British hydrogen car unveiled - How does a fuel cell car work?

Fuel cells are catalytic devices, which convert the energy stored in a fuel (in this case hydrogen) directly into electrical energy. The electricity is used to power one or more electric motors, which in turn drive the car.

Until recently, production costs have been astronomically high, however prices are coming down. The Riversimple's lightweight construction allows it to run off a tiny fuel cell, which brings down the price further and keeps the system compact.