[jiggawatts]

Plants do it using the energy from the sun.

All of these “can’t we just unburn burnt things” forget that the reason we burnt the carbon in the first place was to get that energy.

Unburning it would need to return that energy and more because of inefficiencies.

If you have energy to spare, you don’t need to burn the carbon in the first place.

With global fossil fuel usage still rising, we clearly don’t have any to spare.

[glial]

It's not so clear to me -- the MIT Technology Review is already wringing its hands about energy being so cheap it causes problems with economics.

[1] https://www.technologyreview.com/2021/07/14/1028461/solar-va...

[doctorwho42]

Energy can be economically cheap in the current paradigm, while also being insufficiently cheap or insufficient quantities of clean energy to make the above comments suggestion work.