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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

#141

Post by nomadluap »

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?

You can pyrolize the wood by cooking it in an oxygen-free environment, cooking off almost all of the nitrogen and other nutrients and leaving nearly pure carbon in the form of charcoal.

Off the top of my head, for a given amount of wood biomass, you can get about a 70% ratio of product to fuel if you use a high-efficiency wood fire to cook the wood itself.

Then you can take that carbon, bury it in decommissioned open pit mines, or use it as a soil additive (biochar), where it will sequester the carbon for thousands of years and act as a fertilizer.

You could also pair the biochar with a fast-growing swamp tree (willow?), re-incorporating the char into the areas around the willow plantation to create a sort of artificial peat bog which could also be useful for water storage and filtration.

Re: Solving climate change by abusing thermodynamic scaling laws

#142

Post by AnthonyMouse »

codethief wrote: post #112
AnthonyMouse wrote: post #74

Earlier quoted context omitted.

The point is that you can have exponential growth in human energy consumption without exponentially heating the Earth by having the growth take place off-planet. Which is hardly irrelevant to the people still there, e.g. if you find your data centers are using too much power, put them in space. The computation may take a megawatt-hour but transmitting the result back to the surface is only a few watt-seconds for a ra…

> e.g. if you find your data centers are using too much power, put them in space. …put them in space how far away from Earth exactly? If they're too close, the heat they radiate away will end up on Earth again. If they're too far away, latency & maintenance will become an issue.

> If they're too close, the heat they radiate away will end up on Earth again.

So put a mirror on the Earth side of it?

> If they're too far away, latency & maintenance will become an issue.

There are many compute tasks where latency is irrelevant. To take a recent example, AI model training. It does not matter if the compute farm is a few light minutes away when the computation itself is going to take days to months.

Maintenance is performed locally. It's not as if you're going to have Earth and then a single solitary server farm on the far side of the Sun. By the time this becomes relevant to planetary energy there are multiple space stations with permanent staff.

Re: Solving climate change by abusing thermodynamic scaling laws

#143

Post by AnthonyMouse »

carapace wrote: post #139
AnthonyMouse wrote: post #102

Earlier quoted context omitted.

> It doesn't matter, unless you postulate that the people left behind have zero population growth and constant energy dissipation, which seems unrealistic? Why does it seem unrealistic? More than that, you only need one of those things. You could have population growth with declining energy consumption if energy use is moved off-planet (even if the population benefits from the off-planet use), or increasing local ene…

At this point we're just trading sci-fi story ideas. If we can learn to manage our population growth and/or energy consumption growth, then that's awesome! Watch the Bartlett lecture.

The original claim was essentially that energy use can't increase past a certain point because it would result in too much energy density. The obvious flaw in the claim is that it assumes no ability to increase the volume of space in which the energy use takes place, which is an invalid premise. Space is really big.

Re: Solving climate change by abusing thermodynamic scaling laws

#144

Post by adrianN »

Self-Perfection wrote: post #140
Y-bar wrote: post #122

Earlier quoted context omitted.

You're not wrong. That said I want to take issue with one thing: Between the lines there is a suggestion that doing a small positive action is useless. But that implies that there is either a silver bullet-type solution where doing only one major thing will resolve the problem of climate change, or that there is no possible way we can resolve it. I want to counter the implication by saying that the problem of solving…

The only thing we need to implement from your list is the carbon tax. But it has to be sufficiently high. The rest will happen without extra nudging just because doing it "the wrong way" will be too expensive. By feeding carbon tax money into carbon extraction we can eventually start reducing amount of carbon in atmosphere.

It’s probably too late for a tax-only solution. Either the tax is too low to have the necessary effect, or people will overthrow the government who instated it. The change we need has become quite drastic.

Re: Solving climate change by abusing thermodynamic scaling laws

#145

Post by philipkglass »

bbor wrote: post #92
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…

Hmm. Assuming I’m on board with apocalypse, this kinda seems like a hat on a hat. Couldn’t we destroy the magnetosphere and vent the atmosphere with less energy than it would take to get all that carbon out? Or, hell, deorbit the moon one more time? I guess it’s harder to ramp up that tech in secret/with a benign excuse. Plus a lot of it’s in living beings — you’d either have to find and harvest/burn all of them manu…

Couldn’t we destroy the magnetosphere and vent the atmosphere with less energy than it would take to get all that carbon out? Or, hell, deorbit the moon one more time?

I think that both of these require far more energy than keeping carbon locked out of terrestrial circulation (and hence out of living things). Don't you have to destroy the Earth's iron core to destroy the magnetosphere? You barely have to scratch the Earth's crust in my scheme. Of course my scheme requires much more time to work, so it's not very flashy.

