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A CO2 capture solvent with exceptionally low total costs of capture

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Re: A CO2 capture solvent with exceptionally low total costs of capture

#72
post #36

Earlier quoted context omitted.

"The plants and animals will adapt and evolve to handle the additional heat" Evolution takes thousands of years. In that time species will go extinct, so there is no chance for them to evolve. For a simple demonstration of how fast we are changing the climate compared to other periods when ecosystems may have been able to adapt, see https://xkcd.com/1732/

>> Evolution takes thousands of years Not true. Natural selection can work its magic in a single generation. For example, given any normal population, choose any trait and remove all individuals which have this trait from the population. The next generation will not have this trait. Specimens with the trait will become extremely rare depending on how accurate the selection process was. It can be quite radical. For ex…

Yeah, because there exist short humans and so their genes would indeed be passed on. Now check that for all organisms relevant to our food chain (assuming we even know which ones those are, and assuming we only care for ourselves and the rest can go extinct) there is a sufficient number of individuals in the relevant places able to cope with droughts, heat waves, flooding, storms, and other extreme weather introduced in the new climate.

It doesn't magically just solve itself, even if that's the easiest thing to tell yourself and look for confirmation bias for.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#73

Earlier quoted context omitted.

>I feel like CO2 sequestration is second only to nuclear in the amount of unfounded concerns The problem with CO2 capture specifically (specifically from the atmosphere as opposed to at the source) is that CO2 comprises a very small part of air. This means you have to move huge amounts of air through a capture device to capture a very small amount of carbon. How is that ever going to make sense?

It makes sense because brute force engineering solutions are frequently the right ones. If you capture carbon from the air, you can mass produce one kind of capture facility and spam as many copies of this facility as you need (at low cost, thanks to mass production) to give humanity closed-loop control over atmospheric composition. If you rely on source emissions control only, you need finnicky source-specific insta…

Remember those facilities would have very high running costs (energy usage), it's not just a case of building them.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#74

Earlier quoted context omitted.

1. The solvent in carbon capture runs in a closed loop. You typically heat it, and it releases the CO2 so you can compress it and inject it below ground. 2. You don't necessarily need a depleted natural gas reservoir to inject CO2 subsurface (though they sure are convenient) and there is plenty of room for CO2 subsurface. It also doesn't creep to the surface on any meaningful timescale. 3. How do we transport it ther…

$50 per tonne? A coal plant produces about a tonne of CO2 for every MWh produced. Industrial electricity price might be $50 per MWh. So just paying for the carbon capture doubles your electricity price? $100 carbon capture charge would triple it. I can't see how this could be competitive. We have an excellent carbon storage technology, it's called coal. And what's best, it's already there, underground, very safely, p…

Co2 pricing is not the only way though. You could give co2 capturing gas peakers a strike price in the same way as renewables. Or have a capacity market that is only open to carbon capturing energy sources.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#75

Earlier quoted context omitted.

1. The solvent in carbon capture runs in a closed loop. You typically heat it, and it releases the CO2 so you can compress it and inject it below ground. 2. You don't necessarily need a depleted natural gas reservoir to inject CO2 subsurface (though they sure are convenient) and there is plenty of room for CO2 subsurface. It also doesn't creep to the surface on any meaningful timescale. 3. How do we transport it ther…

$50 per tonne? A coal plant produces about a tonne of CO2 for every MWh produced. Industrial electricity price might be $50 per MWh. So just paying for the carbon capture doubles your electricity price? $100 carbon capture charge would triple it. I can't see how this could be competitive. We have an excellent carbon storage technology, it's called coal. And what's best, it's already there, underground, very safely, p…

Double the price of coal sounds like an excellent thing!

Still very cheap. Promotes better sources of energy.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#76

For making a dent in global warming we'll need to have billions of tonnes of this "N-(2-ethoxyethyl)-3-morpholinopropan-1-amine (2-EEMPA)" stuff.. I wonder if this won't be an environmental hazard in itself. What do we do with it after it's captured its CO2? We can't just dump that stuff in the sea. I wonder if CO2 capture does not cause more problems than it solves. Even if we magically could capture CO2 as pure car…

"just reduce our energy usage" has been the plan for decades, and it's easier said than done. Also:

"Our hardest climate problems – the ones that are both large and lack obvious solutions – are agriculture (and deforestation – its major side effect) and industry. Together these are 45% of global carbon emissions. And solutions are scarce."

https://techcrunch.com/2019/02/15/how-to-decarbonize-america...

