Page 311 - Biofuels Refining and Performance
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290 Chapter Nine
industrial facilities; and distributed power generation systems for util-
ities. Although some demonstration and commercial stationary fuel cell
power plants in sizes from a few kilowatts to 11 MW are in operation,
widespread commercialization can be expected only if their installation
cost drops down from the present cost of $4000/kW to about $400–700/kW
(or about $1000/kW for some premium applications).
The recent surge of interest in fuel cell technology is because of its
potential use in transportation applications, including personal vehicles.
This development is being sponsored by various governments in North
America, Europe, and Japan, as well as by major automobile manufac-
turers worldwide, who have invested several billion dollars with the
goal of producing a high-efficiency and low-emission fuel cell power
plant at a cost that is competitive with the existing internal combustion
engines. With hydrogen as the onboard fuel, such vehicles would be
zero-emission vehicles. With fuels other than hydrogen, an appropriate
fuel processor to convert the fuel to hydrogen will be needed. Fuel cell-
powered vehicles offer the advantages of electric drive and low mainte-
nance, because of the few critical moving parts. The major activity in
transportation fuel cell development has focused on the polymer elec-
trolyte fuel cell (PEFC), and many of the technical objectives related to
the fuel cell stack have been met or are close to being met. The current
development efforts are focused on decreasing cost and resolving issues
related to fuel supply and system integration.
Besides exotic areas of applications such as space vehicles or sub-
marines, another very promising area of application for fuel cells is
portable power systems. Portable power systems are small, lightweight
systems that power portable devices (e.g., computers, laptops, cellular
phones, and entertainment electronic devices), camping and recreational
vehicles, military applications in the field, and so forth. These devices
need power in the range of a few watts to a few hundred watts. Fuel cell
systems based on DMFC or PEMFC technology are well suited for many
of these applications. The convenience of transporting and storing liquid
methanol makes DMFC systems very attractive for this application. A
small container of methanol or a cylinder of compressed hydrogen can
be used as a fuel supply. When the fuel is depleted, a new fuel container
may be installed in its place after removing the old one.
In recent years, there has been a lot of interest in electric power gen-
eration using renewable energy sources such as wind energy, solar
energy, and tidal energy. A major problem with these energy sources is
that all are intermittent in nature. Combining the renewable energy-
based power generation system with a fuel cell system would solve this
problem to a great extent. A hybrid wind/solar energy–fuel cell system
can use wind/solar power for generating hydrogen using the electroly-
sis of water, and store it in cylinders at high pressure. This hydrogen can