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$100M xPrize for Carbon Removal

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Re: $100M xPrize for Carbon Removal

#311

Post by detritus »

wanderingmind wrote: post #306
detritus wrote: post #274

Earlier quoted context omitted.

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 co…

Start making it in Egypt or Tripoli?

People in deserts shit too, I think.

Re: $100M xPrize for Carbon Removal

#312

Post by flavius29663 »

lucb1e wrote: post #297
flavius29663 wrote: post #197

Earlier quoted context omitted.

it's actually 36 - (36x0.25) - (36x0.25) - 10 = 8. But yeah, we would have to reduce our emissions by at least 8GT to get to zero. That is totally doable, advanced economies are already reducing CO2 at a faster rate than 25% over 30 years: the US has reduced it's emissions by 1GT in 10 years (16% reduction).

If you absorb 25% (you wrote "plants absorb about 25%" and same for trees), then 75% remains, so apply ×0.75 twice instead of applying ×0.25 twice.

but that's not how it works...plants absorb a quarter of total emissions and the oceans about a quarter too. So half the emissions are absorbed, and half are not.

Re: $100M xPrize for Carbon Removal

#313

Post by wanderingmind »

There seems to be no target beyond the amount of carbon to capture. Are they targeting for $ per tonne removal. Efficiency of removal? Climeworks already has technology that has removed more than 1000 tonnes of Carbon from atmosphere(0). Can we just give them the price? The trouble is cost. Climeworks estimates that at scale their tech would cost $500 - $600 per hour. Looks like this is still high and the current wisdom is that we need to bring it down to $100 per tonne from atmosphere. Also I think removing directly from power plant exhaust is probably a better approach that trying to shoot for a technology that sequesters from atmosphere.

(0) https://www.nytimes.com/2019/02/12/magazine/climeworks-busin...

Re: $100M xPrize for Carbon Removal

#314

Post by lovemenot »

schiffern wrote: post #304
fooker wrote: post #224

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. 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…

>> Anyone still think it's a good idea to utilize all that "valuable real estate" being "taken up" by trees?

As long as plantation owners and/or illegal loggers do, then all your argumentation is moot.

Re: $100M xPrize for Carbon Removal

#315

Post by pinkrobotics »

detritus wrote: post #256

Soil. It's soil. Soil, in prodigious quantities. We need to be making it. Using human waste - food and faecal from our cities; Using whatever plant fixes the most CO2 in a useful form that we can turn into charcoal (quick trees? bamboo grass? something genetically modified?), releasing heat energy, and then fixing carbon in a useful matrix, for soil regeneration a la Terra Preta. I sort of made this post elsewhere he…

Soil could be something that is too easily overlooked.

If you had prodigious quantities of good soil, you could grow trees and food at sea, where we have lots of space to grow, especially at the equator.

The problem then becomes a floating platform, and controlling it all, but those seem less difficult.

Re: $100M xPrize for Carbon Removal

#316

Post by jtsiskin »

This is funny. There is one group of people pumping carbon out of the ground and burning it. Then there is another group of people capturing the carbon and putting it back into the ground.

I'm picturing a power plant burning coal, then a windmill farm next to it powering a carbon removal process. I guess the potential power generation offset must be accounted for, even if in the solution it's coming from renewable resources.

The solution really seems to be to burn less of it in the first place.

Re: $100M xPrize for Carbon Removal

#317

Post by Texasian »

jtsiskin wrote: post #316

This is funny. There is one group of people pumping carbon out of the ground and burning it. Then there is another group of people capturing the carbon and putting it back into the ground. I'm picturing a power plant burning coal, then a windmill farm next to it powering a carbon removal process. I guess the potential power generation offset must be accounted for, even if in the solution it's coming from renewable re…

Yeah, this is the carbon equivalent of trying to get abs by working out more without adjusting your diet.

Re: $100M xPrize for Carbon Removal

#318

Post by wpasc »

jtsiskin wrote: post #316

This is funny. There is one group of people pumping carbon out of the ground and burning it. Then there is another group of people capturing the carbon and putting it back into the ground. I'm picturing a power plant burning coal, then a windmill farm next to it powering a carbon removal process. I guess the potential power generation offset must be accounted for, even if in the solution it's coming from renewable re…

Despite plenty of wasteful use of carbon, energy use largely correlates with reduction in extreme poverty, hunger, etc. Energy use is a requirement for most societies and for people to alleviate basic human needs.

I'm not saying we shouldn't try to be maximally efficient and renewable in our energy usage, but often times a reduction in energy usage requires a loss of functions that improve people's lives.

Re: $100M xPrize for Carbon Removal

#319

Post by Mizza »

flavius29663 wrote: post #312
lucb1e wrote: post #297

Earlier quoted context omitted.

If you absorb 25% (you wrote "plants absorb about 25%" and same for trees), then 75% remains, so apply ×0.75 twice instead of applying ×0.25 twice.

but that's not how it works...plants absorb a quarter of total emissions and the oceans about a quarter too. So half the emissions are absorbed, and half are not.

I think you're making a very common mistake, which is misunderstanding the carbon cycle.

We could, theoretically, grow enough plants to get down to pre-industrial levels. However, plants decompose when they die, re-releasing their carbon into the atmosphere, and lots of the plants alive to die are grown using petrochemical fertilizer, which was taken from under the ground, not the atmosphere.. So, we'd have to keep all of those new plants alive, forever, or maintain that extreme level of plant growth forever. This seems like an even harder problem.

Re: $100M xPrize for Carbon Removal

#320

Post by blurbleblurble »

burgessaccount wrote: post #259
kisamoto wrote: post #56

There's a few "plant trees" or "terraform the sahara" comments in here. For some context, if we planted trees wherever we could around the world we can only undo a decades worth of emissions[0]. Not only that but it would still take a century for the trees to reach maturity. Our use of technology threw nature out of balance and we need to use technology to get the balance back again. [0] https://science.sciencemag.or…

A few other problems - 1) trees take a lot of water to grow, and 2) all the carbon they sequester can go right back into the atmosphere in a forest fire. Some very scrupulous carbon-offset companies (like YC co terraformation!) are careful to plant diverse, native species in a way that rebuilds habitat and fits local water supplies. But there are a huge number of irresponsible tree-planting orgs that plant monocultur…

Trees take a lot of water to grow but they also hold water and share it through the air and ground with other plants and with other creatures in the form of transpired water vapor.
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