Fuel cells are power generation systems that utilize a fuel, usually hydrogen. Hydrogen fuel cells combine hydrogen with oxygen generating steam as a byproduct or exhaust. They are not the answer to all our energy needs but are a major component in the system of sustainable power generation. More importantly they allow energy production to be decentralized and located on site.

Potentially the steam produced by the fuel cell can also be used to generate electricity as well as be used for hot water and heating.