[HN Gopher] Solving climate change by abusing thermodynamic scal...
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Solving climate change by abusing thermodynamic scaling laws
Author : ckrapu
Score : 55 points
Date : 2024-09-29 06:17 UTC (16 hours ago)
(HTM) web link (ckrapu.github.io)
(TXT) w3m dump (ckrapu.github.io)
| pxeger1 wrote:
| What are you gonna do about all the nitrogen etc which the plants
| need? Are there good ways to reextract these nutrients from dead
| plant material without releasing loads of carbon at the same
| time?
| fgeiger wrote:
| I wonder the same. This proposal sounds like it is leeching
| nutrients from the ground and storing it for a long time (on a
| scale of centuries in the proposal). How do these nutrients
| cycle back for growing the food that we need? Or, for that
| matter, for the next round of biomass to freeze?
| ckrapu wrote:
| Sadly, I don't think so. Many of these carbon
| burial/sequestration proposals all advocate just taking all of
| the plant matter and tucking it away, including the N and P.
| prawel wrote:
| much better option than stratospheric aerosol injection, it's
| easily reversible
| 8474_s wrote:
| wouldn't it be much simpler to just mass produce more furniture
| out of wood, instead of keeping the same-equivalent biomass
| frozen infinitely?
| philipkglass wrote:
| There's not enough useful demand to tame CO2 this way.
|
| Anthropogenic emissions of CO2 are currently about 37 billion
| tons per year:
|
| https://ourworldindata.org/co2-emissions
|
| That's enough CO2 to make 22.7 billion metric tons of cellulose
| per year, or ~2.8 tons per capita for Earth's 8.2 billion
| people. That's too much to to turn it all into furniture or
| even buildings.
| scotty79 wrote:
| Maybe horizontal surfaces too? Like roads and pavements?
| Let's become industrial elves.
| euroderf wrote:
| Didn't there used to be a "Pave the Earth" meme ? Maybe
| update it for log roads.
| edhelas wrote:
| 2/3 of the CO2 stored in forest is in the ground, not the
| trees, it's accumulated when the forest grows and is getting
| generations of trees.
|
| Cut those trees to do furniture and you'll release all this
| CO2, do a culture of tree decades after decades and you'll
| never store it back.
| laserbeam wrote:
| I'd wager the furniture industry is currently responsible for a
| significant % of anual deforestation, which as far as I know
| isn't regrowing fast enough.
|
| An approach like this could benefit from crops which are not
| productive for humanity otherwise, but which grows much faster
| and eats CO2 cheaper than trees.
|
| Does that mean "stop replanting forests?" Absolutely not.
| jacknews wrote:
| Or just burn the huge piles to charcoal (pyrolysis), then you're
| only storing carbon, and it certainly won't decay. Even use it as
| a soil enhancer.
| ckrapu wrote:
| Let's say that we have a hollowed-out zone in the middle of the
| biomass pile where we tolerate limited oxidization so we can
| run a fire. If the rest of it is wet, maybe the heat from that
| combustion could pyrolyze a large radius of surrounding
| material since O2 flow into the system should be small.
| philipkglass wrote:
| I'm going to share my own insane idea for drawing down
| atmospheric CO2.
|
| Capture CO2 as biomass or with direct air capture. Pyrolyze
| biomass to charcoal or use the Bosch reaction to recover pure
| carbon from CO2 chemically [1]. Then _combine the carbon with
| silicon_ to form silicon carbide via the Acheson process:
|
| https://en.wikipedia.org/wiki/Acheson_process
|
| Silicon carbide is extraordinarily resistant to mechanical
| erosion, oxidation, or any kind of natural degradation. Put the
| silicon carbide in a geologically stable desert and it could keep
| the carbon out of the carbon cycle until the sun grows hot enough
| to render the Earth uninhabitable. Continually extract and
| convert CO2 from the atmosphere and oceans until natural CO2
| levels drop near zero and the desert is full of silicon carbide
| mountain ranges.
|
| As a mere mitigation for AGW, this is a stinker. It requires an
| order of magnitude more energy and complexity than direct air
| capture of CO2 (which itself is already too energetically
| demanding and complex). But if you have the Sahara-sized robotic
| solar farm and industrial complex to put it into practice, it
| makes a _great_ doomsday weapon!
|
| Most actually-buildable doomsday weapons leave numerous survivors
| behind. Ordinary global nuclear war would barely deplete
| uncontacted tribes in the Amazon. Cockroaches would still survive
| cobalt salted nuclear warfare at the gigaton scale. Even an army
| of roving Terminators might eliminate multicellular life yet
| struggle to locate protozoans.
