is still
               | fantastic, it's just that 'actually, we needed to pay for
               | over 100x more energy than we counted as the "input"
               | energy [and it's possible to do 10x but not 100x better
               | than that]' is quite a massive caveat on a 3:2 or
               | whatever yield.
               | 
               | I'm not saying they've claimed anything wrong or
               | deliberately misleading, it's just a
               | misunderstanding/misalignment and possibly made worse by
               | the PR teams in the middle.
               | 
               | In other words, I don't think it's an angry 'well
               | actually' type correction so much as it is disappointment
               | - it initially sounded even greater.
        
               | ohyes wrote:
               | Not necessarily, it depends on how the reaction scales.
               | If the reaction does not scale linearly (as is claimed)
               | you don't necessarily have to get more efficient, you
               | just have to up the power until the output curve has
               | increased past the input scaling. How big that is is
               | determined by the efficiency of the input device itself,
               | but it isn't a question of if it will ever happen.
        
               | OJFord wrote:
               | Yes, sure, it's just still a breakthrough or so (or at
               | least _work_ , I don't know how within grasp it is) away
               | from what one may have (as did I) initially assumed.
               | 
               | Tangentially, it does seem fairly intuitive that it
               | should be non-linear in that 'jump start' as it were: a
               | fire can be grown arbitrarily large having started from a
               | single match (or flint or whatever).
        
               | petilon wrote:
               | Right... look at some of the reactions:
               | 
               | "In terms of the physics, we are basically there, and the
               | rest of it, at some level, is _just engineering_ ," he
               | said.
               | 
               | [1] https://www.cbs58.com/news/wisconsin-reacts-to-
               | breakthrough-...
        
             | MichaelZuo wrote:
             | That's a non sequitur. The laser ignition facility is not a
             | smaller version of the entire universe.
        
             | petilon wrote:
             | In nuclear fusion, mass is converted into energy according
             | to the famous equation E = mc^2, where E is energy, m is
             | mass, and c is the speed of light.
        
               | wahern wrote:
               | Mass _is_ energy. Add energy (in any form, such as heat)
               | to a system and you increase its mass. Thus, in the NIF
               | reaction, the mass lost from the pellet is mass imparted
               | on the surrounding environment. Immediately after the
               | fusion reaction, before the energy can dissipate further
               | as heat, etc, the reaction chamber system has the same
               | mass as before the ignition.
               | 
               | There are some nuances regarding the distinction between
               | rest mass vs relativistic mass, but they're not really
               | relevant in this context.
               | 
               | I think what trips people up here is confusing mass with
               | matter. Matter is also subject to mass-energy
               | equivalence, of course, but AFAIU in most common types of
               | nuclear reactions little if any matter, per se, is
               | transformed.
        
               | whimsicalism wrote:
               | Fair enough. To be extra pedantic, mass-energy is
               | conserved in a fixed inertial frame of reference.
        
           | poopbutt7 wrote:
           | You are correct: this is the important point. Until this is
           | actually powering homes at scale and competitive price-
           | which, clearly from these numbers is a fantasy- developments
           | in this field should be dismissed. It's embarrassing to see
           | HN so excited about what's really quite the failure.
           | 
           | (Sent from my ENIAC)
        
             | diordiderot wrote:
             | > ENIAC was the first programmable, electronic, general-
             | purpose digital computer, completed in 1945.
        
           | TeeMassive wrote:
           | As was pointed out in other comments, their lasers and
           | electrical equipment were not efficient as it was not
           | necessary to get the scientific knowledge.
        
             | petilon wrote:
             | In the press conference they mentioned that modern lasers
             | have "20% wall plug efficiency". That means fusion has to
             | generate 5x more energy than this experiment did, for you
             | to get more energy out than you put in.
        
           | snowwrestler wrote:
           | The NIF is not intended to be a power plant, and inertial
           | containment in general is probably not a great design for
           | producing power.
           | 
           | This is scientific breakthrough. The best point of comparison
           | is probably a fusion bomb, which requires an initial fission
           | detonation to create enough pressure and free neutrons to
           | force a net-positive fusion reaction. But at the NIF they do
           | it using only lasers... incredible.
        
           | jononomo wrote:
           | Also, they're not counting all the meals the scientists ate
           | --- this is total BS.
        
       | _a_a_a_ wrote:
       | Maybe I missed it but it's not a net positive output. From the
       | article, the implication it is:
       | 
       | "LLNL's experiment surpassed the fusion threshold by delivering
       | 2.05 megajoules (MJ) of energy to the target, resulting in 3.15
       | MJ of fusion energy output"
       | 
       | From newscientist, the same info followed by a rider:
       | 
       | "generated a power output of 3.15 megajoules from a laser power
       | output of 2.05 megajoules - a gain of around 150 per cent.
       | However, this is far outweighed by the roughly 300 megajoules
       | drawn from the electrical grid to power the lasers in the first
       | place"
        
         | belval wrote:
         | This was explained by another commenter yesterday, but this is
         | not an issue. The 3.15:2.05 ratio is the news as it is the part
         | that was difficult to achieve. The 300MJ accounts for
         | significant laser inefficiencies in much the same way that the
         | 3.15MJ of output won't convert to 3.15MJ of electricity as the
         | conversion is not loss less.
         | 
         | In other words: it's a net-positive output for that reaction,
         | not the whole process, there is still a lot of work to be done
         | before you and I exchange comments on a server powered by
         | fusion energy in homes powered by fusion energy.
        
           | _a_a_a_ wrote:
           | Granted...
           | 
           | > in much the same way that the 3.15MJ of output won't
           | convert to 3.15MJ of electricity as the conversion is not
           | loss less
           | 
           | ...and very much touche! That's a good point. But I do feel
           | the overall loss should have been made clear and distinct
           | from the gain in one part of the whole. Gross vs net perhaps?
        
             | jasonhansel wrote:
             | IIRC part of the issue is that NIF's lasers are very old
             | and much less efficient than more modern ones. So the 300
             | MJ needed to power the lasers is higher than would be
             | expected if this were commercialized.
        
       | empiricus wrote:
       | I still don't understand why we waste time and money with fusion.
       | Fision so much easier. Should focus on it. Fusion is ok, but 100
       | years into the future when we are bored.
        
         | XCSme wrote:
         | ChatGPT can answer this:
         | 
         | > Fission is currently the most common method of generating
         | nuclear power, and it has been used in power plants for many
         | years. It is a relatively well-understood technology and it can
         | provide a large amount of energy with relatively little fuel.
         | However, fission produces radioactive waste and the risk of
         | accidents, such as the one that occurred at the Fukushima
         | nuclear power plant in Japan in 2011.
         | 
         | > In contrast, fusion has the potential to provide even more
         | energy than fission and it produces very little radioactive
         | waste. It is considered a safer and more sustainable source of
         | energy than fission.
        
         | empiricus wrote:
         | Actually just a rhetorical question. We are so irational that
         | fusion makes perfect sense.
        
       | gfodor wrote:
       | Another good time to remind everyone that the inventor of the
       | maser (which led to the laser), Charles Townes, was discouraged
       | by his department chair (allegedly): "Look, you should stop the
       | work you are doing. It isn't going to work. You know it's not
       | going to work, we know it's not going to work. You're wasting
       | money, Just stop!" A few months later, it worked. [1]
       | 
       | [1]
       | https://www.theregister.com/2015/01/29/charles_townes_nobel_...
        
         | quickthrower2 wrote:
         | > He later explained that he was able to refuse to stop his
         | research because he had tenure, so there was nothing they could
         | really do to stop him.
         | 
         | Not having to chase your next meal can make a big difference
        
           | doikor wrote:
           | This is why tenure for fundamental research is very
           | important. You have to be free to fail without consequences
           | or you won't be able to take the risks to figure this stuff
           | out.
        
           | chaosbolt wrote:
           | Exactly, this is the biggest problem with modern
           | universities.
           | 
           | I wish billionaires would fund things like this directly as
           | in no patent no nothing, just from the goodness of their
           | hearts, which they claim is there seeing how much they all
           | pledge to charities... But the reality is different, Oxford
           | pledged to donate the rights to their covid vaccine for free
           | then was urged by the bill & melinda "foundation" to reverse
           | course and sold it to pharma companies.
        
         | nielsbot wrote:
         | "If we'd known it was impossible, we never would have
         | succeeded!"
        
       | sam0x17 wrote:
       | Early in my career I had the pleasure of interning at LLNL
       | (ironically, working on a completely open source compiler
       | project) but I was able to go on a number of tours of NIF. It was
       | extremely cool. They have a whole team of software engineers
       | writing software just to keep all the mirrors calibrated and
       | things like that. In person it is much bigger than it seems in
       | pictures.
        
       | dsign wrote:
       | HN people has three orders of magnitude more technical background
       | and education than politicians, yet when it's about fusion,
       | fision, renewables and climate warming, we only manage to output
       | a miserable 0.01 % consensus and the rest dissipates in waste
       | argument.
       | 
       | It comes to reason, the politicians are going to produce only
       | 0.00001% of consensus.
       | 
       | Conclusion: things are looking rather bad. We are not going to
       | achieve Civilization Survival, much less Singularity Ignition.
       | 
       | My suggestion: highly educated Homo Sapiens may not be the right
       | course. There is a proven way of saving the planet which, by
       | virtue of its remarkably sustainable intellect, we should be
       | investing more on: koalas.
        
         | xiphias2 wrote:
         | Maybe if the article would contain the HN names of the
         | scientists in the experiment in bold instead of Senator names,
         | it would be easier to find them (I'm sure some of them are
         | around here). We should just find those sources, it's not that
         | hard in the internet age.
        
         | quickthrower2 wrote:
         | HN comments is an exploration of the topic. There is no stated
         | goal to reach consensus. Also there is no requirement to be
         | deeply knowledgeable about physics, energy or fusion to
         | comment.
        
         | mclightning wrote:
         | I have been a HN user for a long time. Honestly, I disagree.
         | Most HN users commenting here with smart stuff about fusion,
         | just read it on another page a day or a week ago, from a bite-
         | sized article or a reddit comment. Everyone, for the most part,
         | parroting what they read on a short note somewhere else. Some
         | more committed ones read the synopsis of a few papers before
         | writing something smart.
         | 
         | Anything you read on the internet, explaining any advanced
         | scientific concepts like fusion etc... take it with a huge
         | grain of salt.
         | 
         | We are all parrots.
        
