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Solving climate change by abusing thermodynamic scaling laws

ckrapu.github.io

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Re: Solving climate change by abusing thermodynamic scaling laws

#31

Post by lupire »

onethought wrote: post #26
bryanrasmussen wrote: post #23

Earlier quoted context omitted.

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.

Isn’t this why solar is good. We already have the heat sink (earth) we just aren’t using the energy.

Not exactly because the Earth naturally reflects a large amount of solar energy back into space.

Re: Solving climate change by abusing thermodynamic scaling laws

#32

Post by FooBarBizBazz »

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?

Re: Solving climate change by abusing thermodynamic scaling laws

#33

Post by pstrateman »

FooBarBizBazz wrote: post #32

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…

Simple math unfortunately.

To offset global human CO2 production you'd need to biochar all plant matter several times a year.

Re: Solving climate change by abusing thermodynamic scaling laws

#34

Post by gmuslera »

xbmcuser wrote: post #19

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 ener…

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.

Re: Solving climate change by abusing thermodynamic scaling laws

#35

Post by FooBarBizBazz »

pstrateman wrote: post #33
FooBarBizBazz wrote: post #32

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…

Simple math unfortunately. To offset global human CO2 production you'd need to biochar all plant matter several times a year.

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.

Re: Solving climate change by abusing thermodynamic scaling laws

#36

Post by schiffern »

philipkglass wrote: post #7

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 ero…

  > 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.

Re: Solving climate change by abusing thermodynamic scaling laws

#37

Post by ckrapu »

pxeger1 wrote: post #2

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?

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.

Re: Solving climate change by abusing thermodynamic scaling laws

#38

Post by ckrapu »

hnmullany wrote: post #17

Methane and nitrous oxide emissions from these piles would likely be rather high, potentially negating any carbon sequestration benefits

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?

Re: Solving climate change by abusing thermodynamic scaling laws

#39

Post by ckrapu »

wolfram74 wrote: post #10

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?

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.
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