This idea came to me while considering that most science fictional planet-sterilizing weapons use imaginary physics (The Three Body Problem, Revelation Space, the Xeelee Sequence, The Forge of God...) or, at the very least, a stellar-scale expenditure of energy (The Killing Star). What's the most energy-efficient approach that is compatible with known physics?

Total carbon sequestration doesn't work against a prepared adversary with near-peer technology, but it works great as an alien device for quietly exterminating life from selected planets. The thing is like an invasive species made of silicon that no carbon-based life can compete or coexist with.

Re: Solving climate change by abusing thermodynamic scaling laws

#146

Post by ckrapu »

jacknews wrote: post #131
ckrapu wrote: post #45

Earlier quoted context omitted.

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.

Indeed if you insulate the pile as the OP suggests, the entire pile should reach pyrolisis temperatures.

That does seem like a much better approach than freezing it, then.

Re: Solving climate change by abusing thermodynamic scaling laws

#147

Post by avidiax »

Y-bar wrote: post #122
avidiax wrote: post #93

Oil formed over millions of years at a rate of about 80,000 barrels / year. We consume 36.4 billion barrels of oil per year. That means we consume oil about 455,000 times faster than it was originally produced. And this is just oil; I'm not counting coal and natural gas. Trying to reverse that process by taking a fraction of one year's plant growth and sequestering it is probably 5-6 orders of magnitude too little to…

You're not wrong. That said I want to take issue with one thing: Between the lines there is a suggestion that doing a small positive action is useless. But that implies that there is either a silver bullet-type solution where doing only one major thing will resolve the problem of climate change, or that there is no possible way we can resolve it. I want to counter the implication by saying that the problem of solving…

I agree that implementing 10 ideas that tackle 5% of the problem is valuable. Maybe 100 ideas that tackle 0.5% of the problem each.

But ideas that tackle 0.00001% of the problem are more useful as a counterexample of what doesn't work.

I haven't looked into large scale technical solutions to climate change, but they seem quite unlikely to scale in relation to the consumption of fossil fuels.

Sure, coal-burning plants could add carbon capture at the source. But as we decarbonize, we will be left with the use cases like aviation and off-grid mobility where carbon capture at source isn't feasible technically or economically.

The only thing that will really work (has the right magnitude of effect) is to stop digging carbon out of the ground and burning it without capturing the carbon at the source, or block the sun's rays so that more energy is reflected to space.

Re: Solving climate change by abusing thermodynamic scaling laws

#148

Post by realusername »

naasking wrote: post #134
realusername wrote: post #114

Earlier quoted context omitted.

What does thermodynamically unviable means? There's no thermodynamic laws specifically on carbon.

I haven't crunched the numbers on this, but CO2 air capture is incredibly inefficient, and it consumes energy which itself releases heat. So if the amount of CO2 you capture reduces heat by X degrees but you release Y degrees in energy consumption to achieve that where Y > X, that would be one interpretation of "thermodynamically unviable". It seems implausible to me but not impossible.

The effect of the heat released in the air is negligible compared to the greenhouse effect.

CO2 capture might be economically unviable but nothing physically prevents it from working.

Re: Solving climate change by abusing thermodynamic scaling laws

#149

Post by gmuslera »

xbmcuser wrote: post #106
gmuslera wrote: post #34

Earlier quoted context omitted.

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…

The past decade does not matter as till this year consumption growth was more than renewables additions that has changed in 2023 and will accelerate from 2024. So the tipping point has just been reached add electrification of transport and heating and fossil fuel use will come down a lot faster than people owning fossil fuel reserves would like for the world to realize. In 2024 we will add almost more solar than all…

The problem is not how much solar we add, but that it is not corresponded with a reduction of demand of fossil fuels. Not sure about 2024, but at least for the years of the ourworldindata info it was still on its way up. And the solution is not just maintaining the same levels of the previous year, but dropping to zero far before there is no way out anymore.

Re: Solving climate change by abusing thermodynamic scaling laws

#150

Post by carapace »

AnthonyMouse wrote: post #143
carapace wrote: post #139

Earlier quoted context omitted.

At this point we're just trading sci-fi story ideas. If we can learn to manage our population growth and/or energy consumption growth, then that's awesome! Watch the Bartlett lecture.

The original claim was essentially that energy use can't increase past a certain point because it would result in too much energy density. The obvious flaw in the claim is that it assumes no ability to increase the volume of space in which the energy use takes place, which is an invalid premise. Space is really big.

No, dude, even if you postulate FTL spaceships, the size of the Universe doesn't matter, you always eventually become an explosion. All exponential growth curves are S-shaped.

At this point I'm just repeating basic physics and math at you. I think we both have better things to do with our time. Have a good day.

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