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$100M xPrize for Carbon Removal

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Re: $100M xPrize for Carbon Removal

#301

Post by lucb1e »

Mizza wrote: post #223
lucb1e wrote: post #187

Earlier quoted context omitted.

> carbon sequestration [will] likely require energy Yes, but that doesn't mean we won't need it. Take air planes. We can't just put batteries in there: too low energy density or something (I'm no physicist, but they won't fly very far is what I gather). But by capturing the CO2 (at exhaust, or atmospherically) that they put out, we can have both airplanes and a stable climate -- assuming it's all done right. Who want…

One of the more exciting things in green aviation is "air to fuels". There are companies working on converting atmospheric carbon into hydrocarbons for storage (using renewable energy). Those hydrocarbons can then be used as jet fuel, so it's isn't carbon-negative, but at least it's carbon-neutral. Any hydrocarbons left over that are stored are carbon-negative.

Ack, I know of those. Isn't that the same thing as carbon capture? It also uses more energy to capture the carbon than the fuel will produce after burning. Just that the output is usable fuel (yay put it back in the atmosphere ^^' but better burning circular than burning fossil fuels) rather than rocks like Climeworks and Olivine output.

I never actually saw anyone compare the options. Anyone know if it's cheaper (or less energy-intensive) per ton of CO2 to turn atmospheric CO2 into rock and continue using fossil fuels for another century until oil really starts playing hard to get, or if it's cheaper (or less energy-intensive) to use this air-to-fuel technology?

Re: $100M xPrize for Carbon Removal

#302

Post by lutorm »

lovemenot wrote: post #252
geogra4 wrote: post #203

Earlier quoted context omitted.

I'm laughing but honest to god I think this could work...somehow.

Yes, this seems to have potential. The beauty of proof of work is the hashing algo is both 1) very hard to solve and 2) very easy to verify by anyone anywhere. Furthermore, 3) miners have a financial incentive to solve the algo and 4) They may do so in anyway they see fit. At a minimum a crypto-like solution should have these four properties. Now we already have a lot of unpaid CO2 miners (plants) doing it inefficien…

Why not just turn CO2 into a currency directly then? Your "proof of work" is the CO2 you sequestrated and can sell to someone else.

Re: $100M xPrize for Carbon Removal

#303

Post by lovemenot »

lutorm wrote: post #302
lovemenot wrote: post #252

Earlier quoted context omitted.

Yes, this seems to have potential. The beauty of proof of work is the hashing algo is both 1) very hard to solve and 2) very easy to verify by anyone anywhere. Furthermore, 3) miners have a financial incentive to solve the algo and 4) They may do so in anyway they see fit. At a minimum a crypto-like solution should have these four properties. Now we already have a lot of unpaid CO2 miners (plants) doing it inefficien…

Why not just turn CO2 into a currency directly then? Your "proof of work" is the CO2 you sequestrated and can sell to someone else.

I think it's for the same reasons we tend to abstract currencies away from their underpinning scarce resources. Convenience, scale, efficiency.

Most mining devices don't actually ever successfully win a single bitcoin. But they get paid pro rata for their contribution to the combined hashing power, which did.

For miners in a pool hashing power is the saleable commodity. Perhaps this was the point you were making.

Even if it didn't fulfill its potential (yet), we must remember what made bitcoin so special: eliminating the double-spend and central authority problems. How do you intend to sell your sequestered CO2 and prove that it's still yours to sell?

This is all hypothetical anyway. To my knowledge there's no scheme that satisfies those criteria wrt proof of sequestration.

Re: $100M xPrize for Carbon Removal

#304

Post by schiffern »

fooker wrote: post #224
mbgerring wrote: post #148

Earlier quoted context omitted.

There's no reason not to plant trees in addition to everything else we'll need to do to fix this problem. The advantage of planting trees is that we know it works, it's cheap, and we can do it right now. So some people should be doing that, and others should be doing R&D on other means of carbon removal. No need to pit one against the other.

>There's no reason not to plant trees in addition to everything else we'll need to do to fix this problem. Yes, there is. Trees take a up valuable real estate. As long as people can do something even remotely profitable with land they own, this can not work.

Trees are valuable too. The problem is we don't understand and/or appreciate that value.

For instance, trees essentially power the entire terrestrial water cycle. Without trees all the water rains out within a few hundred km of the coast. Trees (far moreso than simple evaporation) are responsible for pushing that water back into the air-stream. Isotopic analysis confirms that 80% of the rainfall on land is caused by transpiration, and most of that is trees. https://www.nature.com/articles/nature11983

This explains why deforestation causes desertification. Cut down the trees and you get a continent-wide desert.

