[HN Gopher] Iron fuel shows its mettle
___________________________________________________________________
Iron fuel shows its mettle
Author : mfiguiere
Score : 183 points
Date : 2023-06-23 14:48 UTC (1 days ago)
(HTM) web link (spectrum.ieee.org)
(TXT) w3m dump (spectrum.ieee.org)
| j-a-a-p wrote:
| Looks like the same thing as Form Energy provides. They are
| selling plants at MW level (article is about a small brewery at
| kW level)
|
| https://formenergy.com/
| olau wrote:
| Form Energy is a bit light on details, but it looks like they
| are using a water based electrolyte, add oxygen, get electric
| power and rust when discharging, then add electric power and
| get iron and oxygen when charging.
|
| The project mentioned here is setting the iron powder on fire
| and need to use a steam turbine to get electric power out of
| it. So different tech.
| j-a-a-p wrote:
| > _Our first commercial product is an iron-air battery
| capable of storing electricity for 100 hours at system costs
| competitive with legacy power plants._
|
| https://formenergy.com/technology/battery-technology/
|
| But yes, I was triggered with iron alone, but they both seem
| to burn iron. There is a whole industry of flow batteries
| emerging also.
| howlin wrote:
| I don't really understand why iron is being considered over
| aluminum. Is aluminum production from ore too complex compared to
| iron? I would have to imagine burning metallic aluminum produces
| much more energy per gram.
| chewbacha wrote:
| My gut is to assume that aluminum isn't as viable because it
| does _not_ oxidize as readily as iron does.
| SV_BubbleTime wrote:
| Aluminum definitely oxidizes extremely well. Most of the
| aluminum you come in constant with is oxidized intentionally
| (anodizing).
|
| It's just a ridiculously expensive metal to make.
|
| Look up how much alumina is minded all over the world, how
| it's shipped to Iceland for processing because of their cheap
| geothermal electricity, then shipped to China to processing,
| then shipped back around the world to final destination. It's
| crazy.
| samus wrote:
| Aluminium production is complex and might be less efficient per
| kilogram than iron production. Also, compared to iron there are
| no known processes to employ hydrogen, which can be had from
| green-ish sources, in aluminium production.
| Tade0 wrote:
| > "Places that have excess energy could make iron, and others can
| buy it. This way, you could commodify renewable energy so it can
| be globally distributed without the need for transmission lines.
| Metals can solve a big problem in the renewable energy
| transition: long-duration energy storage."
|
| My gut feeling is that transmission lines would still be cheaper.
| That being said long-term storage seems to be the value
| proposition here.
|
| In my corner of the world coal is still frequently used to heat
| homes during winter. A single house uses around 4-6 tonnes of the
| stuff each season. This heap of coal takes a significant amount
| of space.
|
| If my back of the napkin calculations are correct, the energy
| equivalent in iron dust would be half the volume. Of course
| there's the issue of weight - about 5x that of coal, but perhaps
| the cost of moving all that iron could be somewhat mitigated by
| having a rust reprocessing plant in the neighbourhood.
| elil17 wrote:
| Transmission is expensive if you're running a line to somewhere
| without a lot of demand. Something like this could be a
| relevant solution for anything in remote locations.
| chasil wrote:
| "Altiro gets around this problem by adding a little natural gas
| to ignite the iron powder when the boiler first starts up."
|
| You will also need a very specialized furnace, and supplies of
| CH4.
| samus wrote:
| The demand for natural gas is probably minuscule compared to
| the total heat output of a burning cycle. Also, thanks to the
| war in Ukraine, demand for natural gas might decline in the
| long term if European countries switch to alternative,
| hopefully greener, energy sources.
| Tade0 wrote:
| I suppose it's not more complicated than an LPG system in a
| car, which fires up on gasoline and switches to gas only
| after warm-up.
|
| My Uber today was a Corolla hybrid and at one point I heard
| the telltale clunk of the LPG system engaging. Apparently you
| can have that on a hybrid as well.
| ben_w wrote:
| Yeah.
|
| Article says energy density of 11.3 kWh/litre.
|
| WolframAlpha says using that for all global electricity for a
| day is 33e9 kg iron:
| http://www.wolframalpha.com/input/?i=2%20TW%20%2A%201%20day%...
|
| Some estimates I did a while back and then wrote up nicely with
| ChatGPT said a global power grid would use about x100 that much
| iron: https://github.com/BenWheatley/Studies-of-
| AI/blob/main/Globa...
|
| So the cut off between them is that if you use this for more
| than about four (/eight) months, the grid was cheaper.
|
| That said, while I personally love the idea of a global grid,
| geopolitics rather than technical merit is likely to be the
| dominant constraint for any solution, as everything[0] is cheap
| enough that cost doesn't matter.
|
| Also, possibly still useful for shipping? Possibly? I assume
| they'd prefer synthetic oil, but I don't claim any real
| knowledge, that's just my uninformed guess.
|
| [0] Well, almost everything -- concrete-based gravity batteries
| produce too much CO2 so they're expensive with current
| production methods just in a non-monetary sense, and antimatter
| production is so inefficient it's not viable, but those are the
| only two exceptions I know about.
| fnordpiglet wrote:
| Iceland has absurd amounts of spare energy. So they bring in
| ships full of bauxite and refine it into aluminum blocks then
| load it back on the ship. Aluminum is refined by electrolysis,
| so it's a perfect way to export their excess electricity.
|
| That's stocking btw that it takes 4 tons of coal per year per
| house. That's an absurd amount.
| euroderf wrote:
| I'm a serious PITA about recycling aluminum. I have this
| mental image of vast quantities of bauxite and energy being
| tossed out whenever an aluminum container (or bit of foil) is
| not recycled. But I don't have any firm numbers.
| Tagbert wrote:
| According to:
| https://www.lehighcounty.org/Departments/Solid-waste-
| managem....
|
| "About 65 % of America's aluminum is currently recycled."
| That's pretty good. Much better than most materials.
| euroderf wrote:
| A national can deposit mandate might help eh.
| caseyohara wrote:
| It's not that absurd. One ton of coal produces ~25 million
| BTUs. That's about the same output as a cord of oak or
| hickory, which weigh about 2 tons per cord. And most people
| that heat their home exclusively by burning wood use about
| 5-6 cords per year.
| bioemerl wrote:
| What if the place with excess energy is America in the place
| was not enough is Europe?
| [deleted]
| _hypx wrote:
| Pipelines of liquid or gaseous fuels is pretty much always
| going to be the cheapest solution for energy transmission. This
| fact will inevitably lead to people investing in some kind of
| green chemical. If not hydrogen, then likely something made
| from hydrogen like ammonia or methanol.
|
| It's not actually clear if transmission lines are cheaper.
| Ships and trains can carry a lot of mass. For an energy dense
| fuel, this can be cheaper. Then again, this idea needs you to
| carry things in both directions, both the iron and the iron
| oxide. That may doom this idea to being too expensive.
| lll-o-lll wrote:
| How many posts about hydrogen being the best and only hope
| have you made here?
|
| I can't recall it all now, but my understanding was that if
| you take the entire chain from production to storage to
| consumption of hydrogen, it's pretty much an unworkable
| engineering problem. "The closest thing to a vacuum, other
| than a vacuum" was one memorable quote. Happy to be shown to
| be wrong.
| _hypx wrote:
| Because it is instrumental to solving to climate change.
| The better question is why are people unwilling to take the
| problem seriously?
|
| Your understanding is the result of years of FUD against
| it. People really need to understand that they have been
| lied to repeatedly on this subject. If you have a basic
| grasp of engineering, you should understanding that it is
| literally made by running electricity through water. It is
| an incredible simple idea that you can even do at home. And
| since hydrogen is already being used in a vast number of
| industrial and chemical processes, it should be clear that
| there could not be any fundamental technical challenges
| that haven't been solved.
| torgian wrote:
| I mean, then you're gonna have dunces who try to run
| electricity through salt water. Which created a very bad
| gas that humans cannot breathe.
|
| The issue is you're going to need distilled water in
| order to create hydrogen particles.
| defrost wrote:
| What is this, 2019 ???
|
| _A membrane-based seawater electrolyser for hydrogen
| generation_ (2022) Here we propose a
| direct seawater electrolysis method for hydrogen
| production that radically addresses the side-reaction and
| corrosion problems. A demonstration system
| was stably operated at a current density of 250
| milliamperes per square centimetre for over 3,200 hours
| under practical application conditions without failure.
| This strategy realizes efficient, size-flexible and
| scalable direct seawater electrolysis in a way similar to
| freshwater splitting without a notable increase in
| operation cost, and has high potential for practical
| application.
|
| https://www.nature.com/articles/s41586-022-05379-5
| lll-o-lll wrote:
| Well, many years ago before I switched to software, I was
| an engineer in real life! Putting on the old dusty
| engineering cap, I have to say that your explanation
| there is so underwhelming as to make it hard to take you
| seriously. The information I have read on this has not
| been FUD. It's been careful analysis by actual engineers
| with experience in the field. Something being
| "technically possible" is completely different to
| something being "economically feasible". Sorry, if you
| want to make an argument, you're going to have to do
| better than that.
| _hypx wrote:
| Well even engineers can have seriously incorrect
| understanding of an issue, especially if it is many years
| out of date.
|
| You're argument seems to be based around economically
| feasibility, not technical issues, right? So then you
| will also agree that if green hydrogen radically dropped
| in cost, then you will agree that it _will_ become a
| viable solution? Furthermore there will be subsidies
| going on, that will accelerate the process.
