What is hydrogen?
Hydrogen or H2 is an invisible, odourless and non-toxic gas that is lighter than air and easily forms compounds, which means it easily reacts with other molecules. The most commonly known compound is with oxygen: H2O, which is water. H2 is a powerful energy carrier that can be used in fuel cells to generate electricity to power vehicles, or heating systems. Driving on hydrogen is clean: no harmful substances such as pollutants and greenhouse gases are emitted from the vehicle exhaust.