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Carbon Removal Technologies

carbon.ycombinator.com

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Re: Carbon Removal Technologies

#51

Post by Tuna-Fish »

ergothus wrote: post #37
kanzure wrote: post #11

Earlier quoted context omitted.

My personal preference is an inflatable sun shield method like these 10,000 kilometer-wide objects: "Self-deployed, extremely large low mass space structures" http://diyhpl.us/~bryan/papers2/space/Self-deployed%20extrem... I don't think people realize how a lot of these problems are solvable for only a few billion dollars... It's an engineering problem, mainly. Someone just spends the money and goes and fixes the pro…

I'm skeptical - You've shown a proposal, not a reality. (and the proposal didn't even mention a "shield" that I saw, but I may have skimmed past it). I didn't see a price tag, nor a timeline. Money can boost research speed, but not remove the need entirely. Second, If the cross section of the earth is 1.2x10^14 m^2, one of these would...well, we don't know, because the link mentioned volumes and length (the 10k km is…

> Third, and most importantly, you've just decreased the amount of energy coming to earth. You've not solved the problem, you've changed it.

Probably the most important advantage sunshades have over other kinds of geoengineering megaprojects is that they can be trivially (compared to their construction costs, that is...) turned off. If they turn out to be very harmful in some previously unforeseen way, we can choose to not have them anymore.

That is not so for, for example, seeding lots of nutrients for algae over the continental shelf.

Re: Carbon Removal Technologies

#52

Post by JumpCrisscross »

mdorazio wrote: post #27
GreeniFi wrote: post #2

We already have carbon removal technology. They’re called trees. [Edit] I’m not being facetious. 40% of emissions are as a result of poor land management. We’ll need all the technological help we can get, but if we can’t manage land as carbon stores - not sources, we’re not going to win this race.

This is covered in the "Where We Are Now" section at the bottom that explains BECCS. The issue is really cost - to remove carbon semi-permanently with trees you have to grow a lot of them, and then bury them deep enough that natural decay processes don't just put the carbon back into the environment. Basically you have to do the exact opposite of what we've been doing with coal and oil for over a century.

> Basically you have to do the exact opposite of what we've been doing with coal and oil for over a century

There's a nugget of a story in the Carboniferous being the result of a civilisation trying, but failing, to sequester carbon by burying trees and plankton.

Re: Carbon Removal Technologies

#53

Post by Symmetry »

Retric wrote: post #26
WhompingWindows wrote: post #5

Can we discuss space sunshades? Assuming the cost of getting freight to orbit goes down substantially as companies like SpaceX ramp up launches, what's the limiting parameter on some sort of sunshade over the north and/or south pole? Is it indeed the cost of launching the sunshade, or are there other factors at play which make the space sunshade unrealistic? What materials would be reflective and resilient and cost-e…

Because the earth is effectively a black body it cools down at T in kelvin^4. This means you need to block a huge amount of energy ~2% of the sun to get around global warming. Sticking something at L1 looks elegant, but you cant just toss junk there it needs serious station keeping making it far more expensive than many assume. PS: Unfortunately, as a side effect you reduce the energy of all plant life by ~2% solar p…

The launch volume looks infeasibly large in the foreseeable future, but I don't think the station keeping problem is that bad. Any sun shade is basically going to be a solar sail already and steering via LCD panels like IKAROS did should be sufficient.

https://en.wikipedia.org/wiki/IKAROS

Re: Carbon Removal Technologies

#55

Post by Symmetry »

GreeniFi wrote: post #2

We already have carbon removal technology. They’re called trees. [Edit] I’m not being facetious. 40% of emissions are as a result of poor land management. We’ll need all the technological help we can get, but if we can’t manage land as carbon stores - not sources, we’re not going to win this race.

Trees will only absorb 1 watt of hydrocarbon emissions per square meter, on average, even before considering the cost of burying the woods so the carbon isn't released when it rots.

