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					                     Fuel Cell Technology




ABSTRACT
You may have heard a lot recently about fuel cells. According to many news reports,
we may soon be using the new energy-saving technology to generate electrical
power for our homes and cars. The technology is extremely interesting to people in
all walks of life because it offers a means of making power more efficiently and with
less pollution. A fuel cell is an electrochemical energy conversion device. A fuel cell
converts the chemicals hydrogen and oxygen into water, and in the process it
produces electricity. In addition to clean, quiet operation, fuel cells offer highly
reliable, high-quality electricity.
In this paper, we'll take a look at each of the existing or emerging fuel-cell
technologies. We'll detail how one of the most promising technologies works, and
we'll discuss the potential applications of fuel cells.


What is a fuel cell?
 A fuel cell is an electrochemical device that combines hydrogen and oxygen to
 produce electricity, with water and heat as its by-product. As long as fuel is
 supplied, the fuel cell will continue to generate power. Since the conversion of
 the fuel to energy takes place via an electrochemical process, not combustion,
 the process is clean, quiet and highly efficient ± two to three times more
 efficient than fuel burning.
 No other energy generation technology offers the combination of benefits that
 fuel cells do. In addition to low or zero emissions, benefits include high
 efficiency and reliability, multi-fuel capability, siting flexibility, durability,
 scalability and ease of maintenance. Fuel cells operate silently, so they reduce
 noise pollution as well as air pollution and the waste heat from a fuel cell can be
 used to provide hot water or space heating for a home or office.



 How does a Fuel Cell work?
     It operates similarly to a battery, but it does not run down nor does it
      require recharging
     As long as fuel is supplied, a Fuel Cell will produce both energy and heat
     A Fuel Cell consists of two catalyst coated electrodes surrounding an
      electrolyte
     One electrode is an anode and the other is a cathode
     The process begins when Hydrogen molecules enter the anode
     The catalyst coating separates hydrogen¶s negatively charged electrons
      from the positively charged protons
     The electrolyte allows the protons to pass through to the cathode, but not
      the electrons
     Instead the electrons are directed through an external circuit which creates
      electrical current


      In principle, a fuel cell operates like a battery. Unlike a battery, a fuel cell
does not run down or require recharging. It will produce energy in the form of
electricity and heat as long as fuel is supplied.
A fuel cell consists of two electrodes sandwiched around an electrolyte. Oxygen
passes over one electrode and hydrogen over the other, generating electricity,
water and heat.




Hydrogen fuel is fed into the "anode" of the fuel cell. Oxygen (or air) enters the
fuel cell through the cathode. Encouraged by a catalyst, the hydrogen atom
splits into a proton and an electron, which take different paths to the cathode.
The proton passes through the electrolyte. The electrons create a separate
current that can be utilized before they return to the cathode, to be reunited
with the hydrogen and oxygen in a molecule of water.
A fuel cell system which includes a "fuel reformer" can utilize the hydrogen from
any hydrocarbon fuel - from natural gas to methanol, and even gasoline. Since
the fuel cell relies on chemistry and not combustion, emissions from this type of
a system would still be much smaller than emissions from the cleanest fuel
combustion processes.
Types of Fuel Cells
    Fuel cells are classified primarily by the kind of electrolyte they employ. This
    classification determines the kind of chemical reactions that take place in the
    cell, the kind of catalysts required, the temperature range in which the cell
    operates, the fuel required, and other factors. These characteristics, in turn,
    affect the applications for which these cells are most suitable. There are several
    types of fuel cells currently under development, each with its own advantages,
    limitations, and potential applications. Learn more about:

y    Polymer Electrolyte Membrane (PEM) Fuel Cells
y    Direct Methanol Fuel Cells
y    Alkaline Fuel Cells
y    Phosphoric Acid Fuel Cells
y    Molten Carbonate Fuel Cells
y    Solid Oxide Fuel Cells
y    Regenerative Fuel Cells
y    Comparison of Fuel Cell Technologies