           | willis936 wrote:
           | Some commenters have devoted their career to it.
        
             | mclightning wrote:
             | They're a tiny tiny minority if any, compared to what we
             | are seeing here in comments.
             | 
             | I'm sure they would agree with what I said when they scroll
             | through the comments.
             | 
             | I would not want to wander into HN comments section if I am
             | doing any kind of divergent innovation, challenging the
             | limits of what's technically possible. People here just
             | parrot the status-quo as the absolute truth. If that was
             | the case, humanity would have made zero progress.
             | 
             | Some nerd in some quiet corner, working hard in disbelief
             | of the rest of the society, is the one changing the course
             | of history. Not the ones, parroting established textual
             | truths. There is GPT-3 for that.
        
         | pontifier wrote:
         | It doesn't matter if people agree, it only matters if it works
         | or not.
        
       | jmyeet wrote:
       | I hope commercial fusion power generation becomes a reality but
       | I'm far from convinced that's the case. What we see here is just
       | solving one problem with many more to go.
       | 
       | Energy output exceeding energy input produces a surplus of
       | energy. That's a must and that's the breakthrough LLNL is
       | announcing but le tme list the some of the known barriers to
       | producing electricity:
       | 
       | 1. How stable is the reaction? What failure modes does it have?
       | While fusion doesn't have the same failure modes as fission does
       | (eg Chernobyl) it could still result in significant damage to the
       | container or even the facility;
       | 
       | 2. What's the relationship between capex ("capital expendiutre"),
       | lifetime, maintenance and power generation. An extreme example is
       | if your power plant costs $50B with annual mainteance of $2B and
       | a life of 30 years but only produces 100MW of power then even
       | though the fuel is free it's not economical because those capex
       | and operational costs have to be amortized over the life of the
       | plant;
       | 
       | 3. How available are the fuels? Of course hydrogen is abundant
       | but most of it is protium (H1), which is not useful for current
       | fusion research. Most of it is DT fusion, meaning deuterium (H2)
       | - tritium (H3). Deuterium is naturally occuring (IIRC ~1ppm).
       | Tritium is not. It needs to be bred.
       | 
       | 4. What about neutrons? Neutrons create two problems. The first
       | is energy loss. High speed neutrons are energy loss from your
       | system. Inertial confinement (ie this result) tries to capture
       | neutrons with a "shell". Older designs (eg ITER) use a tokamak,
       | which is magnetic containment of a superheated plasma. Magnetic
       | fields are great for containing electrons and hydrogen nucei
       | because they're positively charged. Neutrons obviously have no
       | electric charge so just escape. The second problem is the damage
       | these neutrons cause (ie "neutron embrittlement").
       | 
       | 5. How do you convert that energy into power? Nuclear fission,
       | for example, heats water into steam that turns a turbine that
       | generates electricity. This isn't particularly efficient and
       | greatly adds to the costs. It's another system that needs to be
       | maintained. "Direct energy conversion" would be the holy grail
       | here but that's all very theoretical at this point.
       | 
       | Once you start adding up efficiencies in the different stages of
       | electricity generation you have to do significanlty better than
       | simply exceeding power input.
       | 
       | It's a notable achievement but as the release says, viable power
       | generation is still a long way away (ie decades).
        
         | pelorat wrote:
         | This experiment was never intended to/or form the basis of a
         | nuclear fusion reactor.
        
       | typon wrote:
       | This makes me feel America is back. This is a big achievement and
       | should not be underplayed whatsoever. Whichever country achieves
       | practical fusion is going to be dominant in the next century.
        
         | drumhead wrote:
         | America never went away. The major scientific and tecnological
         | achievements of the the last 30 years are virtually all
         | American.
        
         | padjo wrote:
         | I'm pretty sure this heavily politicised press release is
         | designed to make you think America is back.
        
       | SkyMarshal wrote:
       | It's interesting that they beat ITER to ignition. I wonder if
       | this changes the direction of fusion research and funding in any
       | way.
        
       | supergirl wrote:
       | everyone should watch https://www.youtube.com/watch?v=LJ4W1g-6JiY
       | to put this into perspective.
       | 
       | for some reason, all the news articles are extremely misleading.
       | 
       | previous output ratio for this fusion method was something like
       | 70%, now it is 150%. it's a useful improvement, but not a major
       | breakthrough. the whole system still consumes 100x more energy
       | than it produces. 100MJ of energy is needed to power the laser.
       | the laser generates only 2MJ of energy that powers fusion. fusion
       | generates 3MJ of output energy. so all the articles are saying
       | "they put 2MJ energy and got 3MJ energy back". no, they put 102MJ
       | and got 3MJ.
        
         | DesiLurker wrote:
         | as somebody already explained to you earlier, the NIF uses
         | arcane lasers because their focus is not lasers at the moment,
         | it is fusion. At current tech level we have about 20% laser
         | efficiency (with some types as much as 50%, not sure if they
         | apply). this experiment specifically was about energy positive
         | from a fusion reaction which has never been done except for
         | uncontrolled things like hydrogen bombs. as far as a fusion
         | milestone goes, this is a big deal.
         | 
         | Also, the other thing most commenters are missing here is the
         | remaining problems are incrementally solvable so we should see
         | steady improvements in laser efficiency and pellet optimization
         | going forward. this is even doable with VC money (which we have
         | some now but not significant). in that sense it is a pretty
         | decent development.
        
       | jerrygoyal wrote:
       | remember those "experts" who said fusion won't be feasible before
       | second-half of this century?
        
       | maerF0x0 wrote:
       | > "We have had a theoretical understanding of fusion for over a
       | century, but the journey from knowing to doing can be long and
       | arduous. Today's milestone shows what we can do with
       | perseverance," said Dr. Arati Prabhakar, the President's Chief
       | Advisor for Science and Technology and Director of the White
       | House Office of Science and Technology Policy.
       | 
       | This part gives me so much hope as we have understandings of what
       | is theoretically possible, and in due time humanity reaches them.
       | This gives me a lot of hope especially in the fields of curing
       | major diseases and in longevity!
        
       | logical_ferry wrote:
       | On a scale of 1 to invention of
       | fire/wheel/smelting/electricity/computers, how relevant is this?
       | I have trouble comprehending the historical impact.
        
         | lostmsu wrote:
         | It is less of inventing and more of engineering. But I would
         | put it along with ARPANET.
        
         | low_tech_punk wrote:
         | wright brothers first flight?
        
       | snshn wrote:
       | I like how over 60 years after the nuclear boom, it somehow just
       | happened to happen today. Just when the world is ready to
       | transition to electric vehicles on a global scale, just when oil
       | companies aren't able to make as much money from oil as they used
       | to, just when one of the major suppliers of fossil fuels (Russia)
       | is at war with the West, it has somehow magically happened. What
       | a coinky-dink.
       | 
       | Throw lots of money at something when you need it to happen and
       | then it will happen. Or have control over the technology and
       | don't let it see the light of day until it benefits you
       | financially and makes your enemies lose their main stream of
       | income. I truly applaud this timing and will err on the side of
       | conspiracy rather than coincidence reading more about this
       | "breakthrough".
        
         | Apocryphon wrote:
         | Is that you, Lyndon?
        
           | PaulHoule wrote:
           | Lyndon Larouche came to my high school (in New Hampshire) for
           | the presidential primaries in 1988 and talked about
           | antimatter as an energy source.
           | 
           | Years later I saw a picture of an Iranian woman holding a
           | sign that said "Nuclear Power is a Human Right" and
           | thought... She much be a LaRouchite.
           | 
           | I wound up voting for Diane Sare, another LaRouchite, for US
           | Senate in New York this year even though I know they're a
           | coercive organization like the Scientologists or the
           | Longtermists and I disagreed with her position on Ukraine --
           | we had a really sad ballot this year since they made it much
           | harder for 3rd party candidates to get one and she was the
           | only one.
           | 
           | LaRouchites are the only people left who want to stamp out
           | the Beatles but they are required to not only listen to only
           | classical music but are only allowed to listen to Brahms and
           | anything older. If I ran into a LaRouchite and wanted to make
           | them squirm I would talk to them about Debussy.
        
         | Alifatisk wrote:
         | You're right when I think about it, the timing is amazing
        
         | LarryMullins wrote:
         | > _I like how over 60 years after the nuclear boom, it somehow
         | just happened to happen today. Just when the world is ready to
         | transition to electric vehicles on a global scale, just when
         | oil companies aren 't able to make as much money from oil as
         | they used to, just when one of the major suppliers of fossil
         | fuels (Russia) is at war with the West, it has somehow
         | magically happened. What a coinky-dink._
         | 
         | It would be coincidental timing, if the most breathless
         | headlines were actually true. But in reality we're still
         | decades away from commercially viable fusion power generation.
         | A fusion energy gain factor of Q=1 is little more than a
         | psychological hurdle. Imagine you have a process that consumes
         | 1 gigawatt of power and produces 1 gigawatt + one additional
         | watt of power; that's Q=1. And it's certainly not commercially
         | viable.
        
       | johnlk wrote:
       | "...a game-changer for efforts to achieve President Biden's goal
       | of a net-zero carbon economy".
       | 
       | That's the best outcome you can think of as a result of possible
       | free energy?
        
         | seanw444 wrote:
         | Thank you, Saint Biden, for doing the bare minimum for the
         | ability to slap your name on it.
        
         | typeofhuman wrote:
         | 10% for the Big Guy.
        
       | randomsearch wrote:
       | This is a really hard question to answer, but do you think in
       | peacetime 1930s if you'd asked someone how long it would take to
       | build the bomb, they'd say "we're only a few decades away with
       | proper funding"?
       | 
       | The pay off achieved by accelerating fusion development seems to
       | justify almost any amount of spending. Is it worth going for it?
       | 
       | The most important subquestion for me: is there a sufficiently
       | brilliant living scientist who has the technical ability,
       | managerial skills, and integrity to be trusted to deliver? I
       | wonder if this is the reason we haven't already done it.
        
