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$100M xPrize for Carbon Removal

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Re: $100M xPrize for Carbon Removal

#271

Post by PeterisP »

wyager wrote: post #83
sevenf0ur wrote: post #33

Earlier quoted context omitted.

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.

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 biomass than the Earth has now or has had at any particular moment of history.

Re: $100M xPrize for Carbon Removal

#272

Post by bognition »

Arete314159 wrote: post #246
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 decade sounds like a pretty good start. If we could combine that with transitioning away from lawns and towards gardens / orchards (like even on highway medians!), imagine the savings in terms of shipping food.

Highway medians are lawn for safety reasons. Planting an orchard between two lanes of traffic going 75 mph would result in a ton of fatalities

Re: $100M xPrize for Carbon Removal

#273

Post by abathur »

Dylan16807 wrote: post #269
abathur wrote: post #263

Earlier quoted context omitted.

This comment makes me think you may reading me differently than I intend, though I'm not sure which bit you're responding to. Perhaps my use of the word "operators"? In any case, I do not intend to suggest any subsidy to fossil fuel producers, here. When I say operators, I mean the operators of capture operations. The only context in which I intentionally point to producers is around the possibility that they might a…

You quoted someone talking about not-pumping oil as part of your line about subsidies. That's on the production side.

Yes. @knodi123 is joking about fraud. I am talking about fraud.

Re: $100M xPrize for Carbon Removal

#274

Post by detritus »

Mizza wrote: post #264
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…

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 farm waste, etc.

Re: $100M xPrize for Carbon Removal

#275

Post by Robotbeat »

jpalomaki wrote: post #234
foobarian wrote: post #231

Earlier quoted context omitted.

Do trees actually help? AFAIK once a forest reaches equilibrium it puts out as much CO2 as it takes in through various decomposition processes.

Using more wood as construction material helps to tie the CO2 for longer period.

This. Early trees sequestered a whole bunch of carbon in their structure (and there wasn’t efficient methods of breaking down lignin at the time, so the carbon stayed in the ground instead of rotting and returning to the sky). If we build long-lived structures out of wood or other carbon bearing materials whose carbon source is the atmosphere, we’ll be doing the same thing as trees but with human civilization as the organism.

Re: $100M xPrize for Carbon Removal

#276

Post by PeterisP »

wyager wrote: post #89
kisamoto wrote: post #60

Earlier quoted context omitted.

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.

Well, it is causing greenhouse heating, that's the whole point, any freeing up carbon is inherently linked to that. But it is more appropriate to say that we have to reduce net emissions to zero; there would be no problem with emissions if there's a compensating carbon capture of equal amount. At least after we've "paid back the debt" by recapturing the excess emissions of earlier decades - there needs to be some period of negative net emissions before zero net emissions would be okay.

Why do you prefer "freeing up carbon from the ground" ? Usually that's just a sideeffect that happens only because we want some other thing e.g. extract energy from oil or manufacture cement by calcinating limestone; and if we want a stable atmosphere then we can't be freeing up carbon from the ground without putting it back.

Re: $100M xPrize for Carbon Removal

#277

Post by Robotbeat »

rcpt wrote: post #200
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…

It does seem unlikely that we'd be able to control temperatures without resorting to sulfur dioxide. It'll probably start a war, but once natural resources start getting scarce I fully expect the affected nation to deploy SO2.

I don’t think you should be downvoted. People really don’t like it because it is clearly not the optimal way to solve the problem, but we should take the possibility seriously instead of down voting anyone who brings it up as something that might happen.

We are letting anthropogenic global warming happen because it’s cheaper in the very near term. But climate change is a real thing and will have real, life-threatening effects especially for some geographic regions.

If we accept the reality that: 1) humans often just do what is cheapest and easiest even if the long-term consequences are bad AND 2) global warming will start killing massive numbers of people from things like heat stroke, putting enormous political pressure on governments to do something,

…then The logical conclusion (combined with how insanely cheap SO2 is to deploy, we’re talking maybe $50 billion a year, maybe less) is that there is an extremely high probability that some nation will just unilaterally do sulfur dioxide. Think of a Nation like India, with a large population that will be vulnerable to heat stroke and a big enough budget and military to just unilaterally do something like this to stop the political unrest of hundreds of thousands of heat stroke deaths per yearz

Re: $100M xPrize for Carbon Removal

#278

Post by otterley »

m12k wrote: post #254
otterley wrote: post #196

Earlier quoted context omitted.

Dead trees lie on the ground, with all their sequestered carbon sitting there. It's not like the carbon is going back into the atmosphere, at least not without some process like combustion. Coal is basically dead trees. Before we started extracting coal and burning it, it was harmless to the atmosphere.

Doesn't rotting, or being eaten by microbes or termites that eventually get eaten or die and rot eventually lead to the release of the stored carbon? AFAIK coal is composed mostly of trees that fell back before microbes evolved that could eat through their cellulose walls, and have had millennia of underground compression to further increase their stability - basically that process isn't available naturally to trees…

It takes roughly twice as long for a tree to decompose as it does to grow; and trees live a lot longer than that! So over time, the net sequestration should be positive.

Re: $100M xPrize for Carbon Removal

#279

Post by Robotbeat »

usefulcat wrote: post #147
songzme wrote: post #110

Earlier quoted context omitted.

Trees do much more than remove carbon from the air. Carbon removal machine could potentially create c02 deficit regions, creating hostile environments for trees. We can't possibly build a machine for every function a tree does.

> Carbon removal machine could potentially create c02 deficit regions, creating hostile environments for trees. If we could remove so much CO2 from the air that it prevented plants from growing (even if the effect were highly localized, which is pretty much a certainty), then we might actually have a shot at being able to remove CO2 in a reasonable amount of time. So this definitely sounds like a good problem to have…

CO2 is pretty well-mixed and it takes a lot of energy to pull CO2 out so it is unlikely to be the primary method of address Climate change. Also at this point we are substantially above the pre-industrial level of CO2 so there’s essentially no chance of having CO2 poor regions.

Re: $100M xPrize for Carbon Removal

#280

Post by highenergystar »

It seems like the only things that can 1. work at a planetary scale 2. mitigate our multi-year (and growing) emission problem 3. not on an energy flywheel (consume a significant amount of energy, mined resources or themselves emit significant waste heat)

have to rely directly on solar energy (not intermediated by PV cell). To this end azolla ferns [1] and olivine weathering seem to be the most promising.

[1] https://en.m.wikipedia.org/wiki/Azolla_event

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