It's the put the pollution somewhere else policy so that cities are more liveable. It was hurting China's reputation and too many rich Chinese were going overseas and siphoning away the economy (and still are).

I'd like to prefix this all by pointing out that coal is absolutely terrible to use in several ways.

However: most thermal plants get about 45% efficiency, based on using very high steam temperatures. We all know that the theoretical max efficiency for a thermal process is limited by the Carnot cycle, which explicitly depends on the difference in temperature between the working fluid and the surroundings.

I'd also like to point out an important point: carbon plants are not constricted by the need to keep the engine lightweight, we can capture most fly ash and other process exhaust.

I again, do not care to bring such an arcane tech back online, it's terrible to mine, process and use. Just remember there's a bit more to all of this that engineers have indeed thought of.

E: https://www.sciencedirect.com/science/article/abs/pii/S0196890415007657

Yup, and that's ignoring the loss in transforming and transporting the energy across the grid, and in the chemistry of the battery itself through charges and discharges. Energy density of batteries is also a fraction of that of petrol, so every EV is also carrying around a lot of extra weight.

It turns out that the lithium is very recyclable. The process of disassembly is what's tricky, but one of Tesla's pre-musk founders is working specifically on this problem.

We can already do it. Mining is (for now) cheaper. Something legislation, applied carefully, can resolve.