Solar and wind are both cheaper than fossil fuels when you account for oil/gas being heavily subsidized by tax incentives as well. Solar is now the cheapest energy in history. The issue has always been storage but that has been pretty much figured out as well.
There is an environmental cost for everything -- at this point it's clear that the #1 priority is to get net CO2 emissions close to zero by the middle of the century so if there are other externalities from mining, manufacturing, etc we'll just have to deal with that.
We're never going to see the average person fueling their car with hydrogen (who would want to do that when home charging is so easy), but hydrogen produced by nuclear to power heavy machinery has potential. The main issue with nuclear continues to be the cost relative to other green energy sources. I know much of that cost is caused by people being irrationally scared of nuclear, but that's a real problem that has to be solved to scale it.