         | sergiomattei wrote:
         | Science is a collaborative achievement. There isn't one
         | scientist that can deliver at this scale and complexity.
        
           | randomsearch wrote:
           | Oppenheimer
        
       | endisneigh wrote:
       | I'd love to hear the pros and cons of fusion vs micro molten salt
       | fission reactors.
        
         | loeg wrote:
         | Both are decades away from being viable power plant technology,
         | which is either a con or a pro depending on your point of view.
        
         | thehappypm wrote:
         | Fission requires material that can be used in nuclear weapons.
         | 
         | Fission can always melt down.
        
       | tibbydudeza wrote:
       | Congrats Doc Ok.
        
       | tommica wrote:
       | Gratz to the scientists, seems like an impressive achievement!
        
       | kobalsky wrote:
       | ELI5 level question.
       | 
       | Please correct me if I'm saying something stupid.
       | 
       | If you toss a solar mass of water into the sun it just becomes
       | fuel.
       | 
       | So, could a fusion reactor, when efficiency is improved, use
       | water as fuel?
        
         | ArtificialAI wrote:
         | Yes, that's generally correct. If you were to toss a solar mass
         | of water into the sun, it would become fuel for the sun's
         | fusion reactions. Fusion reactors work in a similar way, but on
         | a much smaller scale. They use fuel, typically hydrogen or a
         | mixture of hydrogen and helium, and use intense heat and
         | pressure to fuse the atoms together, releasing a large amount
         | of energy in the process.
        
       | yuvalkarmi wrote:
       | Tangential, but fun: the following is NOT what this post says.
       | The following is the response to a the ChatGPT prompt "write the
       | press release by an imagined body called the Department of Energy
       | announcing the achievement of fusion ignition." Mind you, ChatGPT
       | training data ends in 2021, so it's definitely not aware of this
       | news:
       | 
       | "The Department of Energy is pleased to announce the successful
       | achievement of fusion ignition in our latest experiment. This
       | breakthrough marks a major milestone in our pursuit of clean,
       | limitless energy.
       | 
       | Fusion, the process by which atomic nuclei combine to release
       | vast amounts of energy, has long been considered the Holy Grail
       | of energy production. It has the potential to provide an
       | virtually limitless supply of clean, safe energy, without the
       | harmful greenhouse gas emissions or dangerous waste products of
       | other forms of energy production.
       | 
       | For decades, scientists and engineers have been working to unlock
       | the secrets of fusion and harness its power. This has been a
       | challenging and complex endeavor, but we are now closer than ever
       | to achieving our goal. The successful fusion ignition in our
       | experiment marks the first time that this process has been
       | achieved outside of the core of a star. This is a significant
       | step forward in our efforts to harness the power of fusion and
       | bring it to practical use.
       | 
       | We believe that fusion has the potential to revolutionize the way
       | we produce energy, and we are committed to pursuing this
       | technology with all of the resources at our disposal. In the
       | coming years, we will continue to conduct experiments and
       | research, with the goal of developing a fusion reactor that can
       | provide a stable, reliable source of energy.
       | 
       | We are extremely proud of this achievement, and we will continue
       | to work tirelessly to develop this technology and bring it to the
       | world. This is an exciting time for energy production, and we are
       | confident that fusion will play a major role in our collective
       | future. We are grateful for the support of our colleagues and
       | partners in this effort, and we look forward to continuing to
       | push the boundaries of what is possible."
        
       | lukeplato wrote:
       | What does this mean for ITER and magnetic confinement fusion?
        
       | Palpatineli wrote:
       | Calling this fusion ignition is stupid. Laser fusion is unlike
       | other fusion devices in that the efficiency of laser is extremely
       | low. It is true that the reaction created 3MJ when the laser
       | energy input INTO THE REACTION CHAMBER is 2MJ. But the whole
       | laser system took 300MJ to run for this one shot. Thus the real Q
       | value is extremely low compared to other fusion methods.
        
         | pmarreck wrote:
         | I'm not sure I understand your criticism
        
         | leephillips wrote:
         | Note that the announcements refer to laser energy supplied to
         | the target, not laser energy entering the chamber. The former
         | is a fraction of the latter, and the basis for the term
         | "scientific gain". The actual target gain may be < 1.
        
       | devmor wrote:
       | This is some of the most incredible and inspiring scientific news
       | in my lifetime. I am overcome with excitement right now.
        
       | cm2187 wrote:
       | It's a weird scientific annoncement, punctuated with quotes from
       | politicians...
        
       | pontifier wrote:
       | Inertial Fusion in a Magnetic field is something I've been
       | pushing for a long time. There are a lot of interesting
       | variations on this design, and I hope I can get more interest in
       | my design at http://www.DDproFusion.com
        
       | bioemerl wrote:
       | Here's your most exciting paragraph
       | 
       | > LLNL's experiment surpassed the fusion threshold by delivering
       | 2.05 megajoules (MJ) of energy to the target, resulting in 3.15
       | MJ of fusion energy output, demonstrating for the first time a
       | most fundamental science basis for inertial fusion energy (IFE).
       | Many advanced science and technology developments are still
       | needed to achieve simple, affordable IFE to power homes and
       | businesses, and DOE is currently restarting a broad-based,
       | coordinated IFE program in the United States. Combined with
       | private-sector investment, there is a lot of momentum to drive
       | rapid progress toward fusion commercialization.
       | 
       | It's fusion Manhattan project time.
        
         | jpeter wrote:
         | Imagine if Musk spend 44 Billion fusion
        
           | adventured wrote:
           | Given it's Musk and his stated primary life goal, the most
           | ridiculous aspect of the Twitter debacle for him, is: not
           | only of course did he overpay for Twitter by at least 2x; not
           | only is his net worth going to contract as Tesla's stock
           | compresses (such that the poor Twitter decision is going to
           | be that much more painful in relation to his overall wealth);
           | but the $40x billion could have probably paid for getting
           | Starship to Mars. He's not going to be as rich in the future
           | as he was in that moment, and he'll be relentlessly mocked
           | for the context as his ship takes on water (eg when he's
           | worth $60-$80 billion and spent $44 billion buying Twitter
           | and SpaceX needs $10+ billion infused into it to keep
           | pursuing Mars).
        
             | yreg wrote:
             | He didn't pay 44B. 13B are bank loans (that need to be paid
             | back by Twitter, not Elon). For the other 31B he had some
             | co-investors as well.
             | 
             | But yes, it was clearly a mistake.
        
             | p_j_w wrote:
             | >the $40x billion could have probably paid for getting
             | Starship to Mars.
             | 
             | Maybe he doesn't actually believe in Starship.
        
               | panick21_ wrote:
               | Or maybe he expected Twitter to actually make money, or
               | at least not lose money.
               | 
               | And this could still be true.
               | 
               | People here act like he bought Twitter and then deleted
               | the website. This isn't the case.
               | 
               | Did he overpay, yes, but its still a business that is
               | worth something.
        
               | TMWNN wrote:
               | >People here act like he bought Twitter and then deleted
               | the website. This isn't the case.
               | 
               | I was told that Twitter would collapse and die any day
               | now a month ago.
               | 
               | It seems to be holding up well enough during the current
               | mega world event known as the FIFA World Cup.
        
               | zizee wrote:
               | Are you suggesting it's all an elaborate scheme?
               | 
               | I know it is popular/easy to hate on the man right now,
               | but this is a really strange take.
               | 
               | Given that Musk has been talking about mars since at
               | least 2001, many years before he had the resources he has
               | now, and almost went bankrupt funding spacex's first
               | orbital rocket, it's hard to believe he's pretending.
               | 
               | People seem happy to believe all negative things they
               | hear about him, but discount anything that doesn't gel
               | with this negative image. It's like how the same people
               | who put all missteps of Tesla/SpaceX at Elons feet, will
               | also discount any of the successes and say he has nothing
               | to do with them.
        
               | asdff wrote:
               | The boring company was literally an elaborate scheme on
               | the other hand. Fool me once, shame on you. Fool me, you
               | can't get fooled again.
        
               | fastball wrote:
               | I dunno, if you look at the Boring Company through the
               | lens of "this man really wants to go to Mars", it kinda
               | makes sense. Probably a lot of Mars colony infrastructure
               | should be tunneled underground, given the lack of
               | atmosphere / magnetosphere.
               | 
               | Things like Hyperloop also make more sense in that
               | context.
        
               | adventured wrote:
               | It appears to be working/progressing properly so far (and
               | quite rapidly compared to norms in the industry),
               | including the Raptor engines. I doubt that's it.
               | 
               | Musk has very obviously poor impulse control. Someone
               | more contained, patient, less impulsive, would have
               | waited and taken a more strategic approach to acquiring
               | Twitter (which would have left an opening to let the
               | stock implode with the rest of the tech market, after
               | which one could have pounced and grabbed it for far
               | cheaper). On the flip side, that less impulsive person
               | probably wouldn't have started SpaceX in the first place
               | (given the suicidal fiscal task involved and context at
               | the time in the industry), or wouldn't have gone to the
               | financial extremes required to make it succeed (betting
               | essentially all of his wealth on Tesla and SpaceX).
        
           | DesiLurker wrote:
           | Imagine if we've spent 10% of the current military budget
           | ($600B+) on renewables & fusion. We wouldn't have to fight
           | those wars for resources.
        
             | lossolo wrote:
             | > We wouldn't have to fight those wars for resources.
             | 
             | You mean wars for oil? Fusion would not solve that, that
             | wars were not about energy per se but about control and
             | domination, keeping USD as world reserve currency and US as
             | world hegemon. Look at Taiwan and chips situation, no oil
             | there, there will be always some "oil" out there that you
             | will want to control instead of giving that control to your
             | rivals. It's game theory 101.
        
               | DesiLurker wrote:
               | okay but oil is a fundamental input into everything hence
               | a much bigger threat than say TSMC's nextgen fab.
               | everybody understands that with some effort those outputs
               | of a strong economy can be recreated but not inputs.
               | Arguably lithium or water may become that but we are
               | currently far from it. Sure there will always be
               | something we'd want to control but we can go in more
               | calm, clearheaded way towards it rather than just use
               | force because we have the biggest stick.
               | 
               | people love to invoke game theory but fail to explain why
               | only we spend more than next 10 countries military budget
               | _combined_. plus its quite unclear what we get out of it
               | because of all the secrecy  & likely its mostly inflated
               | costs and kickbacks. The wars in Iraq/Afghanistan
               | themselves have cost close to 3T over time & thats
               | outside of annual budgets. Personally I'd have preferred
               | to take medicare for all for that amount of money.
        
