[matthewdgreen]

This is one of the reasons hydrogen cars are unlikely to achieve any widespread deployment. But the new proposal is hydrogen-carrying trucks, which is better (larger tanks and bigger scale means more and better maintenance than a typical passenger vehicle can justify) but also, it means extremely high pressure hydrogen tanks on the road with your traffic.

(Of course, it may not happen. Trucking hydrogen around is pretty inefficient and stupid: hopefully it will prove cheaper to pipe electrons around and generate hydrogen on site for whatever industrial process requires it.)