dollars
why don't we have any nuclear power plants? they're expensive. now. they were cheapest energy around by a long shot 40 years ago. why are they expensive now? labor. you'd think mining coal would be more labor. but that's cheap labor. nuclear power plants need lots of professional labor. which is very expensive. first, the things are not idiot proof. so you need highly trained engineers staffing them. second and more importantly, lawyers are involved. there are so many laws and regulations and shit to wade through. it's crazy. and expensive. in the end, it's cheaper to burn coal.