|
| But I think that Total Carbon Sequestration could end _all_ life,
| not just the visible-to-the-naked-eye species. All life needs
| carbon. And no species (save humans, via technological means) is
| capable of extracting carbon from silicon carbide. So with a
| hundred trillion dollar investment in a fully autonomous complex
| of solar farms, carbon capture facilities, and silicon carbide
| factories, I believe that we could solve global warming _and_ end
| all life on Earth. Just like the Earth will do naturally in about
| a billion years [2] as CO2 levels fall, but up to 10,000 times
| faster! I 'm still working on a funding model and a rationale for
| why this should be done at all, but some things are inspiring
| just because they're possible.
|
| [1] https://en.wikipedia.org/wiki/Bosch_reaction
|
| [2] https://en.wikipedia.org/wiki/Timeline_of_the_far_future
| AstralStorm wrote:
| Direct CO2 capture is thermodynamically unviable, and literally
| every plan and attempt involving it was highly expensive in
| energy.
| Retric wrote:
| Not all life is connected to earths atmosphere. That that
| doomsday weapon is missing caves which contain multicellular
| life across geologic timescales. The ecosystems dependent on
| chemical synthesis at deep ocean vents would similarly be
| unaffected.
|
| You might kill off plants though frozen seeds are viable for an
| extended period, but the incoming ice age is going to preserve
| aglee until atmospheric CO2 returns to normal even if we're
| talking millions of years.
| philipkglass wrote:
| The incoming ice age could be averted by simultaneously
| adding carbon-free greenhouse gases like nitrous oxide to the
| atmosphere, but I suppose that kills the "solving global
| warming" part of the pitch.
|
| _Not all life is connected to earths atmosphere. That
| doomsday weapon is missing caves which contain multicellular
| life across geologic timescales. The ecosystems dependent on
| chemical synthesis at deep ocean vents would similarly be
| unaffected._
|
| That's a good point and I don't see a way around it.
| ckrapu wrote:
| A flawed doomsday weapon but a good mechanism for building
| a fictional world where the biosphere develops underground.
| schiffern wrote:
| > All life needs carbon. And no species (save humans, via
| technological means) is capable of extracting carbon from
| silicon carbide.
|
| A "species" doesn't need to do it, simple rock cycling will do
| the job.
| specialist wrote:
| Love it. I'm firmly in the Yes And camp.
|
| Could you also produce for the sizeable and growing SiC market?
| It'd be cool if your source was competitive (assuming green H2
| level subsidies).
|
| --
|
| As you know, once we achieve net-zero (2050), we'll have to
| accellerate into net-negative. From the hip, maintaining
| current growth of renewables (17% YoY), we'll cover expected
| demand 2045-2050. Then what?
|
| Methinks each and every carbon sequestion idea and strategy
| should be attempted. Like starting with obscene funding amounts
| for yearly DARPA style x-prizes. Winners advance to the next
| round.
|
| And hopefully some of the strategies are scaling in time to
| soak up the excess production.
| gus_massa wrote:
| > _But if you have the Sahara-sized robotic solar farm and
| industrial complex to put it into practice, it makes a great
| doomsday weapon!_
|
| 1) Can the other side just nuke most of it?
|
| 2) Isn't it cheaper to build a few thousand nukes instead of a
| Sahara-sized solar farm?
| ospray wrote:
| The globe is mostly water. Ocean fertilization make a lot more
| sense than this for a whole bunch of reasons. The inter-
| continental sea floor automatically freezes all carbon that goes
| down there most of it is stored as methane. Just need a fleet of
| nuclear powered fertilizer ships to kick it off hopefully you get
| more fish as a result.
| https://en.m.wikipedia.org/wiki/Ocean_fertilization
| AstralStorm wrote:
| Unfortunately the plan is very dangerous as tectonic activity
| has a tendency to release it plus any hurricane or monsoon or
| thaiphoon or such has a tendency to destroy the installation or
| worse, move it somewhere where it will do damage to the
| ecosystem.
|
| Also, use solar and wind ships instead. We don't need to sink
| more nuclear material...
| cynusx wrote:
| No need for fertilizer ships.
|
| The delivery of material to the center of Ocean vertices is
| essentially free. Any floating body winds up there eventually
|
| I wrote about it here: https://noverloop.substack.com/p/how-to-
| leverage-the-plastic...