               | lossolo wrote:
               | > Sure there will always be something we'd want to
               | control but we can go in more calm, clearheaded way
               | towards it rather than just use force because we have the
               | biggest stick.
               | 
               | Unfortunately no, you can't go more calm because
               | projection of force is what keeps status quo and your
               | rivals in place, not liberal values or clearheaded minds.
               | There is no world police, the one with the biggest stick
               | makes the rules. US is not the first hegemon in history
               | of the world, we had Roman Empire, we had Dutch Empire
               | etc, all of the world hegemons were major military
               | powers. There is always some challenger waiting in the
               | shadows to take over your position, you can't just sit
               | and be calm because you will lose what you have, I assure
               | you that others will not just sit calm but claim what's
               | yours if they see sign of weakness, history proves that
               | again and again.
               | 
               | > but fail to explain why only we spend more than next 10
               | countries military budget combined
               | 
               | Well it's easy to explain, US have it in its doctrine
               | that it needs to have military strong enough to fight 2
               | wars at a time so it needs to spend more than at least a
               | few countries behind it but a lot of this budget is
               | probably not spent well. The problem here is that when
               | you stop being world hegemon with the biggest stick, your
               | currency stops being world reserve currency which means
               | you can't finance your debt the same way as before, which
               | has drastic consequences to your budget and it would be
               | really fatal for US. Sometimes you just can't stop the
               | music even when you don't like the melody because silence
               | will hurt you.
               | 
               | > plus its quite unclear what we get out of it because of
               | all the secrecy & likely its mostly inflated costs and
               | kickbacks.
               | 
               | Agreed that's inefficient, you probably could achieve the
               | same with lower costs but how much lower I don't know if
               | anyone knows.
        
           | [deleted]
        
         | simiones wrote:
         | That's a very apt analogy, as both this and Manhattan are
         | weapons research programs.
         | 
         | I'm not very excited in hearing we'll get even more powerful
         | thermo-nuclear bombs.
        
           | ceejayoz wrote:
           | Do more powerful bombs really make any difference? Seems a
           | bit like worrying about the impact of climate-driven ocean
           | rise on the pressure at the bottom of the Marianas Trench.
        
           | jerf wrote:
           | Fusion bombs have existed since the early 1950s. Technology
           | rapidly developed to the point that they can essentially be
           | built to be arbitrarily large, far beyond any practical war
           | purpose. There is no need for any larger bomb than what was
           | built many decades ago. None of this research is necessary
           | for bombs. All of the difficult problems fusion power
           | generation faces with long-term plasma confinement go away
           | when you're just trying to squeeze as hard as you can and are
           | willing to use fission bombs to do it in an otherwise
           | uncontrolled manner.
        
             | jboy55 wrote:
             | It is necessary since they banned the testing of nuclear
             | weapons. Before they would do this kind of research by
             | imploding a cylinder of uranium encasing a hydrogen core
             | with X-rays produced by a "Fat Man" style bomb. Now they
             | implode a cylindrical casing full of hydrogen by x-rays
             | caused by a laser vaporizing an outer layer.
             | 
             | "It's a big milestone, but NIF is not a fusion-energy
             | device," says Dave Hammer, a nuclear engineer at Cornell
             | University in Ithaca, New York.
             | 
             | Herrmann acknowledges as much, saying that there are many
             | steps on the path to laser fusion energy. "NIF was not
             | designed to be efficient," he says. "It was designed to be
             | the biggest laser we could possibly build to give us the
             | data we need for the [nuclear] stockpile research
             | programme."
             | 
             | https://www.nature.com/articles/d41586-022-04440-7
        
             | exmadscientist wrote:
             | > None of this research is necessary for bombs.
             | 
             | And yet that's exactly why the NIF was actually built. They
             | do plenty of weapons research:
             | https://wci.llnl.gov/facilities/nif I'm told the building
             | was even built to switch over between civilian and
             | classified use unusually quickly, but I'm having trouble
             | turning up a citation for that right now with just my phone
             | and 2022-Google.
             | 
             | > All of the difficult problems fusion power generation
             | faces with long-term plasma confinement go away when you're
             | just trying to squeeze as hard as you can and are willing
             | to use fission bombs to do it in an otherwise uncontrolled
             | manner.
             | 
             | Not if you want them to fit in a submarine warhead. This
             | sort of work is _not_ easy to do well.
        
               | ceejayoz wrote:
               | > And yet that's exactly why the NIF was actually built.
               | 
               | You're both half-right.
               | 
               | The NIF is the replacement for nuclear tests. It's
               | necessary to maintain the arsenal in a working fashion,
               | as the warheads degrade over time and have to be replaced
               | with new ones. https://www.npr.org/templates/story/story.
               | php?storyId=655921...
               | 
               | The NIF is not for _more powerful_ nuclear weapons, as
               | that 's entirely unnecessary. If anything, most interest
               | these days is in _less_ powerful weapons for potential
               | battlefield use.
        
               | cheriot wrote:
               | > And yet that's exactly why the NIF was actually built.
               | They do plenty of weapons research
               | 
               | It's not the _only_ thing they do.
        
           | Gatsky wrote:
           | Good things often have dubious or downright evil origins
           | (which would never be justifiable _a priori_ ).
           | 
           | A relatively recent example: development of cancer
           | chemotherapy began with the incidental finding that the
           | chemical warfare agent nitrogen mustard reduced the white
           | cell count of affected soldiers.
           | 
           | We make progress building on the shoulders of giants, but
           | those giants are often standing in dung.
        
           | Robotbeat wrote:
           | That isn't what this would be used for. In fact, yields for
           | the largest deployed H-bombs today I think are smaller than
           | they once were (due to better targeting capabilities).
        
             | tetha wrote:
             | This is true. The issue is that already a relatively small
             | nuclear weapon is perfectly sufficient to wipe out most to
             | all civilian structures. However, it does so in a roughly
             | circular area, and you need to increase the initial
             | explosion a royal lot to increase the devastated area by a
             | bit. And as you increase the overall spherical blast of the
             | weapon in order to increase the circle of doom on the
             | ground, more and more explosive power just vaporizes air.
             | 
             | That's why MIRV was introduced. One ICBM delivering 10 - 20
             | small warheads result in much greater devastation than an
             | equally heavy warhead in one package, because less power is
             | wasted on air and space.
             | 
             | It's morbid math, but it makes sense.
        
             | simiones wrote:
             | What do you think the US nuclear weapons research lab will
             | use their research for?
             | 
             | You're right that increasing the yield was a bad example
             | from my side, but the purpose is to improve the weapons,
             | nothing else.
        
               | hwillis wrote:
               | The B53 bomb was built in 1961 and it released 38 PJ or
               | 10 BILLION times more energy than this experiment. Data
               | gathered about plasma and fusion at NIF temperatures and
               | pressures is not helpful for the insanely different
               | environment of a nuclear bomb.
               | 
               | > What do you think the US nuclear weapons research lab
               | will use their research for?
               | 
               | Why do you think that _fusion_ is not enough? Complete
               | strategic energy independence for the US, and dominance
               | in the electricity sector? That 's so, SO much more
               | valuable than better nuclear weapons.
        
               | Robotbeat wrote:
               | The purpose of NIF, and it's not hidden, is to maintain
               | the existing US nuclear stockpile since we can no longer
               | rely on using underground nuclear weapon testing to
               | ensure they still work. There's a very big supercomputing
               | capability funded under the same effort. Instead of
               | testing the weapons by exploding them underground, we use
               | computer modeling with the modeling validated (ie backed
               | up) by experiment (at NIF) to make sure the stockpile
               | works and can maintain its strategic deterrent. The
               | euphemistic name for this is "stockpile stewardship."
        
           | badrabbit wrote:
           | You should be very excited because we live on a planet with
           | independent competing countries and well... you don't want to
           | live in the US or Europe with China or other not so friendly
           | countries building a bigger more powerful nuke. If a weapon
           | can be built, it will be built. How, when and if it can be
           | used are things you can control not whether someone somewhere
           | will develop it. Especially in war time, all bets are off.
           | 
           | Although, it would be interesting to see fusion reactors on
           | planes and ships powering other types of weapons like lasers
           | and more powerful railguns or faster icbms.
        
           | lizknope wrote:
           | Soviet Union built this and it wasn't really practical and
           | ended up leading to test ban treaties
           | 
           | https://en.wikipedia.org/wiki/Tsar_Bomba
        
         | rllearneratwork wrote:
         | I would love to see "fusion Manhattan project", this planet is
         | well overdue for new gigantic R&D projects such as Manhattan
         | and Apollo.
        
           | Victerius wrote:
           | Who are our modern J. Robert Oppenheimer, Enrico Fermi,
           | Richard Feynman, Edward Teller, John Von Neumann, and
           | Stanislaw Ulam?
        
             | rllearneratwork wrote:
             | off-topic, but related. Ulam's "Adventures of a
             | Mathematician" is an excellent and very inspiring book.
        
             | bioemerl wrote:
             | Hiding behind the names of institutions that got smart
             | enough to not give the peons fame or recognition.
        
             | StevenNunez wrote:
             | Elon Musk ::ducks::
        
               | vzcx wrote:
               | lmao, brilliant scientist Elon Musk is NOT. A closer
               | comparison would be general Groves, someone who can get
               | the team and resources in place so the work can get done.
        
               | Mistletoe wrote:
               | He's actually the complete opposite based on reports of
               | what it is like to work with him at SpaceX and Tesla in
               | recent years. Employees describe having to avoid him so
               | he doesn't meddle in the projects and screw them up.
               | 
               | Maybe he was like you describe long ago but
               | something...happened.
        
