Environmental Engineering Reference
In-Depth Information
8
Fuel Cells
I believe that water will one day be employed as a fuel, that hydrogen and oxygen
which constitute it, used singly or together, will furnish an inexhaustible source of heat
and light.
—Jules Verne (
Mysterious Island
, 1874)
I believe fuel cell vehicles will finally end the hundred-year reign of the internal com-
bustion engine as the dominant source of power for personal transportation. It's going
to be a winning situation all the way around—consumers will get an efficient power
source, communities will get zero emissions, and automakers will get another major
business opportunity—a growth opportunity.
—William C. Ford, Jr., Ford Chairman, International Auto Show, 2000
INTRODUCTION TO HYDROGEN FUEL CELLS
*
Containing only one electron and one proton, hydrogen, chemical symbol H, is the
simplest element on earth. Hydrogen as is a diatomic molecule—each molecule has
two atoms of hydrogen (which is why pure hydrogen is commonly expressed as H
2
).
Although abundant on Earth as an element, hydrogen combines readily with other
elements and is almost always found as part of another substance, such as water
hydrocarbons or alcohols. Hydrogen is also found in biomass, which includes all
plants and animals.
•
Hydrogen is an energy carrier, not an energy source. Hydrogen can store
and deliver usable energy, but it does not typically exist by itself in nature;
it must be produced from compounds that contain it. Its production is not
inexpensive.
•
Hydrogen can be produced using diverse, domestic resources including
nuclear energy, natural gas and coal, and biomass and other renewables,
including solar, wind, hydroelectric, and geothermal energy. This diversity
of domestic energy sources makes hydrogen a promising energy carrier and
important to our nation's energy security. It is expected and desirable for
hydrogen to be produced using a variety of resources and process technolo-
gies (or pathways).
*
Adapted from EERE,
Hydrogen Production
, Office of Energy Efficiency & Renewable Energy, U.S.
Department of Energy, Washington, DC, 2014 (
http://www1.eere.energy.gov/hydrogenandfuelcells/
production/basics.html);
Spellman, F.R. and Bieber, R.,
The Science of Renewable Energy
, CRC Press,
Boca Raton, FL, 2011.
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