| ckrapu wrote:
| One downside: you have to ship all the carbon to the coast.
| Transport is a non-negligible consideration for all of this.
| Ideally, you just grow a ton of switchgrass in northern US /
| Canada / Siberia and store it nearby.
| wolfram74 wrote:
| A structural question comes to mind, if the pipes are arrayed
| horizontally, how important is it to keep the pipes straight
| while they're being compressed by metric tons of biomass? Are
| they at risk of being squished closed? It's too late at night for
| me to ball park the pressures involved, but it'll be something
| like an extra atmosphere of pressure every 20 to 30 meters? This
| thing is over a hundred meters tall?
| ckrapu wrote:
| Great point. I handwave this away by saying that most of the
| biomass will be frozen most of the time, providing the
| necessary structural support.
| laserbeam wrote:
| I'm skimming through this and it feels like a well thought out
| research proposal with concrete next steps. My thermodynamics is
| too bad to comment on the approach but it looks cool. As long as
| setting up experiments for it is reasonable in cost, wouldn't
| take too long to show results (before it's too late for the
| planet), and can show that enough CO2 can be captured and long
| term costs make sense, then it sounds great! I hope some of the
| proposed next steps get funding.
|
| Commenting "wouldn't Z be better instead" feels counterproductive
| to the discussion here.
| hnmullany wrote:
| Methane and nitrous oxide emissions from these piles would likely
| be rather high, potentially negating any carbon sequestration
| benefits
| aqme28 wrote:
| Methane would be extremeley high. The core of the pile might be
| frozen, but the unfrozen region would be anoxic and
| decomposing.
| ckrapu wrote:
| This is definitely true.
|
| My hope would be that the thawed region would be a very thin
| shell overall, so the overall emissions as a fraction of total
| stored mass would be relatively low. Can you think of any ways
| to minimize anoxic activity in the thermally active area?
| xbmcuser wrote:
| This year ie 2024 world will add more solar power than the total
| consumption growth. This is despite the tariffs and sanctions on
| Chinese panels and batteries. I think the world is at the cusp of
| dramatic change that would come faster if not for western
| countries trying to protect their industries. I think adding more
| renewables as fast as possible specially solar is the best option
| as this will make essentially energy free which will decrease
| carbon production as well as allow to use the energy to capture
| carbon. Maybe we can get some nuclear fission or fusion
| breakthrough in the future but adding solar, wind and batteries
| as fast as possible should be the main focus for now.
| bryanrasmussen wrote:
| there was a quote, and I can't remember exactly so I
| paraphrase: "the person who creates a new form of energy for
| the world, without creating an equivalent heatsink, would be
| history's greatest monster", although I suppose that is very
| perfect being the enemy of the good.
| codethief wrote:
| I don't think that is "very perfect being the enemy of the
| good" at all. Any new energy source (like fusion) would be a
| very real threat to mankind, see also
| https://dothemath.ucsd.edu/2012/04/economist-meets-
| physicist...
| hcurtiss wrote:
| He very early assumes/disregards we remain confined to
| earth. In the face of exponentially growing energy
| resources, this is a terrible assumption.
| onethought wrote:
| Isn't this why solar is good. We already have the heat sink
| (earth) we just aren't using the energy.
| lupire wrote:
| Not exactly because the Earth naturally reflects a large
| amount of solar energy back into space.
| gmuslera wrote:
| So far we are still increasing the rate at which we extract
| fossil fuels, even with all the investment in renewables and
| alternate power sources in the last decades
| (https://ourworldindata.org/fossil-fuels). The Jevon paradox
| seem to still be valid in this, even with a few countries that
| managed to have most of their energy matrix on clean sources.
|
| And with all the time that CO2 remains in the atmosphere it is
| not enough to just extract a bit less, thing that still may
| take years to be achieved, all that was managed to be captured
| by some expensive carbon capture technology is probably orders
| below of how much we increased emissions. Absolute global
| numbers matters here.
|
| And yes, it is not possible to just stop extracting fossil
| fuels and try to solve our energy needs with what we have built
| so far. But time is running out (if it is not over already).
| Severe drop in consumption should be in the map too, there was
| a shortlived dent in the trends around 2020.
| seu wrote:
| Nice idea, but the climate crisis is not solved with technology
| (we already know and have everything we need) but by politics and
| changing our consumption habits.
| criddell wrote:
| People don't want to change consumption habits and they aren't
| going to vote for politicians who want to change consumption
| habits, so technology is the only hope.