             | chasd00 wrote:
             | > Who are our modern J. Robert Oppenheimer, Enrico Fermi,
             | Richard Feynman, Edward Teller, John Von Neumann, and
             | Stanislaw Ulam?
             | 
             | they're working on getting you to click on an ad
        
               | [deleted]
        
               | rllearneratwork wrote:
               | yeah. But some are apparently working at Livermore Nat.
               | Lab still. Also, I feel like there is a bunch at SpaceX,
               | Tesla, NASA, DeepMind and OpenAI
        
               | Firmwarrior wrote:
               | Yeah, I think we have a lot of sleeper geniuses out there
               | 
               | I'm a pretty smart dude. I'm no big deal on HackerNews or
               | in Silicon Valley, but I look easily 10x as smart as most
               | of the normal people I come across in the real world. And
               | I regularly come across people so much smarter than me,
               | they have to explain things to me the same way I talk to
               | a toddler
               | 
               | I'll bet a lot of geniuses are congregating in cool orgs
               | like those where they can make a real difference in the
               | world.
        
               | euix wrote:
               | Hear hear!
        
               | phtrivier wrote:
               | They can't exist any more for structural reason.
               | 
               | This generation was classically educated, without TV or
               | social media in their childhood. They spent the time
               | we're wasting on HN reading _books_ and following the
               | discipline their elders learned in WWI. They had plenty
               | of occasions to tinker.
               | 
               | I claim the brains of those generation was structurally
               | different from ours, and we're talking about the best
               | minds of this generation.
               | 
               | It's a trope to say that our "best minds are working on
               | ads" - the reality is that, no, we webshits are not the
               | "best minds".
        
               | salmo wrote:
               | This general idea that a previous generation was better
               | because they lead a less pampered life goes back to some
               | of the earliest writing. Yet here we are.
               | 
               | World changing people seem to me to be very much the
               | right people in the right place at the right time. The
               | best way to find them is to try to create those places
               | now.
               | 
               | Opportunities for WWII and post-war era research don't
               | exist now. Everything with funding is very short term,
               | politicized, and narrowly focused within a micro
               | specialty.
               | 
               | Realistically, I don't think that will change until it
               | has to.
        
               | antonfire wrote:
               | > It's a trope to say that our "best minds are working on
               | ads".
               | 
               | "The last generation was better because they read _books_
               | and had _discipline_ and didn't waste their time on
               | frivolous garbage" is also a trope.
        
               | chrisbaker98 wrote:
               | Doesn't mean it's wrong.
        
               | fastball wrote:
               | It probably is though. Sure, they didn't have as much
               | distractions, but they also didn't have the sum total of
               | the world's knowledge at their fingertips in the same way
               | we do today.
               | 
               | People having been saying "this next generation is
               | inferior to the last one" since the ancient Greeks. If
               | that was consistently true we would already be in an
               | Idiocracy scenario.
        
               | phtrivier wrote:
               | > If that was consistently true we would already be in an
               | Idiocracy scenario.
               | 
               | Been on Twitter, Facebook, or Hacker News lately ?
               | 
               | More seriously, I really fear this kind of stuff is, to
               | some extend, new :
               | https://sitn.hms.harvard.edu/flash/2018/dopamine-
               | smartphones...
               | 
               | (Although, maybe it's comparable to the "opium epidemics"
               | of the 1800s ?)
               | 
               | Ironically, I should stop having this kind of
               | conversation... On social network.
        
               | govg wrote:
               | I mean, sure. But at the same time they were constrained
               | by the tools of their time, had no internet for instant
               | information access and spread, and scientific
               | collaboration has never been at a higher level than it is
               | now. There's no reason to believe that people who grow up
               | with instant lookup and massive computational power will
               | somehow be less capable than people whose only tools were
               | pen and pencil. What is possible now couldn't even be
               | dreamed of back then.
        
               | quickthrower2 wrote:
               | Webshits are not working on ads
        
               | adventured wrote:
               | > they're working on getting you to click on an ad
               | 
               | They're not, and there's zero evidence to back that
               | frequently floated premise up. That's a particularly
               | laughable myth created by those same industry people to
               | feel better about their terrible life choices. If you
               | can't do something meaningful, at least you can pretend
               | to be a genius doing nothing meaningful. It turns out
               | that both things are false, they're not brilliant and
               | they're wasting their lives.
               | 
               | No, the brilliant people are working at TSMC, Intel, AMD,
               | nVidia, Applied Materials, ASML, Illumina, ARM, TI, et
               | al.
               | 
               | They're working on CRISPR. They're working on mRNA
               | vaccines. They're working on stem cells. They're trying
               | to cure HIV just as the same type of people cured
               | hepatitis C. They're working for Moderna, Pfizer,
               | BioNTech, Roche, Novartis, Amgen, Regeneron, Sanofi,
               | Gilead, Merck, Glaxo, et al. They're trying to figure out
               | how to roll back or cure Alzheimer's. They're dedicating
               | a lifetime of work into exploring the human genome, so
               | that future generations have a much better, much more
               | useful map.
               | 
               | They're working on robotics at Intuitive Surgical or
               | Boston Dynamics. They're working on self-driving tech.
               | They've been building out the massive, global cloud
               | infrastructure. They're at NASA, or SpaceX, or ESA and
               | they're doing the work to get us a base on the moon or to
               | Mars. They just got done building rockets that can land
               | upright. They're building a massive, extraordinary,
               | global satellite system in Starlink.
               | 
               | They're working on fusion.
               | 
               | And so on and so forth.
               | 
               | Ad clicks? Yeah right. They're not even in the room.
        
               | whiplash451 wrote:
               | Wow. That was long overdue. Thank you!
        
               | lifeformed wrote:
               | A lot of wonderful people are doing that, but do those
               | jobs pay anywhere close to the ad companies? Surely
               | there's a lot of bright minds lost to the allure of
               | money.
        
               | illirik wrote:
               | At this point, it's not even about "money" in the
               | traditional sense (wealth, prestige, etc.); rather, it's
               | about stability, the alleged "American dream". I live in
               | Chicago, so I'll consider the local national laboratory,
               | Argonne. They pay their software engineers $101,888 per
               | year, according to Glassdoor ($71,640 after state and
               | federal tax). Using the 28% rule most lenders use
               | nowadays, with today's rates, that's a maximum mortgage
               | payment of $1,671 at 7%. However, the median house price
               | in DuPage County is $335,000 [1], and a 30-year mortgage
               | (with 10% down) has a monthly payment of just over
               | $2,000. No dice - even for a highly skilled professional
               | living in one of the most affordable parts of the
               | country. Keep in mind that you still need to pay 2.3% per
               | annum property tax, besides owning a car and saving for
               | retirement. It's just not nearly as feasible a path
               | towards financial stability as taking a $"TECH" job with
               | west coast pay.
               | 
               | [1] This is up 1.1% year-over-year, and only up 6.5% p.a.
               | over the last three years - not a pandemic-driven bubble.
               | Source is https://www.redfin.com/county/733/IL/DuPage-
               | County/housing-m...
        
               | antipotoad wrote:
               | Thank you for this, sincerely.
        
         | tootie wrote:
         | There are already funded commercial fusion projects underway.
         | No idea which will bring a product to market first or at all,
         | but they suddenly seem a lot more plausible.
         | 
         | https://www.nytimes.com/2021/08/10/technology/commonwealth-f...
        
         | dleslie wrote:
         | The question on my mind is: where do I sign up to join this
         | effort?!
         | 
         | Edit: I'm Canadian, the question is rhetorical.
        
           | brianyu8 wrote:
           | Assuming you have experience in software, then
           | https://www.llnl.gov/join-our-team/careers/find-your-
           | job/0d6...
        
             | [deleted]
        
             | lostmsu wrote:
             | Aren't they required to post salary ranges by some
             | Californian law?
        
               | donquixote25 wrote:
               | Law goes into effect next year.
        
               | emmp wrote:
               | These are federal jobs so all of the pay bands are public
               | knowledge.
        
               | dplavery92 wrote:
               | This is not quite correct. LLNL is a Federally Funded
               | Research & Development Center (FFRDC) which is owned, as
               | a facility, by the government, but managed and staffed by
               | a non-profit contracting organization called Lawrence
               | Livermore National Security, LLC (LLNS) under a contract
               | funded by DOE/NNSA. The board of LLNS is made up of
               | representatives from universities (California + TAMU),
               | other scientific non-profits (Battelle Memorial
               | Institute), and private nuclear ventures (e.g. Bechtel.)
               | LLNS pays, with very few exceptions, staff salaries at
               | LLNL, and they are not beholden to the government
               | civilian pay schedule.
               | 
               | https://www.llnl.gov/about/management-sponsors
        
               | cheriot wrote:
               | Is it enforceable on the Feds?
        
             | lostmsu wrote:
             | BTW, they don't seem to have software roles at NIF:
             | https://www.llnl.gov/join-our-team/careers/find-your-
             | job/liv...
        
           | arbuge wrote:
           | https://www.llnl.gov/join-our-team/careers
        
           | wedn3sday wrote:
           | Former LLNL employee here, they hire a LOT of foreign
           | nationals. Several people that I worked with there were
           | Canadian.
        
             | dplavery92 wrote:
             | Be that as it may, a number of positions at LLNL, including
             | many of those affiliated with NIF, require that candidate
             | is a US person and is eligible for a DOE security
             | clearance. A security clearance is not necessarily binary
             | on being a US person, but a number of national-security
             | related positions may require not only the clearance, but
             | also that the candidate is a US person (or outright forbid
             | foreign nationals.)
        
           | lambdatronics wrote:
           | There's always General Fusion.
        
           | [deleted]
        
           | lizknope wrote:
           | Google "national ignition facility careers" and this is the
           | first link
           | 
           | https://lasers.llnl.gov/about/careers
        
         | opportune wrote:
         | 100% agree. We should be dumping as much as we can in getting
         | fusion up and running ASAP. It could be a silver bullet to stop
         | climate change alone, and by driving energy costs lower, enable
         | huge innovations in AI/automation and increasing material
         | wealth.
         | 
         | $1T to move fusion forward just 5 years from eg 2040 to 2035
         | could alone have a huge ROI in terms of climate mitigation and
         | decarbonization
        
           | stonepresto wrote:
           | Way more than that. This would shift the entire geopolitical
           | structure of the world. Humanity would never be the same.
        
