Fossil and nuclear fuel reserves are becoming
increasingly limited, and the world's energy future will
have to include several renewable alternatives to these
The present reliance on energy from fossil fuels produces
unwanted side effects: environmental pollution, carbon
dioxide emissions that accelerate global warming.
Geopolitical tensions arising from the non uniform
distribution of fossil resources throughout the world.
The challenge is to find highly efficient ways to produce,
deliver, and use energy that enhance quality of life but do
not threaten the environment and climate.
3. Status of Hydrogen Today
Hydrogen is the most abundant element in the
universe, it does not naturally exist in its elemental
form on Earth.
Pure hydrogen must be produced from other
hydrogen-containing compounds such as fossil fuels,
biomass, or water
Current leading technology for producing hydrogen in
large quantities is steam reforming of methane gas.
4. PRODUCING HYDROGEN
There are many viable means to produce H2. Some
common methods are;
5)Photocatalytic water splitting
7. Storage and delivery
Physical storage: liquefaction , compression, physisorption
Chemical storage: metal hydrides, complex hydrides.
Suppliers currently transport hydrogen by pipeline or
over roadways using tube trailers or cryogenic liquid
For a given volume, hydrogen contains a smaller amount
of useable energy than other fuels such as natural gas and
Because of its low volumetric energy density, hydrogen is
comparatively more costly to transport and store.
8. Fuel cells
Fuel cells now in development will provide
a new way to produce power, especially in
Fuel cells are electrochemical devices like
A fuel cell does not run down or require
Conversion of the fuel to energy takes
place via an electrochemical process, not
combustion .It is a clean, quiet and highly
efficient process- two to three times more
efficient than fuel burning.
9. Fuel cell : Principle
• A fuel cell consists of two electrodes
sandwiched around an electrolyte.
•Spurred by a catalyst, hydrogen
oxidizes into hydrogen protons and
give up its electrons to the electrode,
which thereby becomes the anode. This
buildup of negative charge then follows
the path of least resistance via the
external circuit to the cathode.
•flow of electrons through a circuit that
•As the electrical current begins to
flow, hydrogen protons pass through
the membrane from the anode to the
cathode, react with oxygen at the
cathode to form water and heat.
Anode Reaction: H2 —> 2 H+ + 2 e-
Cathode Reaction: ½ O2 + 2 H+ + 2 e- —> H2O
10. Types of fuel cells
Different types of fuel cells are classified by the kind of electrolyte used
Polymer Electrolyte Membrane (PEM) :Perfluoro sulfonic acid.
Alkaline (AFC) : Aqueous solution of KOH soaked in a matrix .
Phosphoric Acid (PAFC) : Phosphoric acid soaked in a matrix.
Molten Carbonate (MCFC) : Solution of lithium, sodium, and/ or
potassium carbonates, soaked in a matrix ‘
Solid Oxide (SOFC) : Yttria stabilized zirconia.
Stationary power generation
Transportation – No pollution
Portable power – Miniature Fuel Cells
13. Why hydrogen
and fuel cells?
No dependence on foreign oil
Zero to near-zero levels of harmful emissions .
Fuel Cell vehicles can be up to 3 times more efficient
than internal combustion engines.
Very less noise generated .
Honda FCX Clarity
14. Disadvantages of hydrogen fuel
More energy to make hydrogen than you get from it.
Hydrogen powered cars will not be able to store as
much fuel as a normal car.
It is not a very good fuel for an internal combustion
Will not perform as well in colder environments.
15. Future Scope
Power Plants using direct solar & hydrogen fuel cells.
The size and weight of current fuel cell systems must
be reduced to attain market acceptance, especially
This does not exist today, but when technology catches
up with the idea, we will see hydrogen being used in
fuel cells for heating, cooling and electrical.