    Polymer Electrolyte Membrane (PEM) Fuel Cells




    Polymer electrolyte membrane (PEM) fuel cells²also called proton exchange
    membrane fuel cells²deliver high-power density and offer the advantages of low
    weight and volume, compared with other fuel cells. PEM fuel cells use a solid
    polymer as an electrolyte and porous carbon electrodes containing a platinum
    catalyst. They need only hydrogen, oxygen from the air, and water to operate
    and do not require corrosive fluids like some fuel cells. They are typically fueled
    with pure hydrogen supplied from storage tanks or on-board reformers.
Polymer electrolyte membrane fuel cells operate at relatively low temperatures,
around 80°C (176°F). Low-temperature operation allows them to start quickly
(less warm-up time) and results in less wear on system components, resulting in
better durability. However, it requires that a noble-metal catalyst (typically
platinum) be used to separate the hydrogen's electrons and protons, adding to
system cost. The platinum catalyst is also extremely sensitive to CO poisoning,
making it necessary to employ an additional reactor to reduce CO in the fuel gas
if the hydrogen is derived from an alcohol or hydrocarbon fuel. This also adds
cost. Developers are currently exploring platinum/ruthenium catalysts that are
more resistant to CO.
PEM fuel cells are used primarily for transportation applications and some
stationary applications. Due to their fast startup time, low sensitivity to
orientation, and favorable power-to-weight ratio, PEM fuel cells are particularly
suitable for use in passenger vehicles, such as cars and buses.
A significant barrier to using these fuel cells in vehicles is hydrogen storage.
Most fuel cell vehicles (FCVs) powered by pure hydrogen must store the
hydrogen on-board as a compressed gas in pressurized tanks. Due to the low-
energy density of hydrogen, it is difficult to store enough hydrogen on-board to
allow vehicles to travel the same distance as gasoline-powered vehicles before
refueling, typically 300±400 miles. Higher-density liquid fuels, such as methanol,
ethanol, natural gas, liquefied petroleum gas, and gasoline, can be used for fuel,
but the vehicles must have an on-board fuel processor to reform the methanol
to hydrogen. This requirement increases costs and maintenance. The reformer
also releases carbon dioxide (a greenhouse gas), though less than that emitted
from current gasoline-powered engines.

Direct Methanol Fuel Cells

Most fuel cells are powered by hydrogen, which can be fed to the fuel cell
system directly or can be generated within the fuel cell system by reforming
hydrogen-rich fuels such as methanol, ethanol, and hydrocarbon fuels. Direct
methanol fuel cells (DMFCs), however, are powered by pure methanol, which is
mixed with steam and fed directly to the fuel cell anode.
Direct methanol fuel cells do not have many of the fuel storage problems typical
of some fuel cells because methanol has a higher energy density than
hydrogen²though less than gasoline or diesel fuel. Methanol is also easier to
transport and supply to the public using our current infrastructure because it is a
liquid, like gasoline.
Direct methanol fuel cell technology is relatively new compared with that of fuel
cells powered by pure hydrogen, and DMFC research and development is roughly
3±4 years behind that for other fuel cell types.

