Electrolysis is a fairly inefficient way to produce hydrogen. If you've got enough energy to do electrolysis, then you've got enough energy to run a motor. The

Electrolysis is a fairly inefficient way to produce hydrogen. If you've got enough energy to do electrolysis, then you've got enough energy to run a motor. The only technical reason you'd want to use hydrogen is that you can do combustion and long-term fuel storage. It would be valuable if you were using something like sunlight to produce hydrogen, since sunlight can't really run a car.