It is an odd twist of chemistry that there is fuel embedded in the most common substance on earth: water.
Hydrogen — the H of H2O fame — turns out to be something of an all-purpose element, a Swiss Army knife for energy. It can be produced without greenhouse gases. It is highly flammable, so it can be used as a combustion fuel. It can be fed into a fuel cell to produce electricity directly, without combustion, through an electrochemical process.
It can be stored and distributed as a gas or a liquid. It can be combined with CO2 (and/or nitrogen and other gases) to create other useful fuels like methane or ammonia. It can be used as a chemical input in a range of industrial processes, helping to make fertilizers, plastics, or pharmaceuticals.
It is quite handy.