Alkaline Fuel Cells
 Alkaline fuel cells (AFCs) were one of the first fuel cell technologies developed,
 and they were the first type widely used in the U.S. space program to produce
 electrical energy and water on-board spacecrafts. These fuel cells use a solution
 of potassium hydroxide in water as the electrolyte and can use a variety of non-
 precious metals as a catalyst at the anode and cathode. High-temperature AFCs
 operate at temperatures between 100°C and 250°C (212°F and 482°F).
 However, newer AFC designs operate at lower temperatures of roughly 23°C to
 70°C (74°F to 158°F)
 AFCs' high performance is due to the rate at which chemical reactions take place
 in the cell. They have also demonstrated efficiencies near 60% in space
 applications.
 The disadvantage of this fuel cell type is that it is easily poisoned by carbon
 dioxide (CO2). In fact, even the small amount of CO2 in the air can affect this
 cell's operation, making it necessary to purify both the hydrogen and oxygen
 used in the cell. This purification process is costly. Susceptibility to poisoning
 also affects the cell's lifetime (the amount of time before it must be replaced),
 further adding to cost.
 Cost is less of a factor for remote locations, such as space or under the sea.
 However, to effectively compete in most mainstream commercial markets, these
 fuel cells will have to become more cost-effective. AFC stacks have been shown
 to maintain sufficiently stable operation for more than 8,000 operating hours. To
 be economically viable in large-scale utility applications, these fuel cells need to
 reach operating times exceeding 40,000 hours, something that has not yet been
 achieved due to material durability issues. This obstacle is possibly the most
 significant in commercializing this fuel cell technology.




Phosphoric Acid Fuel Cells
 Phosphoric acid fuel cells use liquid phosphoric acid as an electrolyte²the acid is
 contained in a Teflon-bonded silicon carbide matrix²and porous carbon
 electrodes containing a platinum catalyst. The chemical reactions that take place
 in the cell are shown in the diagram to the right.
 The phosphoric acid fuel cell (PAFC) is considered the "first generation" of
 modern fuel cells. It is one of the most mature cell types and the first to be used
 commercially. This type of fuel cell is typically used for stationary power
 generation, but some PAFCs have been used to power large vehicles such as city
 buses.
 PAFCs are more tolerant of impurities in fossil fuels that have been reformed
 into hydrogen than PEM cells, which are easily "poisoned" by carbon monoxide
 because carbon monoxide binds to the platinum catalyst at the anode,
 decreasing the fuel cell's efficiency. They are 85% efficient when used for the
 co-generation of electricity and heat but less efficient at generating electricity
 alone (37%±42%). This is only slightly more efficient than combustion-based
 power plants, which typically operate at 33%±35% efficiency. PAFCs are also
 less powerful than other fuel cells, given the same weight and volume. As a
 result, these fuel cells are typically large and heavy. PAFCs are also expensive.
 Like PEM fuel cells, PAFCs require an expensive platinum catalyst, which raises
 the cost of the fuel cell.




Molten Carbonate Fuel Cells
Molten carbonate fuel cells (MCFCs) are currently being developed for natural
gas and coal-based power plants for electrical utility, industrial, and military
applications. MCFCs are high-temperature fuel cells that use an electrolyte
composed of a molten carbonate salt mixture suspended in a porous, chemically
inert ceramic lithium aluminum oxide (LiAlO2) matrix. Because they operate at
extremely high temperatures of 650°C (roughly 1,200°F) and above, non-
precious metals can be used as catalysts at the anode and cathode, reducing
costs.
Improved efficiency is another reason MCFCs offer significant cost reductions
over phosphoric acid fuel cells (PAFCs). Molten carbonate fuel cells can reach
efficiencies approaching 60%, considerably higher than the 37%±42%
efficiencies of a phosphoric acid fuel cell plant. When the waste heat is captured
and used, overall fuel efficiencies can be as high as 85%.
Unlike alkaline, phosphoric acid, and polymer electrolyte membrane fuel cells,
MCFCs do not require an external reformer to convert more energy-dense fuels
to hydrogen. Due to the high temperatures at which MCFCs operate, these fuels
are converted to hydrogen within the fuel cell itself by a process called internal
reforming, which also reduces cost.
Molten carbonate fuel cells are not prone to carbon monoxide or carbon dioxide
"poisoning" ²they can even use carbon oxides as fuel²making them more
attractive for fueling with gases made from coal. Because they are more
resistant to impurities than other fuel cell types, scientists believe that they
could even be capable of internal reforming of coal, assuming they can be made
resistant to impurities such as sulfur and particulates that result from converting
coal, a dirtier fossil fuel source than many others, into hydrogen.
The primary disadvantage of current MCFC technology is durability. The high
temperatures at which these cells operate and the corrosive electrolyte used
accelerate component breakdown and corrosion, decreasing cell life. Scientists
are currently exploring corrosion-resistant materials for components as well as
fuel cell designs that increase cell life without decreasing performance.
Solid Oxide Fuel Cells




