Hydrogen fuel cells are poised to become the technology of choice to address the pollution, global warming, and energy dependence problems inherent in our current reliance on fossil fuels. First invented by a chemist in the mid-1800s, fuel cells work somewhat like a battery, in that they produce an electric current that can drive a motor. However, unlike a battery, they do not store energy but depend on a steady supply of fuel, the way a combustion engine does. Inside the fuel cell, a catalyst divides the hydrogen atoms into protons and free electrons. These electrons produce the electric current, while the protons combine with the oxygen to produce water and heat the only by-products of the reaction.
Fuel cells have the added advantages of quiet operation and no moving parts.
Until recently, fuel cells were both bulky and expensive, which made them very impractical for most power needs, particularly transportation. The one exception has been space travel, for which the high cost was not a deterrent. Fuel cells fit the needs of NASA for an energy source that was reliable, efficient, and clean. First used in space to supply electrical power to the Apollo spacecraft, fuel cells today provide all of the electrical power for the space shuttle. The great attraction of fuel cells for use on earth is that they seem miraculously suited to address most of the air pollution and energy problems caused by combustion of fossil fuels.