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$100M xPrize for Carbon Removal

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Re: $100M xPrize for Carbon Removal

#81

Post by jeffbee »

quaintdev wrote: post #27
Tuna-Fish wrote: post #24

Earlier quoted context omitted.

At least for terrestrial plants, the math just doesn't work out. Plants are really not fast or efficient enough to suck up carbon in meaningful quantities. Algae can be >100 times as efficient at that than terrestrial plants, so there might be a there there, but even still, fracking basalt probably beats that by a couple of orders of magnitude.

I understand this concern but I was blown away when I heard this fact which I wanted to share with you. > Certain species of bamboo can grow 910 mm (36 in) within a 24-hour period, at a rate of almost 40 mm (11⁄2 in) an hour (a growth around 1 mm every 90 seconds, or 1 inch {2.54 centimeters} every 40 minutes). At least it's better than no trees at all.

Bamboo is something like 5 meters per kilo. You don't really care about the length. You care about the mass.

Re: $100M xPrize for Carbon Removal

#82

Post by filleokus »

typeformer wrote: post #58
filleokus wrote: post #45

I wonder how YC backed Prometheus Fuels will stack up. They claimed that they are able to sequester Co2 directly from the air for around 36 USD / ton [0]. If they truly can scale it at that price point, it seems very competitive. [0]: https://www.prometheusfuels.com/on-the-road/happy-earth-day-...

Are they really sequestering it? If I understand their tech correctly they are recycling it back into fuel which then gets burned and the CO2 goes back into the air? It’s a fascinating process but unlikely to undue our decades of harm.

Yeah, that's how I understand it also. But they are talking about putting it in (plastic) goods "that store it forever". So I'm thinking that they could just solidify it somehow and bury it in the ground? Feels fairly cheap?

But I'm not clear on wether their price point includes the revenue they get from selling the carbon (in the form of fuels or plastic)?

I.e, does it cost them 36 USD, or 351 USD? [0]

[0]: 36 USD + (1 tonne of Co2 / 19 lbs of Co2 per gallon of fuel) * 3 USD / gallon of fuel ≈ 36 + 105*3 = 351 USD. Makes a huge difference...

Re: $100M xPrize for Carbon Removal

#83

Post by wyager »

sevenf0ur wrote: post #33
danuker wrote: post #21

Earlier quoted context omitted.

Planting trees it is very difficult to keep up with global production. TL; DW: planting 20 million trees would equal roughly the CO2 emissions of the USA for half a day. https://www.youtube.com/watch?v=gqht2bIQXIY

Just one of the many problems of fundraisers like Team Trees: 1. Trees will eventually die and release their CO2 through rot or burning 2. Consequences of changing the ecosystem so rapidly

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.

Re: $100M xPrize for Carbon Removal

#84

Post by mvanaltvorst »

mustafa_pasi wrote: post #39
wedn3sday wrote: post #4

Here's my proposal, take that $100M and find a Saudi/Venezuela oil well operator. Give him the $100M in exchange for not pumping $100M worth of oil out of the ground.

That's basically carbon cap and trade. One of the problems is how do you ensure that the oil well remains blocked off forever? The risk of fraud is pretty high, especially when you consider that the involved parties are these huge practically untouchable corporations.

If you have $100M worth of carbon captured from the air stored somewhere under the ground, how do you make sure nobody takes advantage of this vast supply of energy?

You will have to deal with this problem either way, going straight to the Saudi Arabian oil operator just skips the middleman.

Re: $100M xPrize for Carbon Removal

#85

Post by mumblemumble »

mabbo wrote: post #73
BitwiseFool wrote: post #31

Earlier quoted context omitted.

>"Why cant we just plant more trees?" We can, and we certainly should, but that does not solve the problem because those trees will eventually die and that carbon will cycle back through the biosphere. Mankind extracted a ton of carbon from the ground, where it was locked away, and we put it back into the air. People are trying to find ways of putting all that extra carbon back somewhere where it won't affect the cyc…

Well, most of the carbon in the ground that we're burning are long-buried trees, right? I wonder what it would take to just bury a lot of trees and let them regrow naturally. This paper has some interesting ideas: https://cbmjournal.biomedcentral.com/articles/10.1186/1750-0... My approach would be to find the best CO2/$ types of trees, buy them straight from the lumber industry, and sequester them in no-longer-used q…

I'm no chemist, but, wild guess, you might actually make things worse by favoring decomposition into methane instead of CO2.

