Hydrogen cars face technological hurdles: experts

http://news.yahoo.com/s/nm/20070321/sc_nm/hydrogen_cars_dc;_ylt=AtnpBdL7Vj.brmOLuD4IDJYDW7oF
BMW, Toyota, Honda, GM, DaimlerChrysler and Volkswagen have hydrogen-powered vehicles on display at the conference, but all have similar technological challenges, including costs that range up to a million dollars a piece and limited range on a hydrogen fill-up.

A hydrogen car can travel 45 to 50 miles on a gallon, but a normal-sized fuel tank will only provide a range of 125 to 150 miles, experts said.

That's because hydrogen is put in a car as a liquid at very low temperatures, but reverts to being a gas as it warms. It dissipates into the air even if the vehicle is not being used.