The volume of nuclear waste is very much less than the waste from fossil fuel generation of electricity. Most of that goes up the stack, forming greenhouse gasses. And in the case of coal in particular, releases a bunch of radioactivity.

With the notable exception of Chernobol, the only real nuclear-waste messes and serious nasties are related to weapons production.

Ethenol has a long way to go before it's cost effective. You just have to grow too much corn for the energy recovered.

Bio diesel is more interesting. I believe part of the future energy mix will involve growing crops specialized for their oil production. Should work as bio diesel. And for air transport - gas turbine engines will work well on almost any liquid fuel.

/Neal