"The hydrogen economy is a proposed system of delivering energy using hydrogen. The term hydrogen economy was coined by John Bockris during a talk he gave in 1970 at General Motors (GM) Technical Center.[1] Hydrogen advocates promote hydrogen as a potential fuel for motive power[2] (including cars and boats), the energy needs of buildings and portable electronics. Free hydrogen does not occur naturally in quantity, but can be generated by steam reformation of hydrocarbons, water electrolysis or by other methods. Hydrogen is thus an energy carrier (like a battery), not a primary energy source (like coal). The feasibility of a hydrogen economy depends on issues of electrolysis, energy sourcing, including fossil fuel use, climate change, and sustainable energy generation."

A fuel cell is an electrochemical device that combines hydrogen and oxygen to produce electricity, with water and heat as its by-product.