|
| In fact, the problem might be that a combination of
| subsidies and cost reductions will drive the price to
| below $0/kg, causing market confusion:
|
| https://www.spglobal.com/commodityinsights/en/market-
| insight...
|
| That would be an interesting outcome and it will be
| interest to see how it ends up. But nevertheless, super-
| cheap green hydrogen should quickly refute the major
| arguments used against it. It is a process that mirrors
| what happened to wind and solar energy. They too have
| years of FUD followed by many skeptics who denied the
| possibility of cheap renewable energy. But that
| skepticism simply fell apart because basic economics
| overrule outdated opinions.
| lll-o-lll wrote:
| > You're argument seems to be based around economically
| feasibility, not technical issues, right?
|
| Economic feasibility due to _engineering_ problems. Just
| because something can be done in a lab does not mean it
| _can be done at scale_. As an example, Musk with his
| stupid hyper-loop. Sure it is _technically possible_ to
| evacuate a tube and send a vehicle through it at high
| speeds. It will never be _economically feasible_ ,
| however. Sometimes the engineers just have to say "not
| going to work" to an otherwise cool idea.
|
| It's not the cost of hydrogen production. It's the
| engineering problems that pervade the rest of the
| handling, storage and distribution of hydrogen that look
| to be insurmountable.
| _hypx wrote:
| > Economic feasibility due to _engineering_ problems.
|
| The question then becomes, _who 's actually saying this?_
| It's certainly not real engineers. In fact, real
| engineers have pointed out that it is much cheaper to
| distribute hydrogen than electricity:
|
| >BRINK: How do you move the hydrogen from the solar
| farms?
|
| > AD VAN WIJK: By pipeline. That's the interesting thing:
| It is about 10 times cheaper to transport energy by a
| hydrogen pipeline than by an electric cable. That makes
| it possible to transport electricity very cheaply from
| somewhere like North Africa to the demand centers in
| Europe, for example.
|
| https://www.brinknews.com/could-hydrogen-replace-the-
| need-fo...
|
| And all of this is happening under the auspices of
| effectively free hydrogen due to a combination of
| subsidies and cost reduction. This should really raise
| the question of how any of the alternative ideas are
| going to compete with this, not how whether this idea can
| work.
| lll-o-lll wrote:
| > The question then becomes, who's actually saying this?
| It's certainly not real engineers. In fact, real
| engineers have pointed out that it is much cheaper to
| distribute hydrogen than electricity:
|
| I struggle to understand why you would say this. Here is
| one example. Paul Martin is a Chemical Engineer (that's
| the right kind of engineering to talk about this topic).
| https://www.resilience.org/stories/2023-03-31/paul-
| martin-hy...
|
| If you actually take off the "hopium" goggles and
| critically evaluate the problems, I think the truth is
| the hydrogen solution is not only _unsolved_ it also
| probably can't _be solved_.
| _hypx wrote:
| Paul Martin is not a valid authority on this. He is a
| known anti-hydrogen skeptic and had made many nonsensical
| claims about hydrogen. The most notable is perhaps his
| limited understanding of how fuel cells work, and his
| claim that fuel cells can never dramatically exceed the
| efficiency of diesel engines.
|
| This is false, as fuel cells are electrochemical systems
| that do not follow Carnot's theorem. Which is to say that
| it is fully possible to build a fuel cell that greatly
| exceeds the efficiency of diesel engines.
|
| Not to mention that most of his claims are from some
| years ago, and are becoming obsolete even if they were
| true. He has not commented on (AFAIK) about the effects
| of subsidies nor admitted that costs are dropping
| rapidly. He just sounds like another anti-renewable
| skeptic similar to those that criticized wind and solar.
|
| It's worth mentioning that all of them are similar in a
| way: Old, retired or nearly retired, and usually coming
| from in the fossil fuel industry. And yes, Martin is from
| the fossil fuel industry, and has no experience with
| hydrogen beyond its existence as a feedstock for oil
| refining. He has never had any experience with modern
| hydrogen-related facilities, equipment and concepts.
|
| Engineers that actually do have experiences with those
| area do not agree with Paul Martin. So there are
| alternative viewpoints from knowledgeable people. You can
| look at recent statements by BMW and Bosch, including
| what their engineers have said. They are clearly
| believers of the idea:
|
| https://www.repairerdrivennews.com/2022/09/01/bmw-bosch-
| anno...
| lll-o-lll wrote:
| Your argument is now "older people are stupid?". The
| information is old and irrelevant? The article I linked
| was from this year.
|
| I just picked a critical engineer at random, but I can
| see I'm wasting my time here. _You_ are clearly not any
| kind of expert. _I_ am clearly not any kind of expert.
| This is just devolving into nothingness, and I'll leave
| it here.
| [deleted]
| _hypx wrote:
| You are clearly misrepresenting my point. Your authority
| is not really an authority for a bunch of reasons. One of
| which is how he is basically a retired petroleum engineer
| with very little understanding of the modern state of
| hydrogen. And yes, this usually implies an old person,
| something Arthur C. Clarke noticed in one of his writings
| about elderly scientists. And while your link is from
| this year, he's been saying the same thing for many years
| now without change. In fact, the only recent change in
| tone is his exacerbation, as billions of dollars are
| being invested anyways and he is upset about that.
|
| You are not picking a critical engineer at random. You
| picking basically one of the very few credible critics,
| and they're all basically known to the community. The
| rest of the engineering community in this sector are
| certainly not as skeptical. In fact, you completely
| ignored my link about engineers that are doing real work
| in this area.
|
| I asked previous about "who's actually saying this?" to
| the question of engineers that doubt hydrogen. And that
| question is still relevant, because outside of a tiny
| minority of scientists and engineers, most of whom are
| outdated and poorly informed, the rest are just armchair
| experts and random celebrities.
|
| So the point is that you are simply wrong about your
| understanding of the issue. The intellectual community
| fully accepts the possibility of hydrogen as a widespread
| fuel and a way to solve climate change.
| ehvatum wrote:
| > So the point is that you are simply wrong about your
| understanding of the issue. The intellectual community
| fully accepts the possibility of hydrogen as a widespread
| fuel and a way to solve climate change.
|
| That is terribly naive and wishful thinking, I'm afraid.
|
| For even the smallest-scale industrial applications,
| hydrogen is almost invariably produced on-site, near or
| within the manufacturing cell consuming it. Even if Linde
| charged nothing at all for hydrogen, electrolysis would
| still win: no 10kpsi (good lord) tank, no inevitable 1%
| loss per month of high-pressure hydrogen, no extra
| insurance premium.
|
| If you'd dealt with hydrogen in industry, you might
| appreciate the problems with it. The static electric
| discharge from fingertip to ground required to ignite
| hydrogen is barely perceptible, and a ridiculously low
| atmospheric hydrogen concentration will burn with a very
| hot flame invisible in daylight.
|
| The proposition of the public driving high-pressure
| hydrogen tanks around is brain-damaged. If you want fuel,
| you should make methanol from your hydrogen - for the
| same reasons that, if you want hydrogen, you already
| produce it from water or natural gas or propane.
|
| Hydrogen has been an excellent topic for boastful press
| releases by car companies, corrupt nations, and fossil
| fuel producers murderously determined to continue the
| status quo indefinitely. It's ideal for that, because
| there's no danger of practicality.
| _hypx wrote:
| Then you are repeating the same mistake as the other
| person: Who is your source? All of the stuff you said,
| which engineer or scientist is actually saying those
| things? And no, some well-known critic like Paul Martin
| doesn't count. Those are outmoded and outdated people,
| and are totally clueless about recent developments in the
| field.
|
| On the other hand, real engineers with real experience in
| the area are saying the exact opposite:
| https://www.repairerdrivennews.com/2022/09/01/bmw-bosch-
| anno...
|
| In reality, you are just repeating the claims of some
| random armchair expert. These days, those seem to be
| usually battery car fanatics. Though you still see the
| occasional pro-biofuel or pro-fossil fuel guy. Either
| way, it is coming from a totally unqualified person.
| coderenegade wrote:
| Methanol is a pretty decent storage medium for hydrogen,
| and can be made more efficiently than LH2. It actually
| stores more hydrogen than LH2 on a volumetric basis, and
| you can crack it at fairly low temperatures, so a hydrogen
| economy is probably going to happen regardless, it just
| won't be in the form of transporting gaseous hydrogen. We
| need methanol to make solvents and polymers, and to power
| cargo ships. We need ammonia for fertilizer. These two
| vectors will probably be the way we create and move
| hydrogen around. Methanol will probably pick up an
| additional use case as a fuel for trucks and cars, since
| alcohols are what you typically resort to for ICEs in the
| absence of fossil fuels, and methanol is both the simplest
| to make, and a very good fuel in its own right.
|
| Hydrogen itself is more likely to be used to store energy
| in salt caverns, which is a proven technology for decades
| now. Aside from storage for the above use cases, it's a
| workable fuel for gas turbines for backup power.
|
| This seems like the most likely outcome in my opinion.
| SmooL wrote:
| > My gut feeling is that transmission lines would still be
| cheaper
|
| Transmission lines are great for moving electricity, but only
| if there's demand for that electricity _right now_. Otherwise,
| you have to store it - which is a problem, because battery tech
| right now isn't great (or rather, it's not good enough for
| grid-scale requirements) . This iron powder could be thought of
| as a "battery". It might be harder to move than compared to a
| transmission line, but it's _stored_ energy and can be redeemed
| at a later time.