             | fosk wrote:
             | Good riddance.
        
           | propogandist wrote:
           | > silver bullet to stop climate change alone
           | 
           | nothing will stop climate change. The earth's climate will
           | continue to change regardless of any human interventions
        
           | vincnetas wrote:
           | With abundant electricity wouldn't we face another type of
           | global warming? We will would start to consume so much
           | electricity that this will heat up the planet?
        
             | defrost wrote:
             | Relative scales of various factors matter here:
             | 
             | We _aren 't_ "heating up the planet" .. we're "insulating
             | the atmosphere".
             | 
             | Increased C02 (and the close following methane and water
             | vapor increases) serve to trap _more_ of the heat radiated
             | outwards that would otherwise escape.
             | 
             | The vast _bulk_ of that heat comes from the visible light
             | of the sun which passes easily through the atmosphere
             | coming in, gets converted to IR energy as it warms the
             | earth and oceans, and then escapes outwards.
             | 
             | Our changes to the atmosphere have disturbed that balance.
             | 
             | Your comment has _some_ small merit, but you would need to
             | work through the heat output of human generated power and
             | then compare that to the daily heat energy originally from
             | the sun that radiates outward.
        
               | mcculley wrote:
               | > We aren't "heating up the planet" .. we're "insulating
               | the atmosphere".
               | 
               | We are doing both. We are doing more insulating than
               | heating, but we obviously generate more heat.
        
               | defrost wrote:
               | Did you _actually read_ my comment to the end?
               | 
               | If so, how'd you do on the numbers?
        
               | mcculley wrote:
               | Of course I did. It is rude to suggest otherwise. Your
               | blanket assertion followed by your long explanation is
               | confusing and less helpful to anyone asking the original
               | question than it would be without it.
        
               | defrost wrote:
               | Good, so by what rough order of magnitude does the sun
               | heat us up more than human power generation then?
               | 
               | Is it x10, x100, x1000, .. more?
               | 
               | This is after all the part that matters.
        
               | mcculley wrote:
               | I have no idea. Obviously we get more heat from the sun
               | than we generate on our own. That does not make your
               | blanket assertion true.
               | 
               | The original question is a good one. We will use more
               | energy as it gets cheaper (see monster trucks, Las Vegas,
               | Dubai). We should be thinking of what we will do with the
               | waste heat when everyone has a fusion reactor.
        
             | nova22033 wrote:
             | I'm not going to set my thermostat to 78 degrees because
             | electricity is practically free.
        
               | vincnetas wrote:
               | But some people would start driving 6 ton vehicles
               | because fuel is free. Limiting factor for crytpo mining
               | would be only number of hardware you can get (provided
               | crypto survives for so long). Some people would probably
               | do the math and decide that thermal insulation is too
               | expensive, and run heating/cooling on max. I could
               | probably come up with more examples.
               | 
               | EDIT: from quick google query it looks like per day earth
               | receives equivalent of yearly power consumption (not only
               | electricity but also fuel). So we would need to x356 our
               | energy consumption which is not that much unreasonable if
               | you could have for example heated outdoor pool for free
               | anywhere in the world.
        
           | oreilles wrote:
           | Cheaper and cleaner energy has never in the history of enery
           | lead to global reduction of pollution, actually pretty much
           | the opposite. Plus, nuclear power is already virtually free
           | and has been available since the 1970s. If stopping climate
           | change was an energy source problem, it would have already
           | been solved then.
        
             | tomComb wrote:
             | "nuclear power is already virtually free"
             | 
             | What? Cost is THE problem with nuclear energy.
             | 
             | You must have some bizarre way of framing things to make
             | today statement - you should at least tell us what that is
             | since you must know that you are making a controversial
             | claim.
        
             | fastball wrote:
             | Basically the only energy that is cheaper and cleaner than
             | fossil fuels is wind and solar, which have only gotten to
             | that point in the last 1-2 decades, so it seems difficult
             | to make claims about what has happened in "history".
        
             | opportune wrote:
             | I'm not anti fission. But the reality is that many are and
             | the NIMBY effect is strong. You don't necessarily have that
             | with fusion.
             | 
             | Also, there should hopefully be much less pomp and process
             | around fusion compared to fission due to the
             | safety/radiation profile being much safer.
        
           | sAbakumoff wrote:
           | LMAO. Good luck to get funding passed through GOP-controlled
           | congress with all these oil and gas companies rallied behind.
           | There is zero chance that the USA will ever do that.
        
           | iamgopal wrote:
           | How easy is to write $1T, but with that you can basically
           | install enough solar cell to power all of USA energy need.
        
             | thehappypm wrote:
             | Fusion can give us 10x our energy need. Imagine a world
             | where energy is simply not a blocker for anything.
        
             | willmadden wrote:
             | Solar can't do that without massive batteries that don't
             | exist. Even then it's not viable in areas where there isn't
             | sufficient sunlight.
        
               | valine wrote:
               | The batteries do exist, but it's better to use them in
               | cars. If we start diverting our battery supply for grid
               | storage it will drive up the price of EVs.
        
             | RobinL wrote:
             | Here's some rough numbers, hopefully i haven't made any
             | mistakes:
             | 
             | Total US energy generation 2021: 4 trillion kwh
             | 
             | Average power generation: 457Gw
             | 
             | Cost of Topaz solar farm: $2.5bn Potential output: 550 Mw
             | Cost per Mw $4.5m
             | 
             | Spend a trillion on similar capacity, you get 220Gw
             | potential output.
             | 
             | But that's assuming you get 550Mw average. In fact, it
             | produces about 1282Gwh output a year, so average is more
             | like 145Mw.
             | 
             | So at a rough estimate, you need more like 10 trillion to
             | meet US electricity demand. And that assumes you have
             | unlimited battery storage for free.
             | 
             | And of course electricity is a small minority of total
             | energy use.
             | 
             | Incidentally, I think it's amazing you get to about 10% of
             | total electricity needs with only $1tr, i.e. around 4% of
             | US national output.
             | 
             | https://en.wikipedia.org/wiki/Topaz_Solar_Farm https://www.
             | eia.gov/energyexplained/electricity/electricity-...
             | 
             | ```python trillion_dollars = 1e12
             | 
             | mw = 550
             | 
             | cost_farm = 2.5e9
             | 
             | cost_dollar_per_mw = cost_farm/mw
             | 
             | num_mw = trillion_dollars/cost_dollar_per_mw
             | 
             | num_gw = num_mw/1000
             | 
             | num_gw
             | 
             | kwh = 4e12
             | 
             | mw = kw/1000
             | 
             | gw = mw/1000
             | 
             | gw ```
        
             | dahfizz wrote:
             | <during the day>. $1T doesn't buy nearly enough batteries
             | for the storage we would need.
             | 
             | We should be installing more solar & wind, but that alone
             | is not a solution to our problems.
        
             | bboygravity wrote:
             | No you can't because solar isn't a continious source and
             | fusion is.
             | 
             | No amount of investment into solar power can make the sun
             | magically shine 24 hours a day.
        
               | atoav wrote:
               | Energy storage is not an unsolved issue.
        
               | Cort3z wrote:
               | Batteries
        
               | joe_the_user wrote:
               | Of course you can invest enough and make solar equivalent
               | to continuous power.
               | 
               | Solar + reverse hydropower, solar + synthetic fuel
               | manufacture, solar + appropriate sized batteries, solar
               | cranes-with-weights, etc.
               | 
               | Solar is so cheap that all those are plausible. Fusion is
               | still far from ready.
        
               | Helmut10001 wrote:
               | I suggest we do not lay all of our eggs in one basket.
               | Climate change can be best countered if we use the sweet
               | spot of all current available and anticipated
               | technologies, including photovoltaic, long & short term
               | storage solutions, and fusion. There is no need to bet on
               | one technology at this stage.
        
               | Tade0 wrote:
               | There is a market need.
               | 
               | Solar panels are cheap and the market appears to be fine
               | with unreliable power[0] if it's cheap enough.
               | 
               | [0] Unreliable, but predictable that is. You can estimate
               | with decent confidence what the weather will be like
               | tomorrow and you can definitely tell what it's going to
               | be a few hours from now, so energy auctions a day ahead
               | are feasible.
        
               | liketochill wrote:
               | Do you have week long blackouts currently? In any given
               | year you can count on a week where a panel only produces
               | 10%. It just has to be cloudy or rainy. However much
               | solar we add, even with storage to get through a night,
               | needs some other source to get through the cloudy week,
               | unless we are ok with blackouts.
        
               | Tade0 wrote:
               | _A_ panel. Panels spread over hundreds of thousands of
               | square kilometres produce power averaged over that area,
               | so they 're much more consistent and predictable.
               | 
               | HVDC lines help with this a lot. It has gotten to a point
               | where there are serious plans to build a long, undersea
               | HVDC line from the UK to Morocco which, get this, is
               | poised to cost less than the equivalent(GWh delivered
               | annually) Hinkley Point C nuclear power plant:
               | 
               | https://xlinks.co/morocco-uk-power-project/
               | 
               | That's how cheap the combination of solar and HVDC is.
        
               | liketochill wrote:
               | Glad it will work there. There has been local opposition
               | to new transmission lines in the USA (see Maine recently)
               | so when folks say "just build powerlines" all I can think
               | of is the difficulty of the land assembly and permitting.
               | Technically it is easy, it is all the humans in the way
               | that make it hard.
        
               | ramijames wrote:
               | I mean, you could literally build a ring of solar power
               | collectors and microwave transmitters in orbit. It would
               | always have 50% coverage.
        
               | HPsquared wrote:
               | Or just have a bunch of power lines running east-west.
        
           | markasoftware wrote:
           | Will not be a silver bullet, electricity production
           | contributes less than half of global CO2 emissions. Still
           | need other solutions for transport, industrial processes,
           | agriculture, etc.
           | 
           | Further, it's possible that fusion plants might be
           | prohibitively expensive to build and maintain, even if their
           | fuel is cheap.
        
             | discordance wrote:
             | If there's a glut of cheap electrical energy, there would
             | be a rapid push to electrify things like iron and steel
             | production (8% of emissions), heating (10% of emissions)
             | and transportation (10%)... and so on.
        