 Solid oxide fuel cells (SOFCs) use a hard, non-porous ceramic compound as the
 electrolyte. Because the electrolyte is a solid, the cells do not have to be
 constructed in the plate-like configuration typical of other fuel cell types. SOFCs
 are expected to be around 50%±60% efficient at converting fuel to electricity. In
 applications designed to capture and utilize the system's waste heat (co-
 generation), overall fuel use efficiencies could top 80%±85%.
 Solid oxide fuel cells operate at very high temperatures²around 1,000°C
 (1,830°F). High-temperature operation removes the need for precious-metal
 catalyst, thereby reducing cost. It also allows SOFCs to reform fuels internally,
 which enables the use of a variety of fuels and reduces the cost associated with
 adding a reformer to the system.
 SOFCs are also the most sulfur-resistant fuel cell type; they can tolerate several
 orders of magnitude more of sulfur than other cell types. In addition, they are
 not poisoned by carbon monoxide (CO), which can even be used as fuel. This
 property allows SOFCs to use gases made from coal.
 High-temperature operation has disadvantages. It results in a slow startup and
 requires significant thermal shielding to retain heat and protect personnel, which
 may be acceptable for utility applications but not for transportation and small
 portable applications. The high operating temperatures also place stringent
 durability requirements on materials. The development of low-cost materials
 with high durability at cell operating temperatures is the key technical challenge
 facing this technology.
 Scientists are currently exploring the potential for developing lower-temperature
 SOFCs operating at or below 800°C that have fewer durability problems and cost
 less. Lower-temperature SOFCs produce less electrical power, however, and
 stack materials that will function in this lower temperature range have not been
 identified.
Regenerative Fuel Cells

 Regenerative fuel cells produce electricity from hydrogen and oxygen and
 generate heat and water as byproducts, just like other fuel cells. However,
 regenerative fuel cell systems can also use electricity from solar power or some
 other source to divide the excess water into oxygen and hydrogen fuel²this
 process is called "electrolysis." This is a comparatively young fuel cell technology
 being developed by NASA and others.



Polarization Curve
 The performance of a fuel cell is governed by its Polarization Curve.Ideal
 performance This type of performance curve shows the DC voltage delivered at
 the cell terminals as a function of the current density (current per unit area of
 membrane)being drawn by the external load.This curve and the losses
 associated with its shape will be discussed later. One measure of the energy
 conversion efficiency of a fuel cell is the ratio of the actual voltage at a given
 current density to the maximum voltage obtained under no load (open circuit)
 conditions.




Fuel Cell Efficiency
Since fuel cells use materials that are typically burnt to release their energy,the fuel
cell efficiency is described as the ratio of the electrical energy produced to the heat
that is produced by burning the fuel (its enthalpy of formation or hf).

From the basic definition of efficiency:   = W / Qin
where W is given by G (or NFE) Qin is the enthalpy of formation of the reaction
taking place. Since two values can often be computed depending on the state of the
reactant, the larger ofthe two values (³higher heating value´).

