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by Dylan16807 1014 days ago
> That is the price of a ton of coal. Buy it from China BEFORE it gets burned

And then that money funds more mines to get coal out of the ground faster.

> Sucking it back from the atmosphere AFTER burning takes 10x more energy which is complete insanity.

Part of the plan needs to be capture at power plants. Another part of the plan needs to be heavy taxes for releasing CO2. If someone needs the convenience for some use case, let them pay the capture price.
1 comments
alexey-salmin 1014 days ago
> Part of the plan needs to be capture at power plants.

You realize that this makes power plants energy-negative?

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Dylan16807 1014 days ago
No it doesn't. You're not turning it back into fuel. You need to bottle it up or react it into a non-gas, both of which use much less energy than you get from combustion.
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alexey-salmin 1014 days ago
Well try to write down a concrete chemical reaction to achieve this and you will be disappointed. Light atoms like carbon don't like to stay close to each other at room temperature. You need to pour a lot of energy into chemical bonds between them to make that happen.

So no, it's still an energy-bound problem and we still burn coal to get energy.

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Dylan16807 1014 days ago
One of the options is just injecting CO2 into very deep caves/water. And it will then react with many rocks all by itself!

The company that Microsoft is buying capture from is using lots of energy to remove CO2 from rocks, but that's because they're working to pull more CO2 from normal air. When you have an exhaust pipe it's already concentrated and you can separate it out much more easily.

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alexey-salmin 1014 days ago
Injection of CO2 into water happens naturally in the ocean. Unfortunately ocean didn't respond to any of the VC calls.

Injecting CO2 into rocks "all by itself" is extremely slow because it's exothermic and because surface of rocks is too small. You need to crush the rocks (energy) and heat them up (energy).

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Dylan16807 1014 days ago
> happens naturally in the ocean

That's not fast enough and also risks making the ocean too acidic.

> Injecting CO2 into rocks "all by itself" is extremely slow

By injection I meant injection. Drilling a deep hole and pushing the CO2 out the other end.

Only the reaction happens by itself.

With the right structure underground the CO2 can spread over an enormous surface area at a high concentration that promotes reactions. But even if it that takes too long, each well doesn't need to operate forever.

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