The document describes different types of fuel cells, including polymer electrolyte membrane (PEM) fuel cells, alkaline fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, and solid oxide fuel cells. It provides details on the electrolyte, catalyst, operating temperature, and electrical efficiency of each type of fuel cell. The document also discusses the basic components and function of hydrogen fuel cells, as well as some advantages and disadvantages of fuel cells and their applications.

1. FUEL CELL USING NON-CONVENTIONAL
SOURCE OF ENERGY
MADE BY :-
VIPLAV
&
ROHIT

2. A fuel cell is a device that converts the
chemical energy from a fuel into
electricity through a chemical reaction
with oxygen or another oxidizing agent.
HYDROGEN is the most common fuel,
but hydrocarbons such as natural gas
and alcohols like methanol are sometimes
used.

3. • Anode
– Negative post of the fuel cell.
– Conducts the electrons that are freed from the hydrogen molecules so that they
can be used in an external circuit.
– Etched channels disperse hydrogen gas over the surface of catalyst.
• Cathode
– Positive post of the fuel cell
– Etched channels distribute oxygen to the surface of the catalyst.
– Conducts electrons back from the external circuit to the catalyst
– Recombine with the hydrogen ions and oxygen to form water.
• Electrolyte
– Proton exchange membrane.
– Specially treated material, only conducts positively charged ions.
• Catalyst
– Special material that facilitates reaction of oxygen and hydrogen
– Usually platinum powder very thinly coated onto carbon paper or cloth.
– Rough & porous maximizes surface area exposed to hydrogen or oxygen
Parts of a Fuel Cell

4. 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 :-
1) Polymer Electrolyte Membrane (PEM) Fuel Cells
2) Alkaline Fuel Cells
3) Phosphoric Acid Fuel Cells
4) Molten Carbonate Fuel Cells
5) Solid Oxide Fuel Cells

5. A membrane separates the anode and cathode serving as both
the electrolyte and a catalyzer for the conduction of protons.
PEMFCs can use hydrogen gas or some alcohols such as
ethanol or methanol as fuels. This type of fuel cell runs at
low temperatures, under 200 degrees Fahrenheit and has a
wide variety of applications, including automotive vehicles
(including busses and forklifts), unpiloted military vehicles,
residential primary or backup power, portable charging for
electronics (laptops, cell phones), and distributed generation
power plants
Electrolyte: Solid polymer membrane
Catalyst: Platinum is the most active catalyst for low-temperature fuel cells
Operating Temperature: Around 175-200⁰F
Electrical Efficiency: 40-60 percent
Polymer Electrolyte Membrane (PEM) Fuel Cells

6. These fuel cells use a solution of potassium hydroxide in water as the
electrolyte. High temperature AFCs operate at temperatures between
100 and 250 degrees Celsius but through advancements in technology,
some AFC can operate at temperatures between 23 and 70 degrees
Celsius. AFC require pure hydrogen and pure oxygen as the reactants
due to possible CO2 pollution that could affect the cell’s
operation. Although they require pure inputs of fuel, AFC operate at
efficiencies of nearly 60%. These fuel cells have mostly been used in
remote locations, like in underwater vehicle and in outer space.
Electrolyte: Potassium hydroxide solution in water
Catalyst: Can use a variety of non-precious metal catalysts
Operating Temperature: Around 225-475⁰F
Electrical Efficiency: 60-70 percent
Alkaline Fuel Cell (AFC)

7. Phosphoric Acid Fuel Cells
The electrolyte used in PAFCs is liquid phosphoric
acid. PAFCs operate at temperatures of 300-400
degrees Fahrenheit. The fuel used in PAFCs is
hydrogen which must be reformed outside of the fuel
cell. Electrical generating efficiencies range
between 37 and 42% but when used as a CHP
system, the efficiencies increase to
90%. Applications of PAFCs in stationary power
generation.

8. Electrolyte: Typically consists of alkali (Na & K) carbonates retained in a
ceramic matrix of LiHO2
Catalyst: High MCFC operating temperature permits the use of lower-cost, non-
platinum group catalysts
Operating Temperature: Around 1,200 ⁰F
Electrical Efficiency: 50-60 percent
The high operating temperatures of MCFCs means
that hydrocarbon fuels can be converted to hydrogen within the fuel cell itself
(internal reforming). MCFCs are not prone to CO or CO2 “poisoning”
they can even use carbon oxides as fuel – making them more attractive for fueling
with gases made from coal. MCFCs are ideal for large stationary power
and CHP applications, and are available as commercial products, with dozens of
power plants deployed at food and beverage processing facilities, manufacturing
plants,
hospitals, prisons, hotels, colleges and universities, utilities, and wastewater
treatment plants worldwide.
Molten Carbonate Fuel Cell (MCFC)

9. Electrolyte: A solid ceramic
Catalyst: High SOFC operating temperature permits
the use of lower-cost, non-platinum group catalysts
Operating Temperature: About 1,800⁰F
Electrical Efficiency: 50-60 percent
High-temperature SOFCs are capable of internal
reforming of “light” hydrocarbons such as natural gas,
but heavier hydrocarbons (gasoline, jet fuel) can be
used, though they require an external reformer.
Solid Oxide Fuel Cells (SOFC)

11. The hydrogen fuel cell operates similar to a battery. It has two
electrodes, an anode and a cathode, separated by a membrane.
Oxygen passes over one electrode and hydrogen over the
other.The hydrogen reacts to a catalyst on the electrode anode
that converts the hydrogen gas into negatively charged
electrons (e-) and positively charged ions (H+).
The electrons flow out of the cell to be used as electrical
energy. The hydrogen ions move through the electrolyte
membrane to the cathode electrode where they combine with
oxygen and the electrons to produce water. Unlike batteries,
fuel cells never run out.

12. Fuel Cell Efficiency
• 40% efficiency converting methanol to
hydrogen in reformer
• 80% of hydrogen energy content converted
to electrical energy
• 80% efficiency for inverter/motor
–Converts electrical to mechanical energy
• Overall efficiency of 24-32%

13. Disadvantages
Little more efficient than alternatives
Technology currently expensive
Many design issues still in progress
Hydrogen often created using “dirty” energy
(e.g., coal)
Pure hydrogen is difficult to handle
Refilling stations, storage tanks, …
Advantages
Water is the only discharge (pure H2)
Advantages/Disadvantages of Fuel Cells

14. Applications
More than 2500 fuel cell systems have been installed all over the world — in hospitals, nursing
homes, hotels, office buildings, utility power plants. Portable fuel cell systems supply power for
cars, submarines, spacecraft, etc.; charging batteries for digital cameras, mobile phones etc.
1. Emergency power systems
Emergency power systems are a type fuel cell system, which may include lighting, generators
and other apparatus, to provide backup resources in a crisis or when regular systems fail. They
find uses in a wide variety of settings from residential homes to hospitals, scientific laboratories,
data centers, telecommunication equipment and modern naval ships.
2. Uninterrupted power supply
An uninterrupted power supply provides emergency power and, depending on the topology,
provide line regulation as well to connected equipment by supplying power from a separate
source when utility power is not available.
3) Cogeneration
Cogeneration can be used when the fuel cell is sited near the point of use, its waste heat can be
captured for beneficial purposes. Micro combined heat and power is usually less than 5 Kw for a
home fuel cell or small business.
4) Portable Power Systems
Portable power systems that use fuel cells, can be used in the leisure sector , the industrial
sector (i.e. power for remote locations including gas/oil well sites, weather stations etc.), or in
the military sector.