| RhysU wrote:
| Are the going prices for carbon credits sufficiently high that
| this approach could be commercialized?
| aqme28 wrote:
| Is there some plugin I'm missing for the LaTeX to render, or did
| they miss a step when publishing?
| ckrapu wrote:
| I had an issue with an out-of-date mathjax configuration,
| sorry! I've updated it.
|
| Is it still not rendering? It looks fine in my browser.
| FooBarBizBazz wrote:
| Why doesn't the obvious thing, i.e., making charcoal, work? You
| can call it "biochar" if you want. A big pile runs the risk of
| catching fire, but if it's mixed with soil I'd think it won't
| burn. Is there some slow oxidation process to worry about? I'd
| think that charcoal briquettes, pencil leads, and soot would all
| last essentially forever.
|
| Plus, you can harness the pretty-high-grade heat energy extracted
| during the charcoal-making, to run heat engines or for other
| uses. So it's basically a way to use biology to get some solar
| power, and to sequester carbon at the same time.
|
| If you're talking about only the charcoal-making, then this is
| prehistoric technology, and if you throw heat engines into the
| mix then you're at maybe an 1880s tech level. Seems easy?
|
| I guess the "giant pile of frozen vegetables" method is even
| simpler in some ways (pipes being the only tech), but it also
| seems less stable, and it doesn't return the non-carbon nutrients
| to the soil.
|
| What am I missing?
| pstrateman wrote:
| Simple math unfortunately.
|
| To offset global human CO2 production you'd need to biochar all
| plant matter several times a year.
| FooBarBizBazz wrote:
| This feels like a "yes, and" thing, where the most important
| use of effort is to reduce production (and we're nowhere
| close yet), but at some point we'll need to also do capture
| to deal with production that is truly unavoidable, and, if
| we're dreaming, to achieve net negative production, for the
| purpose of returning to preindustrial levels.
|
| But yeah, if you're burning coal with one hand and making
| charcoal with the other, it's all pretty pointless.
| pstrateman wrote:
| Reducing production is simply impossible.
|
| There's billions of people on earth who are desperately
| poor compared to even the poorest American.
|
| There is absolutely no chance those people just accept
| their position as ultra poor.
|
| If individuals want to reduce their CO2 output the only
| viable strategy is to buy and permanently store fossil
| fuels.
| schiffern wrote:
| >we avoid most capital expenditures... since no provision must be
| made for moisture management or geotechnical engineering
|
| No summer rains in this (presumably agricultural) project area?
|
| I see no math for heat transfer due to rainwater percolation
| through the pile. "Assuming all voids are filled with water" is
| great and all, but (with apologies to _Jurassic Park_ ) water...
| uh... finds a way. Meltwater will even tunnel its way through
| compacted glacial ice.
|
| Plus the "dry" insulation layer won't stay dry for long.
| ckrapu wrote:
| Good catch :)
|
| I thought about this for awhile and the gap between harvest
| time for many crops and first frost isn't enough to get more
| than a few inches of rainfall in most agricultural regions with
| favorable economics.
|
| I think the wetness will wreck the insulation of the first
| meter or so, but won't lead to much convective heat transfer if
| the outside never gets saturated. A big if, to be sure.
|
| As an aside, it's common practice to leave large piles of grain
| outside overwinter in the central USA and it's not optimal, but
| they certainly don't saturate the whole way through with water.
| schiffern wrote:
| Beyond that gap time period, I was thinking more about
| longer-term storage and heat transfer. What happens over the
| second summer?
|
| Grain piles have free drainage so we don't expect saturation,
| but if water freely drains through this system it seems
| problematic.
| microbug wrote:
| no one understands uncertainty
| carapace wrote:
| I'm reminded of Pykrete:
|
| > Pykrete is a frozen ice composite, originally made of
| approximately 14% sawdust or some other form of wood pulp (such
| as paper) and 86% ice by weight (6 to 1 by weight).
|
| > Pykrete features unusual properties, including a relatively
| slow melting rate due to its low thermal conductivity, as well as
| a vastly improved strength and toughness compared to ordinary
| ice. These physical properties can make the material comparable
| to concrete, as long as the material is kept frozen.
|
| > Since World War II, pykrete has remained a scientific
| curiosity, unexploited by research or construction of any
| significance.
|
| https://en.wikipedia.org/wiki/Pykrete
| semiinfinitely wrote:
| nice glad its solved now. great headline
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