Hydrogen Gas
The Morgan Lifecar
Hydrogen is a volatile gas at room temperature, but when chilled to -253C and compressed, it makes the perfect fuel. Hydrogens' greatest feature, as a fuel, is that it causes no pollution.
A hydrogen fuel cell works by combing hydrogen gas with atmospheric oxygen. The resulting chemical reaction generates electric power, and the only by-product it produces is clean water. At a time when there is real concern about global warming due to carbon emissions, this makes hydrogen fuel a desirable technology and perhaps the most feasible alternative to petrol and gasoline.