

I don’t question the working principles of DAC, or as you mention separating gasses. It’s just that burning fossil fuels for energy would make no sense if you had to use most, if not all of that energy on DAC. And if you want to use low-carbon energy to power carbon capture, why not use it directly to replace fossil fuels? It seems to me that to reduce net emissions it’s most efficient not to emit it in the first place.
What I mean by entropy is that we burn fossil fuels (low entropy) and release CO2 into the atmosphere (high entropy), so it takes a lot more energy and effort to remove CO2 than simply not burning fossil fuels.
Clearly laws of physics work against us when we try to remove a relatively low concentration gas from a planet-wide system.