             | opportune wrote:
             | I'm not thinking about just replacing grid energy, but
             | carbon removal. If we can get fusion scaled up and
             | efficient it should be no sweat to use it to just remove
             | carbon from the air
             | 
             | In fact carbon removal might be a great way to subsidize
             | fusion at the outset so that it can be overprovisioned/have
             | a guaranteed minimum price
        
               | vlovich123 wrote:
               | $600 per ton of CO2. The industry is trying to get to
               | $100 per ton of CO2.
               | 
               | Energy estimated is 1,200 kilowatt-hours per ton of CO2
               | removed.
               | 
               | Nuclear fission energy averages 0.4 cents/kWh. That's
               | $480 in energy costs alone (ignoring profit margins for
               | removal, etc).
               | 
               | Why would bleeding edge fusion that requires cutting edge
               | lasers, magnets, and various other containment stuff have
               | a cheaper energy generation cost? I could be wrong, but I
               | don't think nuclear waste (which is the primary
               | difference with fusion) is the primary cost contributor.
               | So why would you want to invest in more expensive fusion
               | to remove all this carbon instead of cheaper fission?
               | Nuclear waste by the way isn't waste. It can be reused in
               | breeder reactors and it's used a lot in medicine (I could
               | be wrong but one of the reasons nuclear imaging has
               | gotten more expensive is because radioactive materials
               | are more difficult to obtain due to reduction in global
               | fission energy).
        
               | postingawayonhn wrote:
               | Fusion plants should be able to save a lot of money
               | though simpler permitting processes, not needing the same
               | level of containment structures, needing less security,
               | and less regulator scrutiny. The equipment itself might
               | be more expensive at the start but if we build these
               | plants at scale those costs should reduce over time.
        
               | vlovich123 wrote:
               | The first commercial reactor designs are probably 50
               | years away and another 50 years before costs come down to
               | be reasonable / we can build enough to start replacing
               | existing fission and coal. This is from the CEO of
               | General Fusion a leader in the space. I think if even the
               | fusion people are saying "build fission today to solve
               | global warming" then that tells you something about the
               | time scale this is happening on.
               | 
               | I suspect the regulatory environment is from regulatory
               | capture by the fossil fuel industry. Otherwise why would
               | Gen IV reactors, which can't meltdown, be suffering many
               | regulatory delays? What kind of nuclear proliferation
               | concerns exist for reactors built and deployed within the
               | US?
        
               | opportune wrote:
               | Those are figures for current electrical production
               | schemes.
               | 
               | After decades of R&D fusion should become significantly
               | cheaper than fission per kWh if only due to having less
               | of a regulatory burden and smoother permitting process.
               | 
               | It's more expensive now, but in the long run it will be
               | cheaper.
        
               | vlovich123 wrote:
               | You hope. It's not "more expensive now". It's infinitely
               | more expensive because we can't even build one. It's
               | unclear how much a fusion reactor will end up costing but
               | I wouldn't use hope to blind myself into thinking it'll
               | be 10x cheaper than fission. There's certainly reason to
               | be hopeful because solar and wind are cheaper, but
               | construction for those is also relatively simple and easy
               | to mass manufacture most of it. Fusion reactors will
               | probably look more like fission than not (ie complex to
               | mass manufacture, still require complex structures, need
               | regular complicated maintenance due to radioactive decay
               | in the containment materials etc). Additionally, solar
               | and wind don't pose real threats to established fossil
               | fuel interests. Fusion would and it's unclear how they
               | might respond from a regulatory hurdle perspective.
        
             | ShakataGaNai wrote:
             | There are a lot of bigger picture items around energy. Part
             | of Europe's challenge with the war in Ukraine is that a lot
             | of countries buy Russian gas & oil.
             | 
             | >Russia accounted for about 55% of Germany's natural gas
             | imports and 35% of Germany's oil imports last year, causing
             | Germany to resist a blanket European Union ban on Russian
             | energy.
             | 
             | If every country could assure their energy independence,
             | geopolitics would look very different. Yes, there are still
             | many problems, like natural resources. But if you can
             | assure all your residents can keep the lights on, their
             | houses warm and the economy moving (EV's for transit,
             | technology)... its very reassuring.
        
             | hn_throwaway_99 wrote:
             | People should understand that it is _all_ an energy
             | problem, regardless of how that energy is currently
             | delivered. Transportation can be (and, of course, is being
             | electrified), most industrial processes and agriculture
             | currently use fossil fuels as inputs because its the
             | cheapest source of input.
             | 
             | For example, nitrogen fixation for fertilizer currently
             | uses natural gas almost entirely for the source of
             | hydrogen. Vastly cheaper energy means it would make much
             | more sense to switch this to electricity, https://www.front
             | iersin.org/articles/10.3389/fenrg.2021.5808....
             | 
             | But I agree with your sentiment, there are a _lot_ of
             | engineering details to consider before one can shout  "free
             | energy".
        
             | postingawayonhn wrote:
             | Most of those other things you mention can be electrified
             | with current technology. Once that happens we'll need the
             | electricity to power them.
        
         | sbaiddn wrote:
         | TL/DR
         | 
         | Lasers are pretty inefficient. How much energy did it take to
         | make 2.05 MJ of lased light?
         | 
         | Does this breakthrough have a reasonable path to to make more
         | electrical energy than it puts in?
        
         | mytailorisrich wrote:
         | Most of the funding for the Manhattan project went into the
         | industrial infrastructure required to produce plutonium and
         | enriched uranium.
         | 
         | It will be time to unleash resources once they have a working
         | fusion reactor design in order to build fusion power plants and
         | the industrial infrastructure required to supply them.
         | 
         | Until then they should of course get the resources they need
         | but I don't think throwing money at them will necessarily speed
         | things up.
        
           | aidenn0 wrote:
           | A uranium-gun bomb has a very simple theoretical basis, but
           | enriching uranium is very expensive (and was even more
           | expensive in the 1940s. Producing enough enriched uranium was
           | the only hard problem in making that bomb; in fact they did
           | not even test the bomb before dropping it on Hiroshima
           | because they were fairly sure it was going to work and
           | wouldn't have enough enriched uranium for a second bomb on
           | the timelines involved.
           | 
           | Plutonium was significantly more easy to produce, but it did
           | require some novel engineering for the implosion lens. They
           | weren't sure it was going to work and did, in fact, test the
           | bomb before dropping it on Nagasaki.
           | 
           | I think the Manhattan project is a great example of where
           | more funds can help; if the funds were more restricted, it's
           | entirely possible they would have gone with the "sure thing"
           | of the uranium bomb instead of spending resources on the less
           | sure plutonium bomb. Trying out multiple ideas in parallel
           | often "wastes" money since if you try ideas in tandem, you
           | will always try the high-percentage ideas first.
        
       | mlindner wrote:
       | The design of the National Ignition Facility was never intended
       | to study commercially viable fusion power. It's exclusively a
       | physics testing facility with origins for testing the physics of
       | thermonuclear fusion weapons for better bomb design.
       | 
       | Nothing that happens at the NIF is very useful in heading towards
       | commercially viable fusion. The design of the testing apparatus
       | is also similarly incompatible with making a sustained fusion
       | device as there is no way to continuously feed in fuel into the
       | device, nor methods of extracting the energy.
        
         | seandoe wrote:
         | Swaying public perception in an optimistic direction is enough
         | of an effect to justify the cost and effort of this
         | achievement.
        
         | EamonnMR wrote:
         | Those sound like problems less complicated than a huge array of
         | laser beams, but the devil's in ths details I suppose.
        
       | brianyu8 wrote:
       | What an amazing achievement. I was curious, so I looked up the
       | open software roles at LLNL[0]. I'm very curious how the salary
       | compares to your average bay area tech salary.
       | 
       | [0]: https://www.llnl.gov/join-our-team/careers/find-your-
       | job/0d6...
        
         | nonethewiser wrote:
         | See for yourself https://www.glassdoor.com/Salary/Lawrence-
         | Livermore-National...
         | 
         | 145k TC for Software Engineer. Better than I'd expect from a
         | government job, although a qualified applicant could obviously
         | make so much more elsewhere. And supporting the needs of a
         | bunch of PhD's doesn't really sound fun.
        
       | pdonis wrote:
       | Calling this "ignition" is a misnomer. The correct term, as given
       | in the article (as opposed to the headline) is exceeding
       | breakeven: more fusion energy output than energy input to the
       | target.
       | 
       | "Ignition" means the reaction becomes self-sustaining and does
       | not require any further input of energy to continue.
        
         | donquixote25 wrote:
         | No, this is ignition. However, the reason why this is a big
         | deal is because it is scientific break-even.
         | 
         | The first time they achieved ignition was in August of 2021.
         | See paper below:
         | 
         | https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.12...
        
         | Robotbeat wrote:
         | They actually achieved both ignition and scientific breakeven.
         | The resultant fusion heat helped produced significantly more
         | fusion, not just relying on external energy (ie from the laser
         | implosion).
        
         | dogma1138 wrote:
         | And it was just that the after the initial laser pulse that
         | triggered ignition there was no need to sustain it to continue
         | to heat up the fuel to induce fusion.
         | 
         | The fact that this indeed was ignition was one of the main
         | reasons why the fusion reaction itself was net positive.
        
           | pdonis wrote:
           | _> it was just that the after the initial laser pulse that
           | triggered ignition there was no need to sustain it to
           | continue to heat up the fuel to induce fusion_
           | 
           | I don't see this anywhere in the article. Is there a better
           | reference for what actually happened during the experiment?
        
         | lostmsu wrote:
         | > the reaction becomes self-sustaining
         | 
         | This is applicable only to continuously running reactions like
         | in jet engines.
        
           | pdonis wrote:
           | Which would also include any other method currently being
           | pursued to achieve fusion, besides laser confinement. I'm
           | guessing that the laser confinement community had to invent
           | another meaning for "ignition" since the usual one would not
           | be applicable to them.
        
       | apienx wrote:
       | Exciting! Is this work published somewhere? I'm curious to hear
       | more about the setup and other experimental conditions.
        
