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.
A fuel cell consists of two electrodes sandwiched around
an electrolyte. Oxygen passes over one electrode and hydrogen over the
other, generating electricity, water and heat.
Hydrogen fuel is fed into the "anode" of the fuel cell.
Oxygen (or air) enters the fuel cell through the cathode. Encouraged by
a catalyst, the hydrogen atom splits into a proton and an electron,
which take different paths to the cathode. The proton passes through
the electrolyte. The electrons create a separate current that can be
utilized before they return to the cathode, to be reunited with the
hydrogen and oxygen in a molecule of water.
A fuel cell system which includes a "fuel reformer" can
utilize the hydrogen from any hydrocarbon fuel - from natural gas to
methanol, and even gasoline. Since the fuel cell relies on chemistry
and not combustion, emissions from this type of a system would still be
much smaller than emissions from the cleanest fuel combustion
processes.
Did You Know?
The voltage from a single cell is
about 0.7 volts, just about enough for a light bulb.
When the cells are stacked in a series,
the operating voltage increases to 0.7 volts multiplied by the number
of cells stacked.
Put together a
fuel cell! Play the Fuel
Cell Components
Game on the NAIT
Fuel Cell Applied
Research
Project
website.
