The problem of what to do with the "spent" nuclear fuel? The answer, it is not "spent" at all, as some 97% of the energy that was originally present in the fuel rods is still available, but that reprocessing the fuel rods concentrates plutonium, of which the anti-nuke types have a superstitious dread, as it can be made into DIRTY BOMBS, and WE'RE ALL GONNA DIE!
The plutonium itself makes fuel for the atomic reactors, and eventually decays into a safe form, albiet more slowly than the radioactive isotope of uranium. The thing is, it is all heat, and heat is what forms the steam that drives the power generators.
For the amount of energy generated, the cost is very low, and the nuclear-driven power plants COULD generate electricity even more cheaply than hydro plants, or wind-driven plants, or even photo-voltaic plants. The power thus generated is used to electrolyze water, that is, break the hydrogen out of the water molecule, where it is collected and used to drive the ultimate low-emissions vehicle, the fuel cell-electric.
Hydrogen is not a primary power source, it is only an intermediary between the nuclear-generated electricity and propulsion of a free-ranging road vehicle. The oxygen generated by the electrolysis is taken up on the recombination with the hydrogen.