       | afiori wrote:
       | I recommend reading [0] for (only slightly outdated) context on
       | the field and its progresses.
       | 
       | [0] https://astralcodexten.substack.com/p/your-book-review-
       | the-f...
        
       | TEP_Kim_Il_Sung wrote:
       | Thank you, Biden!
        
       | dqpb wrote:
       | > maintaining a nuclear deterrent without nuclear testing
       | 
       | What is meant by this?
        
         | julienreszka wrote:
         | Since the Treaty Banning Nuclear Weapons Tests in the
         | Atmosphere, in Outer Space, and Under Water was signed in 1963,
         | all nuclear weapons tests must be performed underground. This
         | is typically done by digging a deep shaft or tunnel in the
         | earth and detonating the weapon at the bottom of the shaft or
         | tunnel. The explosion is monitored by a variety of equipment,
         | such as seismographs, radiation detectors, and air samplers.
         | The data gathered from these tests helps to understand the
         | weapon's performance and its potential impact.
         | 
         | In addition, computer simulations are often used to test the
         | effects of a nuclear weapon, such as the predicted fallout and
         | atmospheric effects. These simulations are based on data
         | collected from previous nuclear tests as well as theoretical
         | models.
        
           | dqpb wrote:
           | Is this ChatGPT? It doesn't answer the question.
           | 
           | When I ask ChatGPT it says:
           | 
           | "fusion is not directly related to nuclear weapons or the
           | maintenance of a nuclear deterrent"
        
             | julienreszka wrote:
             | In other words research in fusion helps make more accurate
             | simulations of how nuclear weapons would behave.
             | 
             | >fusion is not directly related to nuclear weapons or the
             | maintenance of a nuclear deterrent
             | 
             | ChatGPT is wrong in this case. Fusion occurs in hydrogen
             | bombs i.e. nuclear weapons
        
       | s_dev wrote:
       | Christopher Nolan couldn't have timed the release of Oppenheimer
       | better.
        
         | falcor84 wrote:
         | Well, it would have been better if the release date was this
         | week, no? (I see it's currently scheduled for 2023-07-21)
        
       | ck2 wrote:
       | This was for a few seconds using radioactive "fuel" correct?
       | 
       | So perpetually 10-25 years away at all times?
       | 
       | https://m.xkcd.com/678/
       | 
       | Beware science packaged as press-releases.
        
       | JaggerFoo wrote:
       | Ok, so how long do I have to wait to get a coffee-can sized
       | device to power my house?
        
       | JohnBerea wrote:
       | Let's say this all works out and over the next few decades fusion
       | replaces all other electricity generation, and we're past the
       | point where all the initial infrastructure costs have been paid
       | for.
       | 
       | How much will my electric bill be reduced?
        
         | Ancalagon wrote:
         | Initial investment cost to build reactors would in all
         | likelihood be very high just by the nature of these being some
         | of the most complex machines on the planet. It seems unlikely
         | any sort of fast manufacturing line could be created to build
         | these, and they'd all likely be built one at a time like
         | fission reactors.
         | 
         | Running costs and maintenance would also be high, the fuel
         | alone is expensive (right now), and I've heard that wear and
         | tear on parts of the reactors can be high so much of the
         | housing for the reactor would need to be replaced with time.
         | 
         | You've probably also got a small army of engineers running each
         | one of these reactors you've got to pay.
         | 
         | All that said, the energy produced via fusion is EXTREMELY
         | abundant. I imagine with later reactor iterations (after supply
         | chains have been setup and electrical transportation routes
         | upgrades) electricity could become very cheap even relative to
         | renewables.
        
         | drusenko wrote:
         | If you live in California, even if electricity generation cost
         | nothing at all it would still only lower your bill by ~15%.
         | Transmission & distribution of electricity is the expensive
         | part not generating it. It doesn't _need_ to be expensive, yet
         | here we are.
        
         | happyopossum wrote:
         | This is kind of a silly question given the time horizons and
         | other potential factors that can crop up in 30 years, but my
         | electric bill has separate charges for generation and delivery.
         | Even if generation drops by 90%, it'd still only cut my bill in
         | half.
        
         | chasd00 wrote:
         | i doubt your electric bill would be reduced at all. It would
         | probably increase at a more constant rate instead of dramatic
         | ups and downs though. So there's that..
        
         | dotancohen wrote:
         | > How much will my electric bill be reduced?
         | 
         | Your bill will be the same, or higher. But you'll be doing so
         | much more with electricity. Push a button, and your clothes are
         | clean in seconds. Push a button, and your beard is shaved in
         | seconds. Push a button, and four of your five senses are
         | entertained for hours.
        
           | nonethewiser wrote:
           | Why cant you currently do those things then?
        
             | dotancohen wrote:
             | I'm unaware of a clothes washing machine currently on the
             | market that finishes the job in seconds. I believe that the
             | technology has yet to be introduced.
        
               | mbg721 wrote:
               | When it is, how many seconds-long washings will my
               | cheaply-made shirts survive? My guess is nearly one.
        
               | dotancohen wrote:
               | I suppose that you don't remember when the microwave oven
               | was introduced. Food warm in 60 seconds? Nuking it? It
               | will destroy all the nutritional value, it was said. I
               | remember people, including my family, excusing the fact
               | that we owned a microwave oven with the phrase "hospitals
               | use it".
        
       | nsxwolf wrote:
       | What's the difference between "ignition" and every other "fusion
       | achieved" news story I've seen in the last 40 years?
       | 
       | This has the feel of those "water discovered on Mars for the
       | first time ever" headlines.
        
         | 93po wrote:
         | My laymen understanding is that this is showing the first net-
         | positive energy fusion, which has always been the biggest
         | roadblock.
        
         | omnicognate wrote:
         | Well, for one thing achieving it is the purpose for which the
         | "National Ignition Facility" was created. It's right there in
         | the name. They're justified in having a bit of a party about
         | it.
        
       | raydiatian wrote:
       | > achieve President Biden's goal
       | 
       | This seems unnecessarily partisan to mention
        
         | alexose wrote:
         | The full quote is
         | 
         | > This historic, first-of-its kind achievement will provide
         | unprecedented capability to support NNSA's Stockpile
         | Stewardship Program and will provide invaluable insights into
         | the prospects of clean fusion energy, which would be a game-
         | changer for efforts to achieve President Biden's goal of a net-
         | zero carbon economy.
         | 
         | That is his administration's goal, and it's the directive that
         | DoE is working under during his presidency.
         | 
         | Unless you have another party in mind that's been vocally
         | championing a net-zero carbon economy?
        
           | raydiatian wrote:
           | Thank you for educating me. I was unaware Joe Biden invented
           | the concept of bringing down CO2 emissions. It's important
           | that we're calling him out by name so that we can illustrate
           | the sixty years of effort put forth by the hard working men
           | and women in nuclear physics. It is, after all, his money
           | that is funding this research effort.
           | 
           | Sincerely, a Biden voter
        
           | anon291 wrote:
           | The GOP has been pro-nuclear for a long time.
        
           | SoftTalker wrote:
           | This work is the result of decades of effort under many
           | administrations. This PR piece makes it sound like it all
           | happened in the last two years under Biden-Harris and a set
           | of Senators and Representatives who all happen to be from one
           | party. I had to stop reading to get the vomit taste out of my
           | mouth.
        
           | johnp271 wrote:
           | Wow so all this was accomplished starting from scratch in
           | January 2021. Given another year or two and a second Biden
           | term we should be finished.
        
         | desertlounger wrote:
        
           | raydiatian wrote:
           | If they could, literal reptiles would absolutely be in
           | support of this.
           | 
           | Because Godzilla.
        
         | valine wrote:
         | I am okay with any amount of partisanship if it means more
         | funding for fusion research.
        
       | mFixman wrote:
       | Widespread energy generation nuclear fission is politically
       | impossible in most Western countries.
       | 
       | Why are people optimistic that fusion won't have the same kind of
       | problems, such as new plants being too expensive to build and old
       | obsolete plants being too useful to decommission?
        
         | fullstackchris wrote:
         | I'm sure they said the same thing about coal plants before any
         | of them ever existed
        
         | dontwearitout wrote:
         | Fission's amazing potentially is nerfed by three main things:
         | proliferation risk, meltdown risk, and waste handling. These
         | are all solved problems but dramatically raise the cost (you
         | need armed guards, and the reactor has to be built to withstand
         | a 747 strike, etc etc). The fuel cost is a very small fraction
         | of the price of nuclear.
         | 
         | If you can eliminate or reduce the need for armed guards and
         | mountains of red tape, this has the potential to solve many of
         | fission's problems while providing the same benefits (unlimited
         | zero carbon power with dirt cheap fuel).
        
         | risyachka wrote:
         | The main backlash for fission is not cost but danger.
         | 
         | Fusion removes it.
        
         | BudaDude wrote:
         | I'm a bit more optimistic about this. This technology will be
         | more important for space exploration than it will be
         | (currently) on the ground.
        
         | DoughnutHole wrote:
         | > such as new plants being too expensive to build and old
         | obsolete plants being too useful to decommission?
         | 
         | There's no guarantee that these issues will be surmountable.
         | 
         |  _But_ fusion largely avoids the fear association with past
         | fission disasters and fears about nuclear waste. This is a non-
         | trivial political problem in many parts of the world,
         | especially much of Europe. If fusion becomes economical (big
         | if) and the differences between it and fission are well
         | communicated it might be easier for the world to swallow.
         | 
         | I think visions of a 100% fusion world are fairly pie in the
         | sky. Most of our energy most of the time will probably come
         | from already viable renewables. But renewables cannot offer
         | consistent baseline power all day, year-round, in every part of
         | the world. We need either huge breakthroughs in storage, or
         | carbon-free baseline generation. Economical fusion if it were
         | achieved _could_ offer that without some of the most
         | politically difficult drawbacks of fission.
         | 
         | I'd probably still bet the farm on renewables + storage though,
         | at least for my lifetime.
        
         | BeetleB wrote:
         | IIUC, there is no concern about radioactivity with fusion.
        
         | kzrdude wrote:
         | It is already widespread, being used for 10-20% of US energy,
         | isn't it? And 30-40% in several European countries. I think
         | it's definitely possible since it's already in place, we just
         | need to talk about it more.
        
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