Hydrogen fuel is a stupid idea
You have to be completely mad to think hydrogen is the future of vehicle power. In fact the whole solution is just plain bad engineering.
The only way we currently know to generate large amounts of *clean* hydrogen is via electrolysing water, splitting into it's constituent 2H2 + 02. This process is ~30% efficient.
Then, assuming you aren't generating it at the pump, you need to either compress it or refrigerate the hydrogen to transport it - both of which require energy - not least to power the vehicle infrastructure itself.
Then, either a highly pressurised or very cold highly flammable liquid is pumped and stored in the local petrol - err hydrogen station - wonderful terrorist targets - they'll burn very nicely - think of the Hindenburg.
After that, Grandma has to be comfortable handling this highly flammable liquid and storing it in her car - hoping it doesn't all evaporate or explode in hot weather or fire.
On board the car we pump (yet more cost, complexity & failure points) the hydrogen and combine it over a fuel cell (that is effectively a battery), which itself is less than 50% efficient (and the efficiency drops proportionally to the power draw), to create electricity that is then sent to a bulk standard electric motor.
Thus excluding distribution: 100% -> 30% -> 50% -> Electric Motor
The alternative is instead of converting the electricity to Hydrogen - just store it in a battery (which can be up to 80% efficient) on the car and send it straight to the electric motor. No production or storage of highly flammable cold/pressurised gases, no mechanics for pumping fuel, no expensive crash-proof hydrogen tanks, no tricky pressurised fuel seals for the fuel caps (Challenger anyone?)
Thus: 100% -> 80% -> Electric motor
Aside from the safety, complexity, reliability and performance (see http://www.teslamotors.com) issues, what happens when solar cells become so cheap we can integrate them onto a vehicle shell - where can you store that energy? Or how about vibration dampers that pick up the vibrations in passing traffic and trickle charge batteries with it?
Hydrogen fuel is just a plain stupid idea. Period.
In fact the only people that justifiably think hydrogen is the future of vehicle power are CEOs of the large oil companies, because if we all start charging our cars up at home or work, they won't have anything to sell us, and even less reason to visit their little shops to buy a 2 day old sandwich.
Unless they're getting into the property business, they need us to buy hydrogen or their dead - and they know it.