Gibb¶s Free Energy (chemical potential)

From our previous result for a cell operating reversibly: dH = TdS ± FEdN

Under these conditions: - the losses are minimal the useful work obtained is
maximized

This maximum work is represented by the Gibbs free energy: dG = -FEdN

So the thermodynamic expression for the maximum useful work obtained from a fuel
cell becomes: dG = dH ± TdS

Electrochemistry: Fuel Cell Reactions Hydrogen fuel cell:

Oxidation half reaction 2H2 4H+ + 4e-
Reduction half reaction O2 + 4H+ + 4e-    2H2O
Energy formation (kJ/mol) Cell reaction 2H2 + O2   2H2O

Methanol fuel cell: Cell reaction: CH4 + 2O2   CO2 + 2H2O
Maximum Fuel Cell Efficiency
The maximum efficiency occurs under open circuit conditions (reversible) when the
highest cell voltage is obtained.

  max =    Go /HHV= NFEo / HHV

For the hydrogen fuel cell reactions shown previously where Go was 237 kJ/mol and
 Ho was 286 kJ/mol, the maximum efficiency of the fuel cell would be 83%.



Benefits
 Benefits that fuel cells include:
      Physical Security
      Reliability
      Efficiency
      Environmental Benefits(ZERO POLLUTION )
      Battery Replacement/Alternative
      Military Applications


 Low to Zero Emissions
 Stationary Power
 A fuel cell running on pure hydrogen is a zero-emission power source. Some
 stationary fuel cells use natural gas or hydrocarbons as a hydrogen feedstock,
 but even those produce far less emissions than conventional power plants. Fuel
 cell power plants are so low in emissions that some areas of the United States
 have exempted them from air permit requirements. Fuel cells are also very
 quiet, which reduces noise pollution.




 Transportation
 Fuel cell vehicles are the least polluting of all vehicles that consume fuel directly.

       Fuel cell vehicles operating on hydrogen stored on-board the vehicles produce
       zero pollution in the conventional sense. Neither conventional pollutants nor
       green house gases are emitted. The only byproducts are water and heat.
       The simple reaction that takes place inside the fuel cell is highly efficient.
       Even if the hydrogen is produced from fossil fuels, fuel cell vehicles can
       reduce emissions of carbon dioxide, a global warming concern, by more than
       half.


High Reliability/High Quality Power
 Fuel cells can be configured to provide backup power to a grid-connected
 customer, should the grid fail. They can be configured to provide completely
 grid-independent power or can use the grid as the backup system. Modular
 installation (the installation of several identical units to provide a desired
 quantity of electricity) provides extremely high reliability in specialized
 applications. Properly configured fuel cells can achieve up to 99.9999%
 reliability, less than one minute of down time in a six year period.
 Fuel Flexibility
 Most fuel cells run on hydrogen and will continue to generate power as long as
 fuel is supplied. The fuel cell doesn't care where the hydrogen comes from, so a
 fuel cell system that includes a "fuel reformer" can generate hydrogen from
 diverse, domestic resources including fossil fuels, such as natural gas and coal;
 alcohol fuels, such as methanol or ethanol; from hydrogen compounds
 containing no carbon, such as ammonia or borohydride; or from biomass,
 methane, landfill gas or anaerobic digester gas from wastewater treatment
 plants . Hydrogen can also be produced from electricity from conventional,
 nuclear or renewable sources such as solar or wind.
  Security
 Because they don't have to be attached to the electric grid, fuel cells allow the
 country to move away from reliance on high voltage central station power
 generation which are the most likely terrorist targets in any attempt to cripple
 our energy infrastructure.
 Modularity/Scalability/Flexible Siting
 The beauty of fuel cells is their versatility - since they are scalable, fuel cells can
 be stacked until the desired power output is reached. Larger fuel cells can be
 linked together to achieve megawatt outputs. Fuel cells are quiet, which allows
 for siting close to business or residences. They are also durable and rugged, so
 they can withstand any terrain or weather conditions.