| rootusrootus wrote:
| > not good enough for grid-scale requirements
|
| Is that still true? Aren't there a number of very successful
| grid battery installations now? And given the steady decline
| in battery costs, it ought to just get better and better.
| dgacmu wrote:
| Batteries are amazing for short term supply / grid
| stabilization. They can supply massive current on very
| short notice. But the cost per kilowatt hour is still
| painfully high if we're talking about more than a handful
| of hours. Fortunately, it's still headed downward.
| xyzzyz wrote:
| There are successful grid battery installations, but as far
| as I know, there are no _grid-scale_ battery installations.
| Existing installations have really small capacity, and are
| only used for things like demand smoothing. The only energy
| storage solution deployed at scale is pumped hydro storage.
| gpm wrote:
| For anyone wondering
|
| List of pumped-storage hydroelectric power stations
| https://en.wikipedia.org/wiki/List_of_pumped-
| storage_hydroel...
|
| List of (non-hydro) energy storage power plants https://e
| n.wikipedia.org/wiki/List_of_energy_storage_power_p...
|
| Largest battery plants in particular: https://en.wikipedi
| a.org/wiki/Battery_storage_power_station#...
|
| "Really small capacity" here apparently means "roughly 4
| hours of discharging as fast as possible".
| bradknowles wrote:
| You can use those transmission lines to move the energy to a
| facility where it would then be stored.
|
| In fact, you have to use some sort of transmission lines to
| get energy to those locations, otherwise you have no way to
| get energy to or from them. Even if they have local power
| generation, you still have to use transmission lines to get
| that power out.
| hankman86 wrote:
| But isn't that the point of transmission lines - match supply
| and demand? Given a large enough region, there is going to be
| a place where renewable electricity can be produced. Case in
| point being offshore wind turbines where there are almost
| always strong winds to spin these. Moving this electricity to
| where it is consumed is a huge issue though. Existing power
| grids were created with centralised power stations in mind,
| which are usually located close to where the electricity will
| be needed.
| SmooL wrote:
| Yes, but transmission lines can only go so far, and you
| still lack the ability to arbitrage over time instead of
| just spatially. E.g. from a solar power POV, it's night
| everywhere in a given region at the same time.
| ben_w wrote:
| What do you believe the limits are to transmission lines?
| DennisP wrote:
| In the US we're especially bad at building new long-
| distance transmission. Some projects have languished for
| decades.
|
| There are probably other places where it's difficult to get
| that large-enough region, for geographic or geopolitical
| reasons.
| cogman10 wrote:
| > or rather, it's not good enough for grid-scale requirements
|
| I disagree with this point. LFP batteries are cheap, high
| density, and have huge cycle life. The big drawback of LFPs
| is manufacturing is just starting to ramp up on them. That
| is, they aren't available.
|
| LFPs just came out of patent protection last year and you are
| already starting to see them everywhere. The biggest problem
| with LFPs today is demand is outstripping supply.
| baybal2 wrote:
| [dead]
| concordDance wrote:
| Got any numbers here?
| cogman10 wrote:
| For LFPs at the moment we are looking at 100->150/kwh of
| storage. [1]
|
| Cycle life is around 3000->10000 cycles depending on how
| deep the cycles are (more shallow cycles, longer battery
| life). [2]
|
| Note: Cycle life is about how long it takes for a battery
| to lose 20% of it's capacity. That doesn't mean you can't
| still use it.
|
| [1] https://www.fastmarkets.com/insights/the-ev-battery-
| chemistr...
|
| [2] https://www.powertechsystems.eu/home/tech-
| corner/lithium-iro...
| Retric wrote:
| They're cheap enough for EV's, but the big number here is
| you can get 10,000+ charge/discharge cycles. Predictions
| are near term ~2c/kWh grid storage looks realistic which
| completely changes the economics of the electricity grid.
| (As in whatever you pay for the electricity to charge the
| batteries you need to charge 2 more cents/kWh at
| discharge to break even.)
|
| Pair with renewables and not only is nuclear and coal
| looking obsolete but even natural gas is uneconomical at
| current prices. Of course the economy reacts as you start
| to bring this stuff online which means wholesale natural
| gas prices could fall quite a bit etc. You also need
| enough wind/solar/hydro to actually charge the batteries,
| but that doesn't seem to be an issue either.
| ac29 wrote:
| Assuming LFP means Lithium Iron Phosphate (LiFePO4)?
|
| Not sure how to reconcile "they aren't available" with
| "starting to see them everywhere".
|
| They're great batteries (especially compared to lead acid)
| and at least in small quantities, they have been widely
| available for years.
| Wingy wrote:
| I read it as "they aren't available right now, but they
| will be very soon."
| coryrc wrote:
| If we're using renewables, we need seasonal shifting, so
| cycle life doesn't matter at one cycle per year.
|
| You could build nuclear to supply your winter power, but
| then you're overbuilt for summer and don't need any
| renewable. Or you could store heat directly in the ground
| like that Alberta pilot project, heat collectors on the
| roofs all summer drive the heat underground, pump it back
| out all winter.
|
| Or our current plan, pretend to be "green" by spending
| money on solar while increasing coal usage and no feasible
| plan to replace space heating.
| bryanlarsen wrote:
| We don't need seasonal storage. The sun still shines in
| the winter, unless you're in the Arctic circle. We can
| use over building, production diversity, interconnection
| and short term storage instead. Or just use natgas
| peakers for the last 1% and call a 99% solution good
| enough.
|
| If we had reasonably priced seasonal storage we'd use it,
| but we don't need it.
| ben_w wrote:
| > Or just use natgas peakers for the last 1% and call a
| 99% solution good enough.
|
| Sadly, no. Given how long the CO2 stays in the air,
| anything less than 99.9% over all emissions from all
| nations -- and that also includes cement and iron
| chemistry leading directly to CO2, cattle biochemistry
| leading directly to methane, etc. -- then we're not
| pushing hard enough.
|
| Natural gas is great as a way to buy time, but we can't
| let it be more than a rounding error in the ultimate
| ensemble... well, not unless there's corresponding CO2
| capture.
| coryrc wrote:
| In winter cloudy conditions solar PV produces 10-15%
| power. Assuming some hydro storage, that's 4x overbuild.
| Not cost effective.
|
| Europe all gets winter at the same time. If you've got a
| cold snap for three weeks with low wind, the only plan is
| reliance on massive fossil fuel backup. The cost of
| keeping that capacity for only using a week a year isn't
| priced into solar either.
|
| The CO2-intensity of electricity generation in France
| stood at around 57 CO2/kWh in 2020 (source: Statista). In
| Germany, the electricity mix at the same time had a
| CO2-intensity of 366g CO2/kWh, which was more than six
| times higher
|
| But yeah Germany's approach is really working!
| rbanffy wrote:
| > In winter cloudy conditions solar PV produces 10-15%
| power
|
| Depends on the latitude and these numbers seem to be for
| very high ones close to the polar circles.
|
| > Not cost effective.
|
| Are we pricing in the societal collapse due to climate
| change? I'd suspect a 4x overbuild would be quite cheap
| against that.
|
| OTOH, keeping some natgas capacity for when a freakish
| cold snap with no wind hits seems kind of OK.
| burmanm wrote:
| > Depends on the latitude and these numbers seem to be
| for very high ones close to the polar circles.
|
| No, those values are far from polar circle. I'm guessing
| closer to central Europe, since for example in Finland
| the PV produces 0% during the winter months.
|
| 10-15% would be insane to get here, but there simply
| isn't any energy in the sun (and closer to the polar
| circle you get - there's no sun at all during winter) and
| the panels are often covered in snow in any case. And I'm
| not even talking about cloudy days now, but "sunny" ones.
|
| March/October are already approaching those 10-15%
| levels. Nov-Feb is closer to 0% in most of the Finland.
| ben_w wrote:
| Finland (the south of it anyway) has about a gigawatt of
| HVDC lines connecting it to other countries, about
| 200W/capita.
| DennisP wrote:
| GP is clearly talking about cost-effectiveness compared
| to other solutions, such as France's approach and
| seasonal storage.
| wongarsu wrote:
| > "You can think of iron fuel as a clean, recyclable coal," says
| Bergthorson.
|
| I was under the impression that basically all naturally found
| iron is in the form of iron oxide. Which means you first have to
| put in energy to reduce it to pure iron, to then burn it and turn
| it back to iron oxide. That's much closer to what a battery does,
| or hydrogen, than it is to coal.
|
| I imagine it's still useful in many applications since hydrogen
| is a pain to store and transport.
| hankman86 wrote:
| Or you just use the iron to build more towers for wind turbines.
| Or transmission lines to send renewable electricity to where it
| is needed.
| samus wrote:
| There is no shortage of iron, while this is another way to make
| usage of abundant renewable energy. Especially when at the
| destination actually heat is required. Apart from that, neither
| wind turbines nor more transmission lines help with the problem
| of making excess energy available for _future_ use.
| mrguyorama wrote:
| Using electricity to run a heat pump will beat combustion in
| efficiency, and that only becomes way more true when the
| energy source starts as electricity being sunk into creating
| a synthetic fuel.
| samus wrote:
| While that is probably true, the problem still exists that
| renewables produce a lot of electricity when there is not
| enough demand for it. Iron combustion is a solution for
| that problem.
| jokoon wrote:
| At that rate, there should be an encyclopedia dedicated to all
| projects that can be described as greenwashing.
