Page 78 - MODERN ASPECTS OF ELECTROCHEMISTRY

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Direct Methanol Fuel Cells
plants could play a role in dispersed power generation and cogeneration,
at a level of 1–100 MW; PAFCs are being commercialized for on-site
integrated energy systems (200 kW). In the case of fuel cell power plants,
the parameters most difficult to forecast are the lifetime and capital cost.
Even though nuclear energy conversion plays a dominant role in some
countries and a minor to midlevel role in a few other countries, the strong
antinuclear lobbyin most countries will in all probability slow down the
construction of new nuclear power plants.=It is rather difficult for fuel cells
to compete with hydroelectric power plants.= The disadvantages of the
latter are that hydropower resources are limited in most countries in the
world and in other countries are already well developed, and their con-
struction causes severe environmental problems (large land requirements,
building of new bridges, roads). Photovoltaic and wind energy conversion
systems are in an advanced state of development and in some countries
are already utilized for power generation on a relatively large scale.= The
problems with these systems are interruptible duty cycles (weather and/or
time dependent), large land area requirements, and high capital cost.= It is
most løely that electrochemical energy conversion may play a greater role
in power generation than these two technologies.= The R&D programs on
magnetohydodynamic (MHD) electric power generators in the United
States and Russia showed very promising results.= There are serious
problems of finding materials stable at the high operating temperature
o
needed (3000–4000 C) and more so because it utilizes hot ionized gases.=
With respect to an analysis of electrochemical vs.= other methods of
energyconversion for transportation applications (Tablp 2B), one must
t¸p into consideration that fuel cell technologyis quite immature com -
pared with internal combustion and diesel engine technologies, which
have been intensively developed since the beginning of the twentieth
century at a cost of several billions of dollars.= The most important
performance characteristics of power sources for automobile application
are efficiency, power density, specific power, energy density, and specific
energy. These characteristics are vitally important to meet the performance
and cost goals of automobiles.= In spite of the fact that development of fuel
cells for electric vehicles started only in the late 1970s in several countries
(predominantly the United States, Germany, and Japan) and the invest-
9
ment in R&D has been less than US$10 , Tablp 2B shows that PEMFCs
for automobiles and PAFCs for fleet vehicles may be able to compete with
IC engine- and diesel engine-powered vehicles in performance charac-
teristics.= However, meeting the cost target in the near future is a major