Several types of fuel cells have been developed. Below are some of the more
common:
Polymer electrolyte membrane fuel cells. If you have heard about fuel cell use
in vehicles, you are probably familiar with polymer electrolyte membrane fuel
cells. These cells, also known as PEM fuel cells, probably hold the most promise
to date for use in powering personal vehicles. These fuel cells actually use a
polymer membrane in place of the electrolyte. They are able to operate at fairly
low temperatures. These fuel cells are able to alter their output to meet
changing demands for power. In addition to their potential use in vehicles, PEM
fuel cells also hold potential for power generation while stationary.
Regenerative fuel cells. This is a special class of fuel cells, and like other
fuel cells, regenerative fuel cells create electricity from hydrogen and oxygen.
But they differ from other fuel cells in one important way: the process can be
reversed and the fuel cell powered with electricity to produce hydrogen and
oxygen. Why is this important? Some day, the technology of these fuel cells
could provide storage of excess energy that is produced by varying sources of
renewable energy, be it wind or solar or some other source. During times of
lower power production, the energy can then be released.
Direct-methanol fuel cell. These fuel cells are similar to the more common PEM
cell, using a polymer membrane as the electrolyte. But unlike the PEM cell,
these fuel cells use methanol directly on the anode, eliminating any need for a
fuel reformer. These fuel cells are beginning to garner more attention.
Phosphoric Acid Fuel Cells. Used most often in modules of 400 kW or more, these
fuel cells are often tapped for use in generating power for places like hotels,
hospitals, stores and commercial buildings, and often contain systems that allow
for the use of waste heat. Phosphoric acid fuel cells use a phosphoric acid
electrolyte held inside a porous matrix, operating at around 200 degrees C.
Phosphoric acid is sometimes immobilized in polymer membranes, allowing for use
in a number of stationary power application situations.
Morocco, Rabat
Iraq, Baghdad
Austria, Vienna
Lexington, Kentucky
Lafayette, Louisiana
Slovakia, Bratislava
Sierra Leone, Freetown
Tajikistan, Dushanbe
Bridgeport Connecticut USA
City of Lake Macquarie, Australia