A fuel cell turns hydrogen, the fuel, into electricity using air and other catalysts. The fuel cell harnesses chemical energy trapped in hydrogen gas and converts it into the kinetic energy we know as electricity, without fossil fuels, combustion, or polluting emissions. As a remarkably efficient, incredibly clean source of renewable energy, fuel cells can take the place of both batteries and engines to power vehicles, laptops, and residential power grids.
The technology of fuel cells has been well researched and developed, although for economic and political reasons, they have not been widely implemented. Such a clean power source, as part of a widespread hydrogen economy, guarantees less dependence on the dwindling supplies of fossil fuels, creates less greenhouse gases that contribute to global climate change, and does not explode or malfunction as frequently as engine-driven electricity.
Chemically, a fuel cell takes in hydrogen and air, creates electricity, and produces byproducts of water and heat. The outside layers of a fuel cell are the anode plate, with a positive charge, and the cathode plate, with a negative charge. Together with the center electrolyte plate, they are catalytic environments that encourage certain electrochemical functions.
The anode separates hydrogen into protons and electrons. The electrons flow along a path, producing electrical current for a circuit, while protons move through the electrolyte to the cathode. The cathode combines oxygen with protons, as well as collecting some of the electrons in the circuit, to recombine them into water. The cathode allows water, and extra heat, to be used as additional sources of energy.
An independent hydrogen supply, as from a tank at a station, doesn't need to be the sole source of fuel in a fuel cell. In fact, one can run on rotting organic material, like vegetation, because that gives off hydrogen, too. Or hydrogen might be separated from oxygen out of water, through electrolysis, by solar or wind power. If water is used as a source of hydrogen, the fuel cell is practically immortal, as it continues the cycle from water to hydrogen to water.
Additionally, a fuel cell is flexible because it can be small and portable or larger and permanent. The cost to convert to a fuel cell-driven power grid may initially be high, but over time it will significantly reduce the costs of maintenance, repair, and fuel compared to conventional electricity generators. If one can use the resulting heat, say, to warm a house during winter, the fuel cell becomes even more cost effective.