I don't understand why people are confused about using hydrogen to run your vehicle. It's obviously very explosive, which is why we switched to helium balloons. It's also obvious that trying to get your alternator to perform the electrolysis isn't the proper way, but the electrolysis would be done at home. A separate system, likely ran off of solar panels or a heat engine, would produce the hydrogen. At the moment electric cars aren't efficient enough. Batteries don't store enough energy, they're too heavy and solar panels don't absorb enough energy to run a car the way gasoline powered engines would. One day once battery technology and solar technology has improved, than they'll be the better cars. As far our engines not being able to run of hydrogen, kenetic energy is kenetic energy. The pistons can't tell the difference so long as you properly regulate the hydrogen, there's no issue.