|
| I think it's a new strategy to "drown the fish", by flooding the
| media with "green" technologies just to pretend to say "we heard
| you, we are going to change the world with green new things" only
| to save more time until everybody realize each of those new
| projects are just not viable. The air travel sector seems to be
| rife with this.
|
| Who could have guessed that snake oil could work in something as
| serious as the energy sector, I'm really surprised it's getting
| so low.
|
| I'm going to be brutally honest, but you even hear people from
| first world countries playing the poverty card when you tell them
| they should stop driving alone in a 1 ton vehicle, and it seems
| sobriety and de-growth will have to convince those people that
| fossil fuels are a privilege, not a right.
|
| I can bet that we are going to see people sabotaging cars, gas
| stations and refineries pretty soon if nothing is done. Greta
| Thunberg will be 25 soon and a whole generation will not tolerate
| more lies.
| Slava_Propanei wrote:
| [dead]
| elihu wrote:
| 1 ton vehicles would actually be an improvement on the status
| quo, at least in the U.S. where a "small" car is usually more
| like 3,000 to 4,000 pounds.
|
| Also, if self driving becomes wide-spread and successful, we're
| going to start seeing a lot of zero-occupant cars on the road,
| most likely bringing the average vehicle occupancy below 1.
| jokoon wrote:
| > most likely bringing the average vehicle occupancy below 1.
|
| That would quite hilarious and horrific at the same time
| Animats wrote:
| Yes. See "blue hydrogen", "grey hydrogen" (from natural gas),
| "black hydrogen" (from coal), "turquoise hydrogen" (from
| methane)...[1]
|
| [1] https://www.weforum.org/agenda/2021/07/clean-energy-green-
| hy...
| unwind wrote:
| Okay, but it would be more helpful if you provided some actual
| arguments against the technology.
| cyberax wrote:
| It's another "use energy/hydrogen to create a fuel"
| technology.
|
| This one creates a very inconvenient fuel: iron powder. It
| can't be efficiently piped, and it needs some very strange
| technology to make it burn in controlled conditions. And you
| cannot use it for gas turbines or piston-based engines.
|
| At this point, if you have hydrogen, you can just use it to
| produce methane that has none of these problems. Or maybe
| ammonia if we ever get catalysts working at mild conditions.
| concordDance wrote:
| While it's very true that greenwashing is a thing, bans on
| fossil fuels are not the right approach. You need sin taxes
| that account for the cost of the externalities instead. A CO2
| tax is sensible, "degrowth" is a horrific thing that will kill
| billions.
| nyc_data_geek1 wrote:
| Done correctly, degrowth need not lead to billions of deaths.
| We desperately need to restructure our economic systems and
| societies to account for the reality that infinite economic
| growth on a finite world is not possible, realistic or
| desirable. If we do so, we can minimize the bleeding.
|
| If we fail to, billions will die on hothouse Earth
| regardless.
| Slava_Propanei wrote:
| [dead]
| mjan22640 wrote:
| Flywheel energy storage
| CoastalCoder wrote:
| It would be fun if our next major technology stage is the "iron
| age".
| MagicMoonlight wrote:
| Comparing petrol with iron based on volume rather than weight
| seems highly misleading. I'm assuming that actual energy density
| is much worse with iron right?
| obblekk wrote:
| > 0.3% of the Iron-oxide becomes nanoparticles which cannot be
| converted back into Iron.
|
| At that rate, 50% of the initial iron will be gone in 333 cycles
| of iron -> iron oxide -> iron.
|
| This a hard type of energy source to reason about:
|
| 1. It's not a pure fuel and acts like a battery most of the time,
| but it's also not renewable
|
| 2. Iron is extremely abundant on Earth, but it requires mining
| and processing to extract
|
| 3. Iron oxide in nanoparticle size would likely be a pollutant
| and hazardous to human health, not something that will break down
| quickly and harmlessly.
|
| The high fuel density and low explosiveness may make it a good
| use case in some niches, but I imagine it's actually more
| scalable and healthy to burn jet fuel and reproduce it from
| renewable powered carbon capture, where density is needed.
| umvi wrote:
| > The nanoparticles are not emitted in the atmosphere but
| captured in a HEPA filter.
|
| If that's true, your point #3 is moot. And if the nano
| particles can be captured by a filter, maybe we could design
| filters specifically for iron oxide nano particles that would
| allow the nano particles to be extracted
|
| > but I imagine it's actually more scalable and healthy to burn
| jet fuel and reproduce it from renewable powered carbon
| capture, where density is needed.
|
| You're saying capture carbon from CO2 and turn it into
| kerosene? I tried googling around and everywhere I look it
| seems like this is currently _way_ more difficult than
| renewable iron fuel (https://www.planet.veolia.com/en/how-
| produce-kerosene-co2).
| a3w wrote:
| Cherry-picking the fuel for jets example makes sense, since
| somehow we don't expect aviation to transition completely to
| airscrews.
|
| As for the disposal of HEPA filteres loaded with air-stable
| inorganics, that still is pollution, only the kind of waste
| you store safely, and if not give people cancer, but highly
| localized so.
| jerf wrote:
| To a first approximation, Earth is a big ball of iron, so
| losing 50% of the iron in 333 cycles doesn't seem like that big
| a deal. Getting more iron is an energy issue rather than an
| availability issue.
|
| I'm also somewhat concerned about the nanoparticle's effect on
| living things. It is likely that it is only a question of local
| exposure, as in general once they get out they should still
| rust in some relatively short period of time, and as Earth is
| the aforementioned big ball of iron, a bit of rust in the
| environment is quite unlikely to hurt anything because if it
| could hurt a thing that thing would already be dead, but
| locally nanoparticles would be something weird and I could see
| breathing them could be problematic. It is also entirely
| possible that it is safe up to surprisingly absurd levels too
| (your body is familiar with iron, and while there are toxic
| doses of iron you're not getting to them with nanoparticle
| exposure any time soon), it would just be something that would
| need some study.
| nick-of-time wrote:
| > To a first approximation, Earth is a big ball of iron
|
| This is a totally useless thing to say unless you have secret
| technology for core mining.
| marcosdumay wrote:
| > once they get out they should still rust in some relatively
| short period of time
|
| Nanoparticles of iron _oxide_ are already rust.
|
| There is certainly some inorganic phenomenon that will turn
| it into normal, aggregated rust. It probably requires water
| and some time.
|
| But those particles sound like the kind of thing that will
| stay for years on the atmosphere, and contaminate every
| living thing. And yeah, they are probably safe in some
| surprisingly large amount, so whatever direction it goes, we
| will only know after we start doing it.
| mrguyorama wrote:
| Maybe then we could stop putting iron filings in children's
| cereal as a supplement.
| onlyrealcuzzo wrote:
| > so losing 50% of the iron in 333 cycles doesn't seem like
| that big a deal.
|
| Where does the Iron go??? It's not like Fission or Fusion is
| happening, right?!
| DennisP wrote:
| Per the article, it goes into the HEPA filter. After that,
| recover it or dispose of it as you see fit.
| rsaesha wrote:
| >Earth is a big ball of iron.
|
| No it's not.
|
| Inside the crust both Si and Al are more common.
|
| There is plenty of Fe, which is all in oxide form. Mining and
| processing required.
| dredmorbius wrote:
| Shrug.
|
| Iron is _abundant_ on Earth, including within the crust,
| where it 's the fourth most abundant element (after Oxygen,
| silicon, and aluminium), roughly 5% by mass. And yes,
| considerably more prevalent in the core. Iron and oxygen
| account for roughly 32% of Earth's total mass, each, the
| largest proportion of any element.
|
| <https://en.wikipedia.org/wiki/Earth_mass>
|
| Sure, not _as_ abundant as silicates. But nowhere near as
| rare as gold, platinum, and rhodium. Or even copper,
| silver, or lead.
|
| <https://en.wikipedia.org/wiki/Abundance_of_elements_in_Ear
| th...>
|
| There's even a fair bit of it flowing though your veins and
| arteries right now.
|
| And yes, the major ore deposits are _old_. Most are BIFs
| (banded iron formations), and date to 1 bya or 3.5 bya,
| laid down by early oceanic algae for the most part.
|
| Sometimes it's more than fine to allow a slight
| exaggeration to pass without litigating it to death.
| rsaesha wrote:
| Let's be reasonable here, mantle and nucleus iron don't
| matter to this analysis.
|
| Crust iron is all oxide. Fe at 5% average. In some
| locations obviously more concentrated up to 90% ore. Not
| all sites are viable for mining, and this is very
| important to understand. Just because there is plenty of
| iron out there doesn't mean all of it is commercial
| grade.
|
| This means energy input to turn iron oxide into iron,
| which the article claims could be used as fuel and/or
| long term energy storage.
|
| -Fuel I don't believe for a second.
|
| -Energy storage it's a maybe. It needs to commercially
| beat plenty of options. Which to me seems unlikely since
| the path still includes heat and steam engine which would
| incurr at a cicle loss of at least 50%. And this being
| conservative etc. Would mean a steam engine operated in a
| very narrow power band - which would mean a baselevel
| powerplant not a peaker powerplant. And didn't yet
| consider other possible losses, as for one, the Fe
| degradation over time. Energy cycles that count on heat
| and engine are wasteful. Could this waste be compensated
| by a much cheaper capex and/or opex relative to Li or
| similar batteries? That's a big Maybe.
|
| I myself want to believe there is a solution to
| renewables intermittency. But on this one in particular,
| I'm quite bearish for the reasons above.
