1. 1. Technical Seminar on FUEL CELLS J.SRIKANTH(08FE5A0214)VIGNANS LARA INSTITUTE OF TECHNOLOGY & SCIENCEVadlamudi , Guntur.
2. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 17. How can Fuel Cell technology be used? Transportation Stationary Power Stations Telecommunications Micro Power
18. 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. 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. 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. 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
22. 22. Fuel cell power plant
23. 23. Typical Hydrogen Power Plant
24. 24. Some other applications
25. 25. Some other applications
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