Serious interest in the fuel cell as a practical generator did not begin until the 1960's, when the U.S. space program chose fuel cells over riskier nuclear power and more expensive solar energy. Fuel cells furnished power for the Gemini and Apollo spacecraft, and still provide electricity and water for the space shuttle. In principle, a fuel cell operates like a battery. Unlike a battery, a fuel cell does not run down or require recharging. It will produce energy in the form of electricity and heat as long as fuel is supplied.
Fuel cells can promote energy diversity and a transition to renewable energy sources.
Fuel cells can also utilize fuel containing hydrogen, including methanol, ethanol, natural gas, and even gasoline or diesel fuel. Energy also could be supplied by biomass, wind, solar power or other renewable sources. Fuel cells today are running on many different fuels, even gas from landfills and wastewater treatment plants. Fuel cells can power everything from cell phones, laptop computers and vehicles as well as larger systems for utility power plants and cogeneration facilities. In the future, flywheels may be used to store energy for discharge over longer periods.