I would think that a proper solution would require figuring out how to get all that carbon into a chemical form that is chemically stable and won't biodegrade. The ideal looks a whole lot like coal, I'd guess?

Re: $100M xPrize for Carbon Removal

#86

Post by wyager »

krastanov wrote: post #8
wyager wrote: post #3

How is the answer to “carbon removal” not just “turn deserts into plant areas” or “encourage algae blooms” or something? It seems implausible to me that any chemical carbon extraction process has superior externalities to just planting more trees or something.

I do not have a complete well-sourced answer, but the common argument against your suggestion is that such a carbon sink would work for only a couple of decades until it reaches a steady state, and these couple of decades do not seem to be enough to make a dent. Also, it is difficult to plant trees in a desert. Also, algae blooms are dangerous for other life forms. However, there are some startups working with super-…

All fossil fuels were eventually living biomass. I don’t see any reason we wouldn’t “resuscitate” that biomass back into living organisms. It would take a long time for the living biomass to be re-interred into fossil fuels.

Re: $100M xPrize for Carbon Removal

#87

Post by scythe »

filleokus wrote: post #45

I wonder how YC backed Prometheus Fuels will stack up. They claimed that they are able to sequester Co2 directly from the air for around 36 USD / ton [0]. If they truly can scale it at that price point, it seems very competitive. [0]: https://www.prometheusfuels.com/on-the-road/happy-earth-day-...

There are about 2.2 teratonnes of CO2 in the atmosphere. There should be about 1.5 Tt. That's ~700 billion tonnes of CO2 to remove, or about $25tn at your quoted price. Not impossible, but certainly not cheap.

Re: $100M xPrize for Carbon Removal

#88

Post by axaxs »

gruez wrote: post #79
knodi123 wrote: post #61

I wonder if there's any possibilities in engineering a quick-growing trash tree that would have a higher percentage of mineralization, or properties that facilitate quick pseudo-petrification, so that it can be embedded in concrete without worrying about rot. They would serve the same purpose as rebar, but with greater volume meaning less concrete needed. And it would be a near-permanent carbon sink.

That seems much more complicated than just planting some fast growing plant (eg. bamboo), converting it to charcoal, and burying it somewhere. That achieves the same carbon sequestration effect, without having to worry about petrification.

This is exactly what I was thinking. Bamboo has to be one of the fastest growing therefore carbon sucking plants, right?

Re: $100M xPrize for Carbon Removal

#89

Post by wyager »

kisamoto wrote: post #60
wyager wrote: post #3

How is the answer to “carbon removal” not just “turn deserts into plant areas” or “encourage algae blooms” or something? It seems implausible to me that any chemical carbon extraction process has superior externalities to just planting more trees or something.

There is no silver bullet. It has to be a combination of: 1) Reduce emissions to zero (will take some time). 2) Use more natural solutions (trees, algae, kelp etc. - will also take time). 3) Enhance natural solutions with tech (enhanced weathering). 4) Develop carbon capture tech to reverse the damage done by the fossil-fuel burning tech.

Why do we have to reduce emissions to zero? I prefer freeing up carbon from the ground as long as it’s not causing greenhouse heating.

Re: $100M xPrize for Carbon Removal

#90

Post by fy20 »

mabbo wrote: post #73
BitwiseFool wrote: post #31

Earlier quoted context omitted.

>"Why cant we just plant more trees?" We can, and we certainly should, but that does not solve the problem because those trees will eventually die and that carbon will cycle back through the biosphere. Mankind extracted a ton of carbon from the ground, where it was locked away, and we put it back into the air. People are trying to find ways of putting all that extra carbon back somewhere where it won't affect the cyc…

Well, most of the carbon in the ground that we're burning are long-buried trees, right? I wonder what it would take to just bury a lot of trees and let them regrow naturally. This paper has some interesting ideas: https://cbmjournal.biomedcentral.com/articles/10.1186/1750-0... My approach would be to find the best CO2/$ types of trees, buy them straight from the lumber industry, and sequester them in no-longer-used q…

At the time coal deposits formed the bacteria that broke down lingin and cellulose hadn't yet evolved, so just burying trees wouldn't work today as they would decay. You could probably burn the wood to produce charcoal (burning it in a low oxygen environment), and the bury that, but just cutting down a forest and burying it won't work.
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