| proto-n wrote:
| Is iron oxide magnetic in nanoparticle size? Because if it is,
| then we can probably very efficiently filter it before
| releasing it into the atmosphere.
| idiotsecant wrote:
| Even if it isn't we are very good at filtering materials from
| exhaust gasses. Something like a wet electrostatic
| precipitator is probably overkill, but would do the job
| without having to care about magnetic properties.
| nabla9 wrote:
| Traditional methods or their combination: wet scrubber,
| electrostatic precipitator or bag filters will do the job.
| juujian wrote:
| The article mentions a HEPA filter.
| sudhirj wrote:
| That's still a mess, if the particles are magnetic a magnet
| will be a way cleaner and more effective filter.
| thsksbd wrote:
| iron oxide magnetic properties depend on its oxidation state,
| temperature and particle size.
| 13of40 wrote:
| Not sure why this is dead, but AFAIK magnetism in iron and
| steel is dependent on "domains" of iron molecules that are
| aligned in a crystal structure so the magnetic effect isn't
| just scattered to all directions. That's why some kinds of
| stainless steel aren't magnetic - the adulturant elements
| break up the crystal structure. In this case I think the
| question would be whether these particles are big enough to
| form a "domain" and become magnetic.
| thsksbd wrote:
| [dead]
| pixl97 wrote:
| If the output is iron oxide, no it is only very very
| weakly magnetic.
| jjk166 wrote:
| The nanoparticles can't be converted back to iron in this
| process, but they can still be turned back into iron by other
| processes. No system is truly closed loop, but this is more
| closed loop than any other energy-to-fuel system.
|
| You need to extract the feedstocks for any energy-to-fuel
| system. Iron is cheap and simple to extract, compared to say
| carbon from the atmosphere.
|
| The nanoparticles do not get released to the environment.
| Emissions from burning carbon based fuels also include
| pollutants that are hazardous to human health.
| idiotsecant wrote:
| > Emissions from burning carbon based fuels also include
| pollutants that are hazardous to human health.
|
| Which _do_ get released into the environment in quite large
| quantities!
| mirekrusin wrote:
| Can't you just make pulsating/spinning magnet to capture it?
| juujian wrote:
| Might be possible to create a completely closed system to
| address the loss?
|
| I am more concerned/confused by the fact that they use hydrogen
| to reduce the iron. That seems like a very convoluted process,
| why not use the hydrogen generate heat instead? Yes, it has
| much lower density, but it has advantages to make up for it,
| for instance the fact that you don't need to worry about
| evaporation, leakage, filters, all that at all.
| PaulHoule wrote:
| Hydrogen is devilishly hard to transport and store. Hydrogen
| packs a lot of energy per gram, but the density is so low.
| You need a huge tank if you compress it as a gas, you can
| liquefy it but the density is still not great, it takes a lot
| of energy, and you have to deal with this:
|
| https://en.wikipedia.org/wiki/Spin_isomers_of_hydrogen
|
| freshly liquefied hydrogen contains a lot of stored energy in
| that form which will be released over time and cause quite a
| bit to vaporize, for long term storage you have to release
| that energy.
|
| Thus people have looked at all sorts of schemes for storing
| hydrogen such as absorbing it in metals like palladium, metal
| hydrides, chemical carriers such as ammonia, methane, etc.
| kaliszad wrote:
| Sodium would be a much better proposition. With NaOH, you
| can create a closed cycle. The electrolysis of NaOH is the
| well known Castner process, a consumable metal anode fuel
| cell with sodium is also well known (expired Patent:
| US3730776A by Lockheed) More details and overlap with other
| approaches: https://orgpad.com/s/5BfLP-cxj-7
|
| Sodium has higher energy density (3.5 kWh/L) than liquid
| hydrogen, there is no energy needed to store it and no
| catalyst is needed for the fuel cell because sodium is so
| reactive with water. The fuel cell is rather easy to
| construct (I know somebody, who has done it in a garage).
| NaOH solution is very caustic but also neutralizes well
| naturally without long term effects at least in comparison
| to crude oil that seems to be the better proposition. And
| of course sodium is everywhere, where NaCl - table salt is.
| cmrdporcupine wrote:
| _"it's more efficient to produce iron from hydrogen gas than to
| produce liquid hydrogen. So iron powder as fuel is more expensive
| than gaseous hydrogen but cheaper to produce and move across the
| oceans than liquid hydrogen."_
|
| He's saying liquid _hydrogen_ , but I gotta wonder if the the
| real story here is an attempt to deal with moving the energy in
| _natural gas_ , since the liquified natural gas story is so
| shitty (expensive facilities, etc.) and pipelines are politically
| and logistically difficult.
|
| I would not be surprised to see this turned into a "burn/process
| natural gas (in North America etc) to produce the iron 'fuel'.
| Ship the iron by train or boat & skip building pipelines and
| tankers and LNG facilities." Which gets us no further on the
| climate change front, but answers certain current European (esp
| German) ... political / economic ... problems.
| elcritch wrote:
| Interesting, one benefit of such infrastructure would be that
| it could transition smoothly to using renewables. I believe
| it's possible to extract "Grey" hydrogen from LPG so it might
| not require burning, though it'd still release co2.
| SamPatt wrote:
| Requiring natural gas to work makes me a bit skeptical. They
| don't indicate how significant the nat gas component is, but if
| prices are low, it will be much simpler and cheaper to just use
| the gas itself.
| FrustratedMonky wrote:
| Doesn't this seem like we are just going to use up iron supplies.
| Iron would then become a used up commodity and drive up prices.
| Just like when Corn was used for ethanol, the side effect was
| driving up corn prices, and raising food prices. This could use
| up Iron, and then impact a ton of stuff.
|
| EDIT
|
| Missed this: "This can later be reduced--that is, the oxygen can
| be stripped away--back into iron powder. "You can think of iron
| fuel as a clean, recyclable coal," says Bergthorson."
|
| So guess it's all good.
| RajT88 wrote:
| The iron mining biz would probably expand, pushing prices down.
|
| Iron is just everywhere. I can go out in my back yard and find
| rocks which contain ore.
| bioemerl wrote:
| Iron is one of the most abundant elements on earth, but also we
| aren't going to be burning it like we do fuels now. Instead we
| would produce pure iron using green power and oxidize it back
| to it's natural state for energy in a cycle.
|
| Imagine loading an iron rod into your car, driving for a while,
| and then when you get into the gas station you dump a pile of
| rust off and buy a fresh iron bar.
| neolefty wrote:
| Some societal implications:
|
| * Kids playing with iron filings sounds a lot safer than kids
| playing with gasoline. "Don't leave your magnets in the fuel
| tank; it clogs up the lines!"
|
| * The gasoline party scene in Zoolander would need to be
| reconsidered.
| Arubis wrote:
| If we have to pick a natural resource to exploit for fuel, iron
| is a good choice:
| https://en.wikipedia.org/wiki/Abundance_of_the_chemical_elem...
| GlibMonkeyDeath wrote:
| Sounds like one of the least efficient energy storage ideas I've
| heard in a long time, I wonder how this is getting funded? Hmm,
| let's check to see who is behind this...the founding professor
| https://www.tue.nl/en/research/researchers/philip-de-goey/ is a
| fellow/awardee of the Combustion Institute, gets funding from
| ERC, etc. OK, so I guess all that European taxpayer money won't
| spend itself, and if you have a hammer blah blah nails...
|
| Meanwhile, stationary class (i.e. relatively poor energy density)
| iron air batteries are making commercial progress. https://pv-
| magazine-usa.com/2023/06/12/form-energy-to-deploy...
| volkl48 wrote:
| > Meanwhile, stationary class (i.e. relatively poor energy
| density) iron air batteries are making commercial progress.
| https://pv-magazine-usa.com/2023/06/12/form-energy-to-deploy...
|
| Also seems worth mentioning ESS. https://essinc.com/
|
| They're a bit further along (scaling up from low-volume
| production, some installs in the wild) with a different
| approach to the use of iron (flow batteries).
| scythe wrote:
| ESS should not be mentioned except as an example of how prone
| the green news cycle is to fraud. As I detailed last year,
| their claims are highly dubious:
|
| https://news.ycombinator.com/item?id=31430227
|
| (previously I misspelled the last name of Sri Narayanan as
| "Narayan", for which I belatedly apologize)
|
| And that prediction was substantiated when they were subject
| to a class-action shareholder lawsuit in February involving a
| fabricated customer which was actually a subsidiary:
|
| https://www.bloomberg.com/press-releases/2023-03-10/the-
| law-...
|
| The other shoe has yet to drop, but I suggest that any
| battery company without publications should be considered
| with appropriate salinity.
| Animats wrote:
| Yes, this is a strange approach. Separate iron from iron oxide,
| which is energy intensive. That's what blast furnaces did, or
| do, and it's a messy and energy-intensive process. Burn iron to
| get heat and iron oxide. Repeat.
|
| Are there numbers on the energy efficiency and costs of this
| process? This seems very strange. Batteries are above 90%
| round-trip efficiency now. This has to be lower.
| chasil wrote:
| According to the source below, aluminum has higher energy
| density than iron (23.5kWh/L versus 16.7kWh/L).
|
| The entry for iron in the link below is also higher than the
| iron energy density reported in the parent link (11/3 kWh/L).
|
| https://onlinelibrary.wiley.com/doi/full/10.1002/ente.202000.
| ..