These dynamics aren't well-captured by the present economic system, which only sees "valuable real estate" being "taken up" by trees.

Re: $100M xPrize for Carbon Removal

#305

Post by wyager »

PeterisP wrote: post #271
wyager wrote: post #83

Earlier quoted context omitted.

If you can increase arable land then other trees will grow there. I would prefer to create as much biomass as possible. Surely the net biomass stored in fossil fuels could be completely resuscitated, so to speak.

The usual way to increase arable land is by cutting down a forest. "Surely the net biomass stored in fossil fuels could be completely resuscitated, so to speak." - that's a strong no - fossil fuels have accumulated over millions of years, having all that carbon become biomass all at once would not be returning to something that existed earlier but something completely unprecedented, it would require many times more b…

A quick google search suggests there are about 500 trillion pounds of oil left and about 1000 trillion pounds of living biomass. Assuming 5:1 mass:carbon ratio, it shouldn’t more than ~quadruple the total biomass. We could definitely fit that by turning the Sahara into a rainforest or something.

Re: $100M xPrize for Carbon Removal

#306

Post by wanderingmind »

detritus wrote: post #274
Mizza wrote: post #264

Earlier quoted context omitted.

Have you done the math on that? It seems like it would take an awful lot of poop to counteract a coal fired power plant.

A city such as London (where I'm at) generates about 3600 tonnes of wet mass poop a day. Thanks for making me work that out... . Given poop isn't even a main constituent ingredient in new soil, but rather forms the 'flavouring' for the development of the biological and mineral matter otherwise, I'd suggest a well-developed bio-recycling infrastructure could be quite productive. This isn't even factoring in food or fa…

But how do you move the wet waste from London to Mediterranean and Sahara. Also soil is one part of equation. Water is another. Poor soil results in poor vegetation that leads to poor rainfall and water sources. So soil also needs to be coupled with water increase. I think preservation is probably more feasible than rejuvenation. India for example is losing top soil at unprecedented rates that can have devastating consequences.

Re: $100M xPrize for Carbon Removal

#309

Post by gpt5 »

malloryerik wrote: post #286
gpt5 wrote: post #268

Earlier quoted context omitted.

Genuine question - if CO2 half life in the atmosphere is less than 50 years, why are we so concerned about it? Wouldn’t the problem solve itself given that we are both reaching peak consumption of fossil fuels and that they are expected to deplete with the next century? In other words, wouldn’t the co2 concentration go down naturally within the next 100 years even if we let thing run naturally?

It looks as though those numbers are mistaken. https://blogs.edf.org/climate411/2008/02/26/ghg_lifetimes/

This article seems to conflate "Time it takes for 50% of the CO2 increase to be removed from the atmosphere" with "time it takes a specific molecule that was released to the atmosphere to be removed".

The former is more relevant to the discussion, and is stated as ~30 years.

Re: $100M xPrize for Carbon Removal

#310

Post by pjerem »

gpt5 wrote: post #268
daddylonglegs wrote: post #236

Most types of carbon capture technology [1] being touted are credit cards for climate change: You burn enough fuel to generate 4MJ worth of heat... Your internal combustion engine generates 1MJ worth of mechanical effort from this... You use this to propel a 2 ton vehicle... Carrying 1 person... To take part in the rat race or indulge in some consumerism. [2] The carbon dioxide sits in the atmosphere for 50 years whe…

Genuine question - if CO2 half life in the atmosphere is less than 50 years, why are we so concerned about it? Wouldn’t the problem solve itself given that we are both reaching peak consumption of fossil fuels and that they are expected to deplete with the next century? In other words, wouldn’t the co2 concentration go down naturally within the next 100 years even if we let thing run naturally?

Because if it’s somewhat true to say that stopping CO2 emissions would rapidly pause climate change, there is no short term « reverse » (in hundreds of years) of the climate.

We are in such a situation that every +0.01°C increase in global warming is gained more or less indefinitely.

The only thing we can do is stopping net emissions and learn to live with the climate as it is when we achieve this.

We really don’t care a lot about concentrations going down in the next centuries because by the time it happens, the harm would be done already for multiple centuries.

We are really facing today, 50°C in summer and devastating events, for our generation and our kids. This precise battle is already lost but we must fight for it to not be even more dramatic.

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