Comment by adgjlsfhk1

That's not really a problem. A spin up over a couple hours matches nicely with the slow sunset over a continent. The sun takes ~4 hours to go from a bit above the horizon in the east coast to a bit below the horizon on the west coast (solar panels make some power in twilight).

Wind also helps since wind makes more power at night, as does demand which is dramatically lower at night.

For coal, Great. Making coal economical is excellent. We should have banned it worldwide 20 years ago.