|
| Of course, aluminum used in this way is the classic thermite
| reaction; I conjecture that the iron reaction is also.
|
| https://en.wikipedia.org/wiki/Thermite
| imtringued wrote:
| Then you haven't heard of energy vault then.
| thescriptkiddie wrote:
| > Iron oxide can also be reduced to iron using hydrogen
|
| > Altiro gets around this problem by adding a little natural gas
|
| This is transparently just green washing from the fossil fuel
| industry. There is no way that this will be an efficient energy
| storage mechanism and it definitely won't be carbon neutral.
| Developing cost-effective methods to produce steel from iron ore
| without the use of coke (coal) is important, but if you want to
| do that just do that.
| samus wrote:
| The natural gas is used to help starting and stabilizing the
| flame. Actual use of natural gas is probably negligible to the
| total output of the process.
| scythe wrote:
| Similar proposals have been made previously, particularly for
| boron, which has ten times the energy density of iron, and yet
| similar low combustibility:
|
| http://www.eagle.ca/~gcowan/boron_blast.html
| bbojan wrote:
| The elephant in the room are, as always, nitrous oxides (NOx).
|
| Whenever you burn something in a nitrogen atmosphere, NOx are
| created. They contribute to acid rain and the formation of smog,
| and are a trigger for asthma.
| samus wrote:
| While certainly being an issue, they are a far smaller problem
| than emissions of greenhouse gases by fossil power sources. It
| is a greenhouse gas itself, but most human emissions come from
| agriculture. Moreover, there are technologies to reduce the
| emission of NOx'es from burning processes.
| rcme wrote:
| Is iron oxide really that much more volumous than iron? In terms
| of capturing the iron oxide, why couldn't this be run in a sealed
| container with a valve that allows oxygen in? This doesn't work
| for hydrocarbons because the volume of CO2 is orders of magnitude
| greater than the volume of fuel, but does iron oxide have the
| same issue?
| MauranKilom wrote:
| I vaguely remember that continuous processes are strongly
| preferred over batch processes. Especially for such things as
| "provide energy".
| rfreytag wrote:
| I assume they are using renewable energy to reduce naturally-
| occurring iron oxide.
|
| When the iron is burnt are they going to do with pure oxygen?
| Otherwise they'll get pollutants like nitrogen dioxide, possibly
| ozone. And the 0.5% not burnt will also become a pollutant unless
| carefully removed in some smokestack scrubber.
|
| Or is this 'burning' to occur some kind of iron fuel cell? How
| would they liquidize the iron which is quite heavy?
|
| Lastly, iron is heavy. Moving reduced iron could be expensive and
| dangerous.
|
| Still, if sufficiently close to the renewable source this could
| provide much needed load leveling for intermittent sources.
| samus wrote:
| The article assumes the viability of a hydrogen-driven process
| to reduce the iron. The intention is to establish a circular
| economy of reducing iron oxidized by burning it in the proposed
| fashion.
|
| The byproducts from burning iron are no more noxious than
| burning fossil fuels, possibly less so. Filtration technologies
| exist as well.
|
| Of course this technology would have to compete with other
| technologies to make use of excess renewable energy, like
| liquid hydrogen storage and transport (which it has several
| advantages over), iron-based battery technologies, or green-
| produced carbon-based fuels. I guess it makes the most sense in
| applications where heat instead of electricity is required.
| _hypx wrote:
| > Of course this technology would have to compete with other
| technologies to make use of excess renewable energy, like
| liquid hydrogen storage and transport (which it has several
| advantages over), iron-based battery technologies, or green-
| produced carbon-based fuels. I guess it makes the most sense
| in applications where heat instead of electricity is
| required.
|
| I'm going to come out and say those competing technologies
| are vastly more plausible and viable.
| jacknews wrote:
| This makes no sense to me.
|
| Iron/steel production is one of the largest individual sources of
| co2 emissions and uses a lot of energy.
|
| And then to just burn it back into iron ore for energy - At best
| you'll only get back the energy you expended to refine it in the
| first place.
|
| Assuming they are burning scrap, it would surely be better to
| melt it down and recycle it as steel.
|
| As energy storage, it may well have more energy per liter than
| gasoline, but it weighs many times more. There are surely better
| options - even in the same category, eg aluminium?
| neolefty wrote:
| True, if we're getting it the traditional way.
|
| Fortunately, iron oxide can be reduced using hydrogen. In the
| article, they conclude that the system cost of shipping iron
| and iron oxide back and forth from an electrolysis facility
| (presumably from renewables) is lower than using hydrogen
| directly as a fuel.
| OrbitalPewPew wrote:
| Imagine thinking that a material stars can't use for fuel is one
| that makes sense as a "renewable energy source." These idiots
| need to go back and take undergraduate thermodynamics.
| skyechurch wrote:
| You can't extract energy from iron by nuclear fusion, which is
| how stars "burn" fuel, but this is a chemical process, Fe + O2
| => (some Fe&O compound) + energy.
| JoeAltmaier wrote:
| Confusing chemistry with fusion there.
| OrbitalPewPew wrote:
| [flagged]
| thsksbd wrote:
| Stars cant use Fe's _chemical_ energy because they 're too hot
| and the entropy of not being bound to O2 is too high. (And Fe
| is a trace element).
|
| No one is talking about using Fe as fuel in a nuclear reactor,
| or (even though the article muddles this) as a primary source
| of chemical energy.
|
| Its a battery. A heavy, big battery.
| __MatrixMan__ wrote:
| Skipping class to play with thermite was, in retrospect, an
| educationally sound decision.
| AlbertCory wrote:
| There's an experiment in here where Theodore Gray "burns" iron:
|
| https://www.youtube.com/watch?v=NMJtieqVUc4
|
| I hosted this. Getting permission from the Building department to
| have fire indoors was lotsa fun.
| __MatrixMan__ wrote:
| The lecture looks interesting, but if you want to skip to the
| burning stuff part: https://youtu.be/NMJtieqVUc4?t=2587
|
| I learned that stainless steel burns the hard way. You can use
| stainless steel scrubby pads as a heat sink to vaporize DMT in
| a contraption called "the machine". Naively, I thought steel
| wool would work instead of the scrubby pad. It doesn't. The
| fibers are too small and it ignites--pretty much exactly the
| opposite of what you want in a vape.
| AlbertCory wrote:
| Pro tip: do Show Transcript to skip around a YT video. Find
| the words you want, then click it.
| PaulHoule wrote:
| See also
| https://en.wikipedia.org/wiki/Chemical_looping_combustion
| scottLobster wrote:
| And just like articles about hydrogen, no mention of the
| extraction/distribution supply chains needed or the
| costs/emissions involved. Nope, just focus on our fancy (ZERO
| EMISSION) generator and ignore how the inputs are actually
| produced.
|
| It has the energy density of coal, only unlike coal it requires
| both mines as well as smelters/processing facilities to produce
| the iron powder. So this can only work if we build out twice the
| infrastructure that coal currently enjoys, with all the costs and
| emissions therein.
|
| I'm so tired of breathless scientific reporting of
| "breakthroughs" that ignores any and all economic context. Or,
| like this article, treats it as a side issue to be addressed with
| literally one sentence.
| credit_guy wrote:
| You are completely off.
|
| Why don't you try to do a Fermi estimate before voicing your
| concerns? Maybe things are not so bad.
|
| Steel is one of the few materials that humans produce in
| quantities exceeding one gigaton per year (the other ones are
| coal, oil, natural gas, concrete, and 4 agricultural crops,
| sugar cane, corn, rice and wheat).
|
| A lot of steel is recycled. It depends how you count, but
| between 60% and 90% of steel is recycled. Still, a lot of steel
| is produced out of iron ore each year.
|
| Currently to make a ton of steel out of ore we emit about 2.2
| tons of CO2, including upstream emissions[1, page 26]. If we
| make it from scrap steel, we only emit about 0.4 tons of CO2.
| It is projected that by 2050, both emissions will go to 0.1
| tons CO2-equivalent per ton of steel.
|
| The article mentions an energy density of 11.3 kWh per liter.
| Iron has a density of about 7.9 kg/l so, we're talking about
| 1.4 kWh per kilogram. From the article, we learn that the way
| the energy will be extracted from the iron powder is via
| burning in a regular thermal power plant. Good power plants now
| have efficiency of up to 64%, but let's says with the new fuel,
| they'll just produce 50%. The charging part will probably be
| more efficient, but let's say the round trip will be only 20%
| efficient. So what? This could still turn out to be much more
| economically efficient than hydrogen, or any other
| alternatives. If you want, we can do some estimates there too,
| but your concern was about emissions, not about profitability.
|
| Let's focus on emissions. Each time you burn one ton of iron
| powder, you generate (assuming 50% efficiency) about 0.7 MWh of
| electricity. In the US, on average, in order to produce that
| much electricity, you emit about 0.5 tons of CO2-equivalent,
| according to the EPA. If you charge and burn one ton of iron
| only 5 times, you come out ahead. But you will charge and burn
| it hundreds if not thousands of times. It's just iron, it's not
| a battery that degrades over time. It's iron powder, after each
| round trip, it's iron powder again.
|
| Each ton of iron powder can potentially reduce emissions by
| thousands of tons of CO2 equivalent. Each year all of humanity
| emits about 50 gigatons of CO2 equivalent, gross. The planet
| absorbs about half of that. A fraction of a gigaton of iron
| powder could help us get rid of all of our emissions.
