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$100M xPrize for Carbon Removal

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Re: $100M xPrize for Carbon Removal

#91

Post by krastanov »

soperj wrote: post #51
nostromo wrote: post #30

Earlier quoted context omitted.

Productive forests in the US are a carbon sink. The trees grow. We cut them down. We make houses out of them, which are wrapped to prevent deterioration. The sunk carbon becomes our buildings. Other uses of the wood are also usually carbon sinks. Paper either gets recycled (the carbon is preserved) or it gets buried in a sealed landfill where is takes decades or longer to break down. It'd be cool to calculate how muc…

Wouldn't it break down into methane instead though? I doubt that building buildings are carbon neutral, let alone a carbon sink.

Dried up wooden building material is pretty stable and a fairly common (even commercialized) suggestion for a carbon sink. If you let it rot/burn, then no, it is not a carbon sink.

Re: $100M xPrize for Carbon Removal

#92

Post by BitwiseFool »

wyager wrote: post #80
BitwiseFool wrote: post #12

Earlier quoted context omitted.

All the fossil fuels we've been burning is introducing carbon back into the biosphere. The key to carbon removal is to sequester it back somewhere where it won't be circulating in nature. It's not enough to plant more trees, as those new trees' carbon will just continue to cycle through the environment.

Why do I want to prevent carbon from circulating in nature? I like plants and animals and I want more of them.

The main problem is that we've released so much, so fast, that there really isn't a productive place for it to go. The other problem is that humanity keeps expanding and there's not much free space left for nature preserves. If you wanted to plant a new rainforest, where would you possibly put it? We're already cutting down swathes of existing ones just to feed and house our expanding populations. So sadly, most of that extra carbon just remains in the air.

Re: $100M xPrize for Carbon Removal

#93

Post by smoovb »

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.

Yes, it's called bamboo and it sequesters 3x the carbon and grows to maturity 10x faster than a normal forest (3 years vs 30 years). And bamboo has some of the qualities of rebar, so should mix nicely with concrete. Of course it is best grown in tropical regions, hence why most of the talk here is about trees.

Re: $100M xPrize for Carbon Removal

#95

Post by kisamoto »

tekstar wrote: post #62
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…

Also, planting trees sequesters co2 into the biosphere. That is not good enough, we need to be sequestering co2 into the geosphere if we want to remove it from the equation

Naturally (without human influence) a combination of biosphere (decades) and geosphere (millenia) would keep CO₂ levels in check.

We (humans) have accelerated emissions (by burning, thus reversing, geosphere capture via oil) and destroyed the biosphere through deforestation. This has also been accelerated as raising temperatures thaw permafrost & destroy ocean life (among others).

Anything we can do to reverse this is beneficial.

Re: $100M xPrize for Carbon Removal

#96

Post by abeppu »

This sounds cool from a tech-nerd perspective, but of course it all is pretty futile if we don't get emissions under control. The video says 10 gigatons/yr by 2050. Our 2019 emissions were ~36 gigatons. I.e. even if capture is successful, it needs to be accompanied by aggressive emissions reductions for us to even get to neutral, let alone reversing damage.

I'm guessing Musk had some thought process around the expected marginal impact of funding this vs more on energy storage vs energy production. And perhaps capture/sequestration is under-explored.

But I wonder what could be achieved with $100M of funds directed at research to intentionally changing and shifting culture towards consuming stuff with smaller footprints? Tesla made some people want an electric car really badly. For some, very small houses are becoming attractive. But so far this stuff mostly arises from ad-hoc marketing efforts around particular brands, products, influencers. What if we need systematic memetic engineering, to make lower energy consumption actually feel desirable?

Re: $100M xPrize for Carbon Removal

#97

Post by abathur »

I don't mean to be a wet blanket (I imagine the prize will be a net good) but I want to talk into the void about something I've been befuddled by...

I feel like I see/hear a lot of uncritical faith in (techno|market|competition)-solutions, with little discussion of what Nth-order effects may travel with those approaches. Just some scattered thoughts:

- The best case for progress is probably technology that leads to profitable unsubsidized capture, but incremental technological progress may give the industry that springs up around it profit motives to overshoot.

- Profitable capture would, if fossil-fuel producers get in on the action themselves, shift their break-even points around somewhat.

- Even if this operates at a loss and depends on public funding, if the work is done by private industry and not the public sector, a few decades of capture may avert/blunt the crisis but leave us with yet another powerful lobby. It'll likely be flush with good-will and hard to regulate, let alone wind down once it has served its use.

- As @knodi123 puts it: "I can not-pump 100M of oil in my own back yard. And you wouldn't believe the rate I can not pump it at!" If all of the operators depend on subsidy, there will be a decent incentive towards graft/corruption/fraud. There'll have to be some amount of administrative overhead going to verifying what is captured, that it isn't double-counted, that it actually gets sequestered, and so on. A deepening crisis could mean more of this money sloshing around and less will to build the compliance mechanisms that ensure it accomplishes the goal. Rampant graft could be enough to sink the program.

Re: $100M xPrize for Carbon Removal

#98

Post by Andrew_nenakhov »

scythe wrote: post #87
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.

At that scale, the price per ton would probably drop by a factor of 5-10 or more, so it looks quite doable.

Re: $100M xPrize for Carbon Removal

#99

Post by giantg2 »

BitwiseFool wrote: post #7
giantg2 wrote: post #2

Time to quit my job and become an inventor (actually something I thought was a real thing when I was a kid). My idiot-layman brain says buy it from AirGas or capture from large emitters and pipe it into a geological structures like the do for storing helium. It could probably only get to gigatons if it's worldwide and we have enough geological structures capable of containing it.

I thought the same thing as a child. Recently I realized that programming and making apps is like being an inventor. When I make applications for other people to use, is that not akin to making some kind of new machine or tool?

I don't really see it the same way. I mean, as an independent project, maybe. Most of us are basically told what to build and largely how to build it too. Someone else invented it and we just build it - we're basically factory workers.

Re: $100M xPrize for Carbon Removal

#100

Post by knodi123 »

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.

It certainly is more complicated. The difference is that

1.) it attacks three different problem sources - the carbon already in the air, and the carbon generated by concrete production, and the carbon from steel production. Cement is responsible for about 8% of global CO2 emissions [1], and steel another 8% [2].

2.) it offers profit incentives, since the people using the trees get a direct benefit (unlike people throwing biochar into an ocean trench). Any long-lasting solution to our carbon problem is going to have to find a way to exist on something other than direct carbon-dedicated subsidies. A self-sufficient business can survive shifting political winds much better than a literal money-sink.

[1] https://www.bbc.com/news/science-environment-46455844

[2] https://www.mckinsey.com/industries/metals-and-mining/our-in...

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