See Also: Generation - Distributed
Electric Cell in which the chemical Energy from the oxidation (see Oxidation and Reduction) of a Gas (see States Of Matter) fuel is converted directly to electrical energy (Direct Current (DC) ) in a continuous process. Since no combustion (see Internal-Combustion Engine) takes place a fuel cell is virtually pollution free and more efficient than
thermal generation (see Generator). A fuel cell is very quiet and compact, so they can be sited at or near
customer loads, reducing pressure on the transmission and Distribution system.
In the Hydrogen and Oxygen fuel cell, hydrogen and oxygen gas are bubbled into separate compartments
connected by a porous disk through which an Electrolyte, such as aqueous Potassium hydroxide (KOH), can pass. Inert graphite Electrodes, mixed with a catalyst such as Platinum, are dipped into each compartment. When the two Electrodes are electrically connected, an Oxidation and Reduction reaction takes place in the cell: hydrogen gas is oxidized to form Water at the Anode; Electrons are liberated in this process and flow through the external circuit to the Cathode, where the electrons combine with the oxygen gas and reduce it.
Historically, fuel cells have only been used to generate Electricity in spacecraft. By the spring of 1996 Jersey Central Power & Light had a
200-KW fuel cell providing baseload Power to a customer with critical laboratory and Computer loads.
The most promising, as of August, 1996, fuel cell technologies are discussed
below:
Phosphoric Acid Fuel Cell - (PAFC)
Are commercially available at a 200-kw size and have proven highly reliable in
over 70 field applications. Several such units recently passed one year of
continuous operation without a forced shutdown (see Forced Outage). Current prices run about $3,000/kw (twice what their market value would
support), but higher-volume production could trim prices to $1,500/kw in three to
five years.
Molten Carbonate Fuel Cell - (MCFC)
Run at higher thermal efficiency and carry a smaller installed footprint for a given capacity. A 2-MW demonstration plant recently began operation in
California. The next-generation commercial plant (3 MW, year 2000) could fit
on the area covered by two tennis courts.
Solid Electrolyte or Solid Oxide Fuel Cell - (SOFC)
Still under development. By 2002, cells in the range of 15 kw to 3 MW could
serve as small cogenerators in commercial buildings, multi-residential
buildings, and mega- Watt class, all-electric distributed power systems with efficiencies in the 60- to
65-percent range.
A 2 mega-watt fuel-cell plant, the world’s largest, went on line April 26, 1996 in Santa Clara, California. For an
update on how this plant is doing go to the www.ercc.com page on the Internet (see Internet - Overview).