|
| This thing here could be a revolution. Until now, I thought
| that our only economic way to store long time or transport long
| distance electricity is hydrogen. Iron powder solves so many
| problems with hydrogen.
|
| Feel free to criticize it, but don't simply be dismissive.
| Bring information to the table, so everyone here can appreciate
| it was worth their time reading your comment.
|
| [1] https://rmi.org/wp-
| content/uploads/2022/09/steel_emissions_r...
|
| [2] https://www.epa.gov/energy/greenhouse-gases-equivalencies-
| ca...
| VadimPR wrote:
| We are already using the most economically viable option. The
| trouble is that it's not sustainable long term. The solution
| then will not be the most economical one.
| scottLobster wrote:
| Right, but from an emissions standpoint this is a bad idea
| too. You not going to create an emission-free iron
| mine/processing supply chain any time soon. This just moves
| the emissions up the chain and would take decades to build
| out. It might be just as bad as coal in terms of emissions at
| the end of the day, and marginally better at best.
|
| Solar, Wind, more/better batteries and nuclear are our best
| paths forward if we want to take the immediate action we need
| to take. If crap like this gets traction we'll just have a
| greenwashed future where all the coal and natural gas plants
| will be gone, but global emissions will still be high and
| power will be many times more expensive. Maybe then people
| will start to do math.
|
| Back when I was in college the Environmental Science majors
| were a joke because the chemistry classes they took senior
| year were the same classes the Chemical Engineers took
| freshman year. I thought my university just had a crappy
| environmental science program, but after reading a number of
| articles like this one I'm thinking it might be a more
| pervasive issue.
| wolverine876 wrote:
| Then the issue is with the chemical engineers, who haven't
| learned the waste, counterproductiveness and foolishess of
| dismissing other ideas, viewpoints and people. It's a
| vicious cycle - it greatly limits their ability to learn
| what they don't already believe, or deal with challenges to
| their ideas. The only solution is to give no validity to
| such dismissals.
|
| I was taught that, in part, by a fed-up engineering
| professor.
| scottLobster wrote:
| Actually rejecting someone's perspective because they
| lack expertise in the thing they claim to be an expert in
| is a pretty smart thing to do. Particularly if you can
| explain why their perspective is wrong because you are in
| fact an expert and have superior knowledge.
|
| I would hope Environmental Scientists, who are
| purportedly concerned with things like ocean acidity,
| pollution, atmospheric makeup, etc would have the
| chemical knowledge necessary to understand what they're
| looking at. Apparently whoever designed their curriculum
| at my almamater thought it was unnecessary.
| wolverine876 wrote:
| > We are already using the most economically viable option.
|
| Arguably we always are doing that, by definition. Investment
| is spending money on current non-optimal returns in exchange
| for much greater returns later.
|
| If an investment had guaranteed success; if it had no flaws,
| then it would already have been made. There is nothing
| flawless in this world - not you or me, not Facebook or
| Messi, not oil or iron or renewables or nuclear.
| dv_dt wrote:
| Not really economically viable unless you narrowly focus on
| profits. For total direct and external costs (i.e. total
| societal costs) it's already nonviable.
| _hypx wrote:
| The second most economically viable option is basically going
| to be hydrogen in some way. Either made from renewables or
| nuclear power, possible natural sources if they exist in
| quantity. That is why you hear about it so much.
|
| But this fact causes large scale confusion on all sides. For
| those invested in the existing system, this is a threat. But
| for those who think it will be some other kind of green
| technology, this means admitting they were betting on the
| wrong horse the whole time.
| eddyzh wrote:
| It is not an energy source. It is a (battery) energy storage
| solution that can scale. Meant to support renewables use at
| night/ low sun/low wind periods. And not on hourly scale like
| normal batteries but on year scale on plant level.
|
| Like in an energy plant. That during the day when there Is
| surpluses they generate iron powder from ironoxide and cheap
| electricity. And when there is no surplus they burn the iron
| powder to irononoxid. And they can both be stored at unlimited
| scale on a heap.
| _hypx wrote:
| The problem is that that is the same idea that people are
| proposing with hydrogen energy storage systems. The
| difference is that hydrogen works a lot like natural gas. You
| can pipe it and fire up gas turbines with it. It is also
| useful as a chemical feedstock in many industrial processes.
| You can also use it to power vehicles, something that you
| probably can't with this idea.
|
| So in other words, this is a really crappy version of
| something that already exists. I guess there are three
| takeaways to be had:
|
| 1) We still need large scale energy storage and it simply
| cannot just be a pile of batteries. It really needs to be a
| chemical system and it really has to be able to burn.
|
| 2) But that always takes you down one road: Hydrogen or
| something made from hydrogen. That's the only class of
| chemicals that really works and doesn't involve carbon. This
| causes a lot of conflict since it is definitely not many
| people's favored energy storage idea. And since so much FUD
| has been flung around for so long because of that, many
| people have become convinced that this inevitability is
| actually impossible.
|
| 3) So you usually end up with two alternative ideas:
| Something crazy like burning metals. I've heard of burning
| boron too BTW. This particular proposal is a continuation of
| that way of thinking. Probably they are all DOA ideas. And
| the other is something akin to linking all of the grids
| across world together with vast numbers of HVDC lines. But
| this too is crazy, especially once you realize the sheer cost
| and complexity of it all. Not to mention you are still
| wasting oodles of energy since you have minimal energy
| storage.
|
| So eventually we end up in this cycle of one crazy idea being
| proposed after another, and nothing of importance actually
| being achieved.
| pankajdoharey wrote:
| This is another Aluminium Air battery, same concept different
| metal. None of them considers splitting water is energy
| intensive and inefficient. Another hydrogen fool cell category
| fuel imo.
| throwway120385 wrote:
| Who cares if it's energy intensive or inefficient if our
| other option for using the energy is to run it through a big
| resistor or to not produce it in the first place? This is a
| tool for repeatedly storing and releasing excess energy from
| power plants that can't control their output in response to
| grid conditions. Let's supposed for the sake of argument that
| battery banks were prohibitively expensive in some
| applications, and that hydroelectric storage was too damaging
| to the local environment. In those cases, your only option is
| to either dissipate any excess energy or to not produce it in
| the first place.
|
| What this does, then, is provide you an alternative storage
| medium that is relatively inert until you want to use it. And
| it provides you a simple self-sustatining scalable chemical
| reaction that can be started by supplying some initial heat
| and then goes on to produce even more heat steadily and
| continuously until you run out of fuel.
| photochemsyn wrote:
| Seems like a niche technology, useful if you're sitting on tons
| of scrap iron for example. I recall some proposals for using this
| in long-distance cargo shipping instead of very dirty (and
| fossil-sourced) bunker fuel, but even there synthetic diesel or
| methane from atmospheric CO2 + water might be the more versatile
| solution (and the overall mass of the iron required for say, a
| trans-Pacific journey is an issue). See:
|
| https://swzmaritime.nl/news/2020/02/27/why-iron-could-be-a-s...
|
| > "A disadvantage of iron as a fuel for ships is the relatively
| high specific mass of iron powder and the increase in the weight
| of the iron oxide that is produced during combustion. As a
| result, a ship will lie deeper and deeper during the voyage."
|
| They seem to have a prototype in the works c. 2030.
| wolverine876 wrote:
| > It has an energy density of about 11.3 kilowatt-hours per liter
| --better than gasoline.
|
| How about per gram?
| aredox wrote:
| Sometimes volume is more important than mass (e.g. on a ship).
| lloydatkinson wrote:
| So it's gone from burning non-renewable sources like gas and oil
| to burning... iron.
|
| This feels like a poor stop-gap that will turn into a long term
| solution one day instead of focussing on nuclear fusion/fission,
| solar, wind, beaming energy from space, etc.
|
| I had to lookup a German word for this: Weltschmerz.
|
| > Weltschmerz literally means 'world pain' and refers to a sense
| of world-weariness.
| schwabacher wrote:
| Is iron a potential replacement for coal in steel and cement
| production?
| adrianN wrote:
| Making steel from ore using iron seems a bit weird. If you
| already have a method to reduce the oxide, why not use it on
| the ore?
| wolverine876 wrote:
| Steel in principle is iron + carbon.
| droopyEyelids wrote:
| it could be, but like other posters have mentioned, it takes a
| lot of energy to mine and refine the iron so it'd be in a
| usable state.
|
| I think it's easiest to think of iron as another energy storage
| medium that could ease the peaks of renewable energy, by taking
| excess renewable energy to generate the iron, and oxidizing the
| iron for energy generation during peak demand periods with low
| renewable generation
|
| It's like hydrogen in that way.
| usrusr wrote:
| I used to be very excited about the iron cycle when the first
| news about that brewery appeared. But these days I wonder how
| useful it really is, as an energy store? Won't it start oxidating
| at room temperature unless kept in inert atmosphere? And if
| that's a requirement, is it really that much less trouble than
| plain H2 or some gaseous or liquid intermediate?
| thsksbd wrote:
| There's the kinetics of oxygen transport into a big pile of
| iron powder. If that's not good enough, you can always
| transport it in a closed container with a block of dry ice. You
| don't even have to seal it, just change the chemical potential
| of O2 in Fe.
| moffkalast wrote:
| The trouble level for H2 is reasonably high, so it could very
| well be less.
| csours wrote:
| Yes, and gasoline will evaporate, natural gas will disperse,
| etc. It's kept in a container until they burn it.