At the very least I think carbon capture makes sense for the long tail of industrial processes where the "CO2 emission" to "cost of reinventing process" ratio starts to get less and less favorable.

But even if you think we can decarbonize every last industrial process, we might as well develop carbon capture in case too much carbon gets emitted before that goal is achieved.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#77
post #36

Earlier quoted context omitted.

"The plants and animals will adapt and evolve to handle the additional heat" Evolution takes thousands of years. In that time species will go extinct, so there is no chance for them to evolve. For a simple demonstration of how fast we are changing the climate compared to other periods when ecosystems may have been able to adapt, see https://xkcd.com/1732/

>> Evolution takes thousands of years Not true. Natural selection can work its magic in a single generation. For example, given any normal population, choose any trait and remove all individuals which have this trait from the population. The next generation will not have this trait. Specimens with the trait will become extremely rare depending on how accurate the selection process was. It can be quite radical. For ex…

That's not natural selection, that's artificial selection.

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

Re: A CO2 capture solvent with exceptionally low total costs of capture

#78

Earlier quoted context omitted.

1. The solvent in carbon capture runs in a closed loop. You typically heat it, and it releases the CO2 so you can compress it and inject it below ground. 2. You don't necessarily need a depleted natural gas reservoir to inject CO2 subsurface (though they sure are convenient) and there is plenty of room for CO2 subsurface. It also doesn't creep to the surface on any meaningful timescale. 3. How do we transport it ther…

> I also happen to think a $100 per tonne carbon price is not such a bad idea. Government here in Norway recently released their climate plan, and part of it was the gradual increase to 2000 NOK (~234 USD) per tonne of CO2 in 2030[1]. Not sure if it survives the years of politics between then and now though... [1]: https://www.dn.no/politikk/erna-solberg/sveinung-rotevatn/kl...

Does this include the carbon ultimately released from oil that was sold to other countries by Norway?

Re: A CO2 capture solvent with exceptionally low total costs of capture

#79

Earlier quoted context omitted.

> to use the climate as a pretext to reform everyone's lifestyle and to roll back industrial civilization more generally. Not roll back. But do smarter. It's not just global warming. We're shipping billions of tons of stuff from one side of the planet to another in sulphur-blowing rustbuckets. Creating continents of floating plastic in the oceans. Causing toxic lakes from harvesting rare earth minerals. We can't keep…

> We can't keep doing this In the broadest possible sense, no, we can't keep doing "this": either we limit fertility somehow or we got the Malthusian limit eventually. That's just the consequence of the exponential function. And right now, whether population will stabilize on its own before we hit carrying capacity is an open question. But if you hold population constant? Yes, we can keep doing this indefinitely, or…

Right now most population models suggest we'll see growth flatten within decades, and peak within a century.

It's not really an open question - it would take reversal of long lasting trends in large parts of the world to do more than at most delay the reversal.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#80

For making a dent in global warming we'll need to have billions of tonnes of this "N-(2-ethoxyethyl)-3-morpholinopropan-1-amine (2-EEMPA)" stuff.. I wonder if this won't be an environmental hazard in itself. What do we do with it after it's captured its CO2? We can't just dump that stuff in the sea. I wonder if CO2 capture does not cause more problems than it solves. Even if we magically could capture CO2 as pure car…

1. The solvent in carbon capture runs in a closed loop. You typically heat it, and it releases the CO2 so you can compress it and inject it below ground. 2. You don't necessarily need a depleted natural gas reservoir to inject CO2 subsurface (though they sure are convenient) and there is plenty of room for CO2 subsurface. It also doesn't creep to the surface on any meaningful timescale. 3. How do we transport it ther…

Maybe you can help enlighten me on this. I've been struggling to understand the basics thermodynamics of carbon capture for quite some time.

So we have a hydro-carbon, we mix it with oxygen, and the oxygen combines with the hydrogen and the carbon, and releases heat as a byproduct. The heat energy increases the pressure of the newly created CO2. This higher pressure is placed on one side of a turbine or a piston, and we extract useful work by moving it from a high density state to a low density state, causing it to cool in the process.

Now it seems like if you want to re-concentrate that CO2, it should take at least as much work to compress it back to its original size as it released when you burned it in the first place, and probably a lot more, because the CO2 has been diffused into the general atmosphere.

To state it more succinctly, we extract work through a pressure differential, and by reversing that pressure differential, won't that require more work than we got out in the first place by the second law of thermodynamics?

I ignored the part where part of the energy is coming from the hydrogen. Is the hydrogen -> water where most of the energy is coming from, and the carbon part relatively insignificant?

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