  Lightweight/Long-lasting Battery Alternative


 Fuel cells are being developed for portable electronic devices such as laptops,
 cellular phones, etc. Fuel cells are providing e a much longer operating life than
 a battery would, in a package of lighter or equal weight per unit of power
 output. The fuel cell doesn't require "recharging;" a liquid, solid, or gaseous fuel
 canister could be replaced in a moment. Fuel cells also have an environmental
 advantage over batteries, since certain kinds of batteries require special disposal
 treatment. Fuel cells provide a much higher power density, packing more power
 in a smaller space.
 Challenges to Fuel Cell Technology
 A fuel cell uses oxygen and hydrogen to produce electricity. The oxygen required
 for a fuel cell comes from the air. In fact, in the PEM fuel cell, ordinary air is
 pumped into the cathode. The hydrogen is not so readily available, however.
 Hydrogen has some limitations that make it impractical for use in most
 applications. For instance, you don't have a hydrogen pipeline coming to your
 house, and you can't pull up to a hydrogen pump at your local gas station.
Hydrogen is difficult to store and distribute, so it would be much more convenient if
fuel cells could use fuels that are more readily available. This problem is addressed
by a device called a reformer. A reformer turns hydrocarbon or alcohol fuels into
hydrogen, which is then fed to the fuel cell.
Unfortunately, reformers are not perfect. They generate heat and produce other
gases besides hydrogen. They use various devices to try to clean up the hydrogen,
but even so, the hydrogen that comes out of them is not pure, and this lowers the
efficiency of the fuel cell.
Some of the more promising fuels are natural gas, propane and methanol.
Many people have natural-gas lines or propane tanks at their house already, so these
fuels are the most likely to be used for home fuel cells. Methanol is a liquid fuel that
has similar properties to gasoline. It is just as easy to transport and distribute, so
methanol may be a likely candidate to power fuel-cell cars.



 Applications

 There are many uses for fuel cells ² right now, all of the major automakers are
 working to commercialize a fuel cell car. Fuel cells are powering buses, boats,
 trains, planes, scooters, forklifts, even bicycles. There are fuel cell-powered
 vending machines, vacuum cleaners and highway road signs. Miniature fuel cells
 for cellular phones, laptop computers and portable electronics are on their way
 to market. Hospitals, credit card centers, police stations, and banks are all using
 fuel cells to provide power to their facilities. Wastewater treatment plants and
 landfills are using fuel cells to convert the methane gas they produce into
 electricity. Telecommunications companies are installing fuel cells at cell phone,
 radio and 911 towers. The possibilities are endless.
Stationary
 More than 2500 fuel cell systems have been installed all over the world ² in
 hospitals, nursing homes, hotels, office buildings, schools, utility power plants -
 either connected to the electric grid to provide supplemental power and backup
 assurance for critical areas, or installed as a grid-independent generator for on-
 site service in areas that are inaccessible by power lines.
 Telecommunications - With the use of computers, the Internet, and
 communication networks steadily increasing, there comes a need for more
 reliable power than is available on the current electrical grid, and fuel cells have
 proven to be up to 99.999% (five nines) reliable. Fuel cells can replace
 batteries to provide power for 1kW to 5kW telecom sites without noise or
 emissions, and are durable, providing power in sites that are either hard to
 access or are subject to inclement weather. Such systems would be used to
 provide primary or backup power for telecom switch nodes, cell towers, and
 other electronic systems that would benefit from on-site, direct DC power
 supply.
  Landfills/Wastewater Treatment Plants/Breweries/Wineries- Fuel cells currently
 operate at landfills and wastewater treatment plants across the country, proving
 themselves as a valid technology for reducing emissions and generating power
 from the methane gas they produce. They are also installed at several breweries
 and a winery- Sierra Nevada, Kirin, Asahi and Sapporo and Napa Wine
 Company. Untreated brewery effluent can undergo anaerobic digestion, which
 breaks down organic compounds to generate methane, a hydrogen rich fuel.