| usrusr wrote:
| Sure, but liquids and gases are routinely handled in vessels
| with a maintenance interval of "never" on the inside, I'm not
| so sure that could be transferred to a powder. But this might
| be my lack of knowledge of existing processes in "powdery
| industries" speaking, if those are solved problems there I
| would not know.
|
| Your mention of gasoline evaporating made me realize that
| some of the iron oxidating is probably not all that bad, just
| make sure that there's no ventilation continuously swapping
| in fresh air. I guess I'm looking forward to the next iron
| age!
| csours wrote:
| Handling iron particulate is well-established technology:
|
| https://www.youtube.com/watch?v=PZHpeBubb_M
|
| Note that this is about when it goes wrong, but also that
| it is usually due to cost-cutting measures.
| rbanffy wrote:
| If I remember correctly, the process of recycling iron oxide into
| iron involves carbon monoxide and results in carbon dioxide, so,
| I'm not sure this would be as carbon neutral as they claim.
|
| There are other ways of course, but this is only for storage and
| recycling uses a lot of energy.
| jillesvangurp wrote:
| Iron oxide contains no carbon. So if there is any carbon
| monoxide forming that would have to come from somewhere else.
| Like the co2 in the atmosphere.
| ermir wrote:
| Iron is not widely available in nature as a ready-to-use element,
| it must be processed into elemental iron, which takes a lot of
| energy as input. Therefore this can't be really considered as
| fuel, more like energy storage. You still need fossil fuels or
| nuclear power to turn iron ores into iron, then you have iron
| available for the process described in the article.
|
| I'm not criticizing the process, but it's not accurate to call it
| "fuel" like it could be the solution to replacing fossil fuels.
| c0nsumer wrote:
| The article says this. It wraps up with:
|
| "If these problems can be overcome, you could use renewable
| electricity to produce iron, store it as long as necessary,
| transport it there and then burn it for power when needed, says
| Bergthorson. "Places that have excess energy could make iron,
| and others can buy it. This way, you could commodify renewable
| energy so it can be globally distributed without the need for
| transmission lines. Metals can solve a big problem in the
| renewable energy transition: long-duration energy storage.""
| intothemild wrote:
| Sure you could use renewables to make iron. But that thought
| process also extends to other methods too. You could use
| renewables to make other non renewable fuels.
|
| Why not just skip the middleman? Use renewables?
| neolefty wrote:
| They mention that with hydrogen. It's cheaper to _produce_
| hydrogen but much harder to transport it. Fortunately,
| hydrogen can reduce iron oxide, which turns out to be a
| great complement. Their analysis is that the system cost of
| burning iron and renewing it at electrolysis plants is
| lower cost (and safer) than using hydrogen directly.
| kinnth wrote:
| Renewables are exceedingly bad at storing energy for times
| when sun or wind isn't blowing so you always need a mix.
| red-iron-pine wrote:
| That's not a wind or sun problem, that's a battery and
| transmission problem.
| slashdev wrote:
| Because renewables are intermittent and unevenly located.
| This could potentially solve those problems.
|
| There could be a space for it. Or maybe batteries will just
| always be better. Depends on the full costs of each and the
| use case. Burning fuel to make electricity is pretty
| inefficient, but burning fuel for heat compares better.
| TheGeminon wrote:
| I think this is likely more of an energy storage project,
| rather than an energy production one (which seems to be the
| stance the article takes).
|
| At grid-level, battery tech is challenging, requiring
| technologies like pumped storage that require particular
| environments (e.g. damming a river) and can't really be
| transported.
|
| If this works out you could use excess solar during the day
| to deoxidize the rust produced, and then run the iron
| reactor overnight, or on cloudy, windless days.
| dmix wrote:
| How does that battery/production distinction work? How is
| it a battery if it is consuming/burning a fuel? More as a
| stable fallback or something?
| wongarsu wrote:
| Non-rechargeable batteries are also consuming a fuel. The
| products just stay in the same enclosed container. Same
| with rechargable batteries, just that there the process
| is easily reversible.
|
| It is a bit of a fuzzy distinction. Batteries are
| typically simple chemical reactions that cause electrons
| to move around. But viewed from the outside a hydrogen
| fuel cell behaves the same; so why not call this one a
| battery too (especially since the process is reversible).
| samus wrote:
| A useful distinction seems to be that batteries are solid
| state and don't use high process heat, else something
| would be seriously wrong. Of course, the underlying
| reactions are probably very similar if you look at them
| with a chemist's eye.
| balaga01 wrote:
| Well, if you can burn it to produce energy + spent fuel
|
| and then put back energy in the spent fuel to make new
| fuel again
|
| then you have really a battery. That's how li-ion
| batteries work. The issue is the efficiency: how much of
| the energy you used to recharge the "battery" (iron) is
| going to be available when you discharge (burn) it
| dmix wrote:
| Thanks that makes sense
| balaga01 wrote:
| Well, it ties into the storage issue that we see with
| renewable. We still need energy when there is no wind at
| night. Burning iron at night and regenerating during the
| day could be a solution. It needs to prove that it can be
| competitive with the other methods (compressed air, li-ion
| batteries, flow batteries, molten salts, flywheels...).
| lll-o-lll wrote:
| Here's an out of the box thought. Can we wrap the globe
| in undersea cables or does transmission losses kill the
| idea? Reason being that time zones and hemispheres make
| the "renewable is not always on" problem go away. It's
| always on _somewhere_ , so if there was a global grid you
| don't really need storage?
| intothemild wrote:
| Thank you.
| hn_throwaway_99 wrote:
| > It needs to prove that it can be competitive with the
| other methods.
|
| I think the one thing is that iron storage would be a
| potential _long term_ form of storage, while all those
| other methods that you mentioned are really short term,
| designed primarily just to deal with the daily peaks and
| troughs of renewable production, but not as much the
| "it's been completely overcast for 3 weeks" problem. The
| only other form of storage I'm aware of that is also long
| term like that is pumped water storage, and that is
| obviously very geographically limited.
| rsaesha wrote:
| If using Fe why not iron batteries? Keep the redox,
| remove the energy from the system via eletrical current
| instead of low efficiency heat, boiler and steam engine
| combo.
| hn_throwaway_99 wrote:
| Great point. Fe batteries are very new so I'm not aware
| of the cost/benefit or if Fe batteries still slowly
| discharge over time, but yeah in both cases you're just
| oxidizing iron, so why not take the more direct route to
| generate electrical current directly.
| samus wrote:
| There are also applications where the desired output is
| heat, not electricity. In that case, iron fuel would be
| useful.
| kinnth wrote:
| This is actually the same principle as BTC. High volume cheap
| electricity is used to process random numbers and the value
| is stored as BTC allowing it to be freely transferred once
| first mined.
|
| The green economics of this need some serious consideration
| as i'd be really aware if you can reprocess it and get a
| second reaction for less energy than it cost you to turn the
| rust back into free iron metal.
| jshorty wrote:
| Not sure I agree, on one hand you have actual, physical
| potential energy, on the other hand you have numbers on a
| computer that could become worthless depending on
| unpredictable economic factors.
| cr__ wrote:
| > the value is stored as BTC
|
| What value? Where did any value originate in this process?
| a3w wrote:
| The maniacs who claimed that something had a price on a
| market and cost to create claim that this means value was
| created. From an ecological perspective, nonsense.
| Economically, somewhat sound.
|
| Misappropriated rare resources cause destroyed nature for
| the reason that capitalism said it was sound.
|
| Every joule can only be spent once, but and as long as
| there is no moral coercion, there is a profit to be made
| from pillaging it from the supply.
| noodlesUK wrote:
| There's a pretty big difference between BTC and a burnable
| fuel. It is not possible to turn BTC back into electricity
| directly, it is only possible to turn it into electricity
| by first turning it into money, which then buys more
| electricity (from any, renewable or non renewable) power
| source. You can't ship someone a container of memory sticks
| containing BTC and then they get power out of them without
| burning more fuel or building more solar panels/other
| renewables. The much better comparison would be hydrogen,
| which can be produced using readily available water and
| renewable electricity, shipped, then burned. The difference
| is that hydrogen doesn't really produce much in the way of
| by products when burned.
| kumarvvr wrote:
| If a power plant has sufficient store of Iron, with a complete
| cycle, from burning iron to recovering iron, then it is no
| longer a consumable.
|
| I can imagine a solar plant, making iron in the day and burning
| it in the night and essentially act as a base load plant, the
| holy grail of renewable energy.
| proto-n wrote:
| But also don't underestimate how huge it would be if we could
| store energy efficiently as elemental iron. E.g., produce it
| using solar, burn it for grid energy. Of course that depends on
| the efficiency of the whole process.
| upofadown wrote:
| The definition of the word "fuel" does not include the
| requirement that it was originally found laying around in the
| environment.
| DontchaKnowit wrote:
| Yeah but it pretty much requires that producing the fuel
| requires less energy than the fuel provides, otherwise itd be
| like trading a quarter for a dime.
| bilsbie wrote:
| GOOD Point by my wife. Could this be done with aluminum instead
| of iron?
| alex_young wrote:
| If they require Hydrogen to complete the loop, you're going to
| create a lot of CO2 in the process. 4% of H is produced using
| renewables today: https://rmi.org/the-truth-about-hydrogen/
| TSiege wrote:
| Yes. "Green hydrogen" is largely vaporware at this point. The
| majority of hydrogen we produce is from fossil methane
| antisthenes wrote:
| How/why is this better than molten salt energy storage?
| eddyzh wrote:
| You can store the oxidized iron on a heap outside indefinitely.
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