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by lucb1e 1807 days ago
> carbon sequestration [will] likely require energy

Yes, but that doesn't mean we won't need it.

Take air planes. We can't just put batteries in there: too low energy density or something (I'm no physicist, but they won't fly very far is what I gather). But by capturing the CO2 (at exhaust, or atmospherically) that they put out, we can have both airplanes and a stable climate -- assuming it's all done right.

Who wants to have a wind turbine in their back yard? A nuclear power plant? Who lives near that hydro plant in the middle of nowhere? We could instead capture CO2 away from people if power is cheap, before sending the rest down a slightly lossy transmission path.

Driving regular passenger vehicles electrically is definitely less energy intensive than capturing the GHGs that a combustion engine produces, so it would obviously be counter-productive to use capture technology for those sorts of things. But we can use it for other things like chemical processes that produce a GHG as a byproduct where it's hard to capture (new buildings using concrete, for example) or when we don't have the technology to get rid of the emissions.

Right now, the quickest wins are from emission reduction. This capture technology is something we need to have ready for the next phase of keeping our natural habitat stable.

3 comments

> Who wants to have a wind turbine in their back yard?

Here in Los Angeles we have honest-to-god oil derricks in our neighborhoods and the NIMBYs don't even notice. Apartments OTOH...

I went to a wind turbine some time because I was curious how loud it would be. It doesn't seem that loud actually. Maybe it's more the looks? (Personally, it's not that terrible and, well, we don't have a choice so define some nature reserves and for the rest go ahead.) Either way, I meant it more in the proverbial NIMBY sense rather than that literally everyone feels the same way about them.
> Take air planes. We can't just put batteries in there: too low energy density or something

Actually for completion it is a feasible proposal [0] (Obviously not for jet propulsion though).

[0] https://www.airbus.com/innovation/zero-emission/electric-fli...

One of the more exciting things in green aviation is "air to fuels". There are companies working on converting atmospheric carbon into hydrocarbons for storage (using renewable energy). Those hydrocarbons can then be used as jet fuel, so it's isn't carbon-negative, but at least it's carbon-neutral. Any hydrocarbons left over that are stored are carbon-negative.
Ack, I know of those. Isn't that the same thing as carbon capture? It also uses more energy to capture the carbon than the fuel will produce after burning. Just that the output is usable fuel (yay put it back in the atmosphere ^^' but better burning circular than burning fossil fuels) rather than rocks like Climeworks and Olivine output.

I never actually saw anyone compare the options. Anyone know if it's cheaper (or less energy-intensive) per ton of CO2 to turn atmospheric CO2 into rock and continue using fossil fuels for another century until oil really starts playing hard to get, or if it's cheaper (or less energy-intensive) to use this air-to-fuel technology?