 Transportation
Cars - All the major automotive manufacturers have a fuel cell vehicle either in
development or in testing right now, and several have begun leasing and testing
in larger quantities. Commercialization is a little further down the line (some
automakers say 2012, others later), but every demonstration helps bring that
date closer.
 Buses - Over the last four years, more than 50 fuel cell buses have been
demonstrated in North and South America, Europe, Asia and Australia. Fuel cells
are highly efficient, so even if the hydrogen is produced from fossil fuels, fuel
cell buses can reduce transit agencies¶ CO2 emissions. And emissions are truly
zero if the hydrogen is produced from renewable electricity, which greatly
improves local air quality. Because the fuel cell system is so much quieter than a
diesel engine, fuel cell buses significantly reduce noise pollution as well.
Scooters - In spite of their small size, many scooters are pollution powerhouses.
Gas-powered scooters, especially those with two-stroke engines, produce
tailpipe emissions at a rate disproportionate to their small size. These two-stroke
scooters produce almost as much particulate matter and significantly more
hydrocarbons and carbon monoxide as a heavy diesel truck. Fuel cell scooters
running on hydrogen will eliminate emissions - in India and Asia where many of
the population use them - this is a great application for fuel cells.
 Forklifts/Materials Handling - Besides reducing emissions, fuel cell forklifts have
potential to effectively lower total logistics cost since they require minimal
refilling and significantly less maintenance than electric forklifts, whose batteries
must be periodically charged, refilled with water, and replaced. Due to the
frequent starting and stopping during use, electric forklifts also experience
numerous interruptions in current input and output - fuel cells ensure constant
power delivery and performance, eliminating the reduction in voltage output that
occurs as batteries discharge.
 Auxiliary Power Units (APUs) - Today¶s heavy-duty trucks are equipped with a
large number of electrical appliances±from heaters and air conditioners to
computers, televisions, stereos, even refrigerators and microwaves. To power
these devices while the truck is parked, drivers often must idle the engine. The
Department of Energy (DOE) has estimated the annual fuel and maintenance
costs of idling a heavy-duty truck at over $1,800 and that using fuel cell APUs in
Class 8 trucks would save 670 million gallons of diesel fuel per year and 4.64
million tons of CO2 per year.
Trains - Fuel cells are being developed for mining locomotives since they
produce no emissions. An international consortium is developing the world¶s
largest fuel cell vehicle, a 109 metric-ton, 1 MW locomotive for military and
commercial railway applications.
 Planes - Fuel cells are an attractive option for aviation since they produce zero
or low emissions and make barely any noise. The military is especially
interested in this application because of the low noise, low thermal signature and
ability to attain high altitude. Companies like Boeing are heavily involved in
developing a fuel cell plane.
 Boats - For each liter of fuel consumed, the average outboard motor produces
140 times the hydrocarbonss produced by the average modern car. Fuel cell
engines have higher energy efficiencies than combustion engines, and therefore
offer better range and significantly reduced emissions. Iceland has committed
 to converting its vast fishing fleet to use fuel cells to provide auxiliary power by
 2015 and, eventually, to provide primary power in its boats.
  Portable Power
 Fuel cells can provide power where no electric grid is available, plus they are
 quiet, so using one instead of a loud, polluting generator at a campsite would
 not only save emissions, but it won't disturb nature, or your camping neighbors.
 Portable fuel cells are also being used in emergency backup power situations
 and military applications. They are much lighter than batteries and last a lot
 longer, especially imporant to soldiers carrying heavy equipment in the field.
 Consumer Electronics- Fuel cells will change the telecommuting world, powering
 cellular phones, laptops and palm pilots hours longer than batteries. Companies
 have already demonstrated fuel cells that can power cell phones for 30 days
 with out recharging and laptops for 20 hours. Other applications for micro fuel
 cells include pagers, video recorders, portable power tools, and low power
 remote devices such as hearing aids, smoke detectors, burglar alarms, hotel
 locks and meter readers. These miniature fuel cells generally run on methanol,
 an inexpensive wood alcohol also used in windshield wiper fluid.


BIBLIOGRAPHY

1) Non Conventional Energy Sources      by G. D. RAI
 2) Electronics For You (magazine)

				
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