All things being equal, I believe improvements in coal technology is more practical and more plausible than major advancements in renewable technologies. For example, how many billion of dollars have been sunk into hydrogen fuel cells, and still no hydrogen fuel cells, yet the coal industry has already figured out how to scrub their emmissions so well that the days of the black death cloud of london has been a fact for the history books because it doesnt happen anymore.
There are usable hydrogen cells.BC Transit had a bunch of busses running on them. High maintenance poor performance. Went back to diesel.