Re: Carbon Removal Technologies

#56

Post by sandworm101 »

kanzure wrote: post #11
WhompingWindows wrote: post #5

Can we discuss space sunshades? Assuming the cost of getting freight to orbit goes down substantially as companies like SpaceX ramp up launches, what's the limiting parameter on some sort of sunshade over the north and/or south pole? Is it indeed the cost of launching the sunshade, or are there other factors at play which make the space sunshade unrealistic? What materials would be reflective and resilient and cost-e…

My personal preference is an inflatable sun shield method like these 10,000 kilometer-wide objects: "Self-deployed, extremely large low mass space structures" http://diyhpl.us/~bryan/papers2/space/Self-deployed%20extrem... I don't think people realize how a lot of these problems are solvable for only a few billion dollars... It's an engineering problem, mainly. Someone just spends the money and goes and fixes the pro…

>> for only a few billion dollars.

Really? This isn't just a matter of putting a big ball of tin foil out there letting it go. What about the station keeping? How is this big piece of tinfoil going to stay in place? At these sizes, solar pressure and the buildup of static charges become huge issues. It is going to drift. It will need engines, power and fuel. Ion thrust would seem an obvious answer, but electrical/static issues may make a web of ion drives difficult. It will need either new tech or, at least, extensive testing of current tech before any attempt. = a great many billions of dollars. I'd rather see that money spent on solar panels.

Re: Carbon Removal Technologies

#57

Post by lchengify »

For anyone who is interested in the Energy Industry in general, including Carbon Capture (CCS), I would recommend "The Energy Gang" podcast as well as "The Interchange".

The guys who run the podcast are not long on CCS as a savior for 1.5 degrees C, but they are incredibly knowledgable about the space and dive into a lot of technical, policy, and economic minutiae that you wouldn't think would exist.

I never exactly knew how much mitigating something like peaker plant composition and more sophisticated demand response can affect existing CO2 emissions. Even things like the opinions of energy executives in the (very silo'd) regional utilities (Dominion Energy, Green Mountain Power, etc) can have a wide-reaching effect on the timeline of policy.

I've listened to the whole run of each of the podcast and it's definitely got me more excited about the space. I'm glad YC is getting more aggressive.

Re: Carbon Removal Technologies

#58

Post by guelo »

An elephant in the room not being discussed here are the propaganda networks that are persuading voters and preventing any kind of government action on climate. Disrupting these propaganda businesses is another necessary angle of attack for preventing climate change catastrophe.

Re: Carbon Removal Technologies

#59

Post by btilly »

I would strongly suggest investigating the claims of http://www.innovationconcepts.eu/res/literatuurSchuiling/oli... that after mining, milling, and then being spread in the ocean, olivine rocks weather quickly and take out CO2. The estimated costs of large scale CO2 sequestration this way are surprisingly reasonable, and the technology is already available.

Also the various ocean technologies are going to run into the same environmental complaints as the idea of seeding otherwise barren areas of the ocean with missing metals, causing algae blooms that sink to the bottom. See https://www.scientificamerican.com/article/iron-dumping-ocea... for a discussion of some of those. (And see https://www.forbes.com/sites/timworstall/2014/04/28/iron-fer... for a more laudatory article about this in the general press.) If you can deal with the regulatory concerns, the existing low-tech solution is one of the cheaper ways of removing CO2 that is known.

Speaking personally, I understand the qualms of environmentalists but consider the possibility of local toxic algae blooms to be a less serious environmental disaster than the otherwise certain ocean acidification that will wipe out all shellfish species worldwide. Yeah, nobody wants to accept a bad outcome, but in this case I think it is better than the alternative.

Re: Carbon Removal Technologies

#60

Post by JumpCrisscross »

godzillabrennus wrote: post #36

YC should be investing in Deep Isolation. http://deepisolation.com

You're being down voted because this is off topic. One, the threat from nuclear waste pales in comparison to that from climate change. Two, making nuclear energy more attractive reduces emissions. This article is about removing carbon from the atmosphere.
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