A Fuel Cell is an electrochemical device
similar to a battery, but differing from the latter in that it is
designed for continuous replenishment of the reactants consumed;
i.e. it produces electricity from an external fuel supply as opposed
to the limited internal energy storage capacity of a battery.
Typical reactants are hydrogen on the anode side and oxygen on the
cathode side. In contrast, conventional batteries consume solid
reactants and, once these reactants are depleted, must be discarded
Typically in fuel cells, reactants flow in and reaction products
flow out, and continuous long-term operation is feasible virtually
as long as these flows are maintained. The Fuel
Cell 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
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 utilised 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 utilise 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.
In fact fuel cells running on
hydrogen derived from a renewable source will emit nothing but water
The production of fuel cells is
more than just a dream, research in to fuel cells is continuing by
around the world with Australia's CSIRO being a major player as
vehicles can eventually offer a practical solution to the problem of
automotive pollution while reducing the world's dependence on oil.
George Bush has recently committed millions of US tax payer dollars to
research development of both Hydrogen and Fuel Cell manufacture.