[yourapostasy]

> ...why do we still use steam?

It hits the sweet spot on fiscal, engineering, safety, and science fronts. Energy extraction is very challenging, we're likely hundreds of years away from aneutronic fusion, for example. The research area you are asking about is direct energy conversion, of which aneutronic fusion is one small branch (though within it, there are many scientific and engineering branches to explore).

[perl4ever]

I think I may have said this before, but a statement like "we're likely hundreds of years away from aneutronic fusion" seems to me necessarily meaningless.

We're only a bit over a hundred years from developing quantum mechanics and relativity, how can we possibly say anything about hundreds of years from now?

If something is well enough understood to accurately predict the timeline, we could do it much sooner.

If we have no idea how to do something, then "hundreds of years" means nothing, except maybe "not proven impossible yet".