1. Technical Seminar on FUEL CELLS
J.SRIKANTH(08FE5A0214)VIGNANS LARA INSTITUTE OF TECHNOLOGY &
SCIENCEVadlamudi , Guntur.
2. What is a Fuel Cell? A Fuel Cell is an electrochemical
device thatcombines hydrogen and oxygen to produceelectricity, with
water and heat as its by-product.
3. Why is Fuel Cell Technology Important? Since conversion of
the fuel to energy takesplace via an electrochemical process,
notcombustion. It is a clean, quiet and highly efficient
process-two to three times more efficient than fuelburning.
4. How does a Fuel Cell work? It operates similarly to a
battery, but it does not rundown nor does it require recharging As
long as fuel is supplied, a Fuel Cell will produce bothenergy and
heat A Fuel Cell consists of two catalyst coated
electrodessurrounding an electrolyte One electrode is an anode and
the other is a cathode The process begins when Hydrogen molecules
enterthe anode The catalyst coating separates hydrogens
negativelycharged electrons from the positively charged
protons
5. How does a Fuel Cell work? While the electrons pass
throughthe external circuit, oxygenmolecules pass through
thecathode There the oxygen and theprotons combine with
theelectrons after they have passedthrough the external circuit
When the oxygen and theprotons combine with theelectrons it
produces water andheat
6. Major Types of Fuel Cells Proton ExchangeMembrane (PEM) This
is the leading cell type forpassenger car application Uses a
polymer membrane asthe electrolyte Operates at a relatively
lowtemperature, about 175degrees Has a high power density, canvary
its output quickly and issuited for applications wherequick startup
is requiredmaking it popular forautomobiles Sensitive to fuel
impurities
7. Major Types of Fuel Cells Phosphoric Acid This is the
mostcommercially developedfuel cell It generates electricity atmore
than 40% efficiency Nearly 85% of the steamproduced can be used
forcogeneration Uses liquid phosphoric acidas the electrolyte
andoperates at about 450degrees F One main advantage is thatit can
use impure hydrogenas fuel
8. Major Types of Fuel Cells Molten Carbonate fuelcell Promises
high fuel-to-electricity efficiency and theability to utilize coal
basedfuels Require carbon dioxide andoxygen to be delivered to
thecathode Operates at extremely hightemperatures 1200 degrees
Primarily targeted for use aselectric utility applications
9. Major Types of Fuel Cells Solid Oxide Uses a hard,
non-porous ceramic compound as the electrolyte Can reach 60% power-
generating efficiency Operates at extremely high temperatures 1800
degrees Used mainly for large, high powered applications such as
industrial generating stations, mainly because it requires such
high temperatures
10. Major Types of Fuel Cells Alkaline Fuel Cell Used mainly by
military and space programs Can reach 70% power generating
efficiency, but considered to costly for transportation
applications Uses a solution of potassium hydroxide in water as the
electrolyte and operates at 75 -160 degrees Purification process of
the hydrogen and oxygen is costly
11. Major Types of Fuel Cells Regenerative Fuel Cells Currently
researched by NASA This type of fuel cell involves a closed loop
form ofpower generation Uses solar energy to separate water into
hydrogen andoxygen Hydrogen and oxygen are fed into the fuel
cellgenerating electricity, heat and water The water byproduct is
then re-circulated back to thesolar-powered electrolysers beginning
the processagain
12. Importance of Hydrogen Fuel Cells require highly purified
hydrogen asa fuel. Researchers are developing a wide range
oftechnologies to produce hydrogeneconomically from a variety of
resources inenvironmentally friendly ways.
13. Importance of Hydrogen Hydrogen is a secondary energy
resource,meaning it must be made from another fuel Hydrogen can be
produced from a widevariety of energy resources including: Fossil
fuels, such as natural gas and coal Nuclear energy Renewable
resources, such as solar, water, windand biomass
14. Hydrogen Production The biggest challenge regarding
hydrogenproduction is the cost Reducing the cost of hydrogen
production soas to compete in the transportation sectorwith
conventional fuels on a per-mile basis is asignificant hurdle to
Fuel Cells success in thecommercial marketplace
15. How will the hydrogen be stored? Developing safe, reliable,
compact and cost-effective hydrogen storage is one of thebiggest
challenges to widespread use of fuelcell technology Hydrogen has
physical characteristics thatmake it difficult to store large
quantitieswithout taking up a great deal of space
16. How will the hydrogen be stored? Hydrogen has a very high
energy content byweight (3x more than gasoline) and a very
lowenergy content by volume (4x less thangasoline) If the hydrogen
is compressed andcryogenically frozen it will take up a very
smallamount of space requiring a smaller tank, butit must be kept
super cold- around -120 to-196 degrees Celsius
17. How can Fuel Cell technology be used? Transportation
Stationary Power Stations Telecommunications Micro Power
18. How can Fuel Cell technology be used? Transportation All
major automakers areworking to commercialize afuel cell car
Automakers and expertsspeculate that a fuel cellvehicle will be
commercializedby 2010 50 fuel cell buses are currentlyin use in
North and SouthAmerica, Europe, Asia andAustralia Trains, planes,
boats, scooters,forklifts and even bicycles areutilizing fuel cell
technology aswell
19. How can Fuel Cell technology be used? Stationary Power
Stations Over 2,500 fuel cell systems have been installed all
overthe world in hospitals, nursing homes, hotels, officebuildings,
schools and utility power plants Most of these systems are either
connected to the electricgrid to provide supplemental power and
backup assuranceor as a grid-independent generator for locations
that areinaccessible by power lines
20. How can Fuel Cell technology be used? Telecommunications
Due to computers, the Internetand sophisticatedcommunication
networks thereis a need for an incrediblyreliable power source Fuel
Cells have been proven tobe 99.999% reliable
21. How can Fuel Cell technology be used? Micro Power Consumer
electronics could gaindrastically longer battery powerwith Fuel
Cell technology Cell phones can be powered for30 days without
recharging Laptops can be powered for 20hours without
recharging