Combining with oxygen, the reaction pumps out electricity, heat and pure water. Most fuel cells use fossil fuels, breaking hydrogen from carbon. So fuel cells release some climate-altering greenhouse gases, but less than if the fuel is burned. A company called Energy Conversion Devices is working on an even safer solid-form hydrogen. Fuel cells can be scaled from postage-stamp size to utility power plant.
Several companies plan to market home systems around the size of a major appliance.
Today a couple of hundred 200-kilowatt fuel cells are part of the power supply at institutional sites ranging from a New York City police station to Vandenberg Air Force Base. Tomorrow they will be everywhere. Mass production economies are expected to dramatically drop prices in a few years. GE plans to market business-scale systems by 2002. Auto industry developments are also moving at a frenzied pace.