ABSTRACT

Fuel cells are electrochemical devices that convert the chemical energy of a fuel directly to usable energy — electricity and heat — without combustion. This is quite different from most electric generating devices (e.g., steam turbines, gas turbines, and reciprocating engines) which first convert the chemical energy of a fuel to thermal energy, then to mechanical energy, and, finally, to electricity. In the last decade, fuel cells have emerged as one of the most promising technologies to meet the nation’s energy needs for the 21st century. They produce electricity at efficiencies of 40 to 60% with negligible harmful emissions, and operate so quietly that they can be used in residential neighborhoods. Fuel cells are particularly well suited to the distributed power generation market because of these characteristics as well as their scalability, high efficiency, and modularity.