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SEMINAR ON
“ POWER GENERATION USING FUEL CELL”
Submitted to:
Jitender Soni
(prof.)
Presented by:
Vivek kumar Meena
(EE,8th sem)
FOSSIL FUEL
RENEWABLES
OTHER
COAL
OIL
NATURAL GAS
SOLAR PV / THERMAL
HYDRO
WIND
NUCLEAR
BIO - MASS
FOCUS ON FUEL CELLS
OUR PRESENT LIFESTYLE CANNOT DO AWAY WITH FOSSIL FUEL ENERGY
SOURCES IMMEDIATELY.
BUT, ADOPTING ENERGY CONVERSION SYSTEMS WITH HIGHER EFICIENCY WILL
REDUCE THE GAS GENERATION.
FUEL CELLS MEET THIS REQUIREMENT ADEQUATELY.
ALSO, BEING A COMBUTIONLESS SYSTEM THERE IS NO EMISSSION OF SOX/NOX.
Parts of a Fuel Cell• 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.– Membrane blocks electrons.
• 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
Fuel Cell
Fuel Cell Operation
• Pressurized hydrogen gas (H2) enters cell on anode side.
• Gas is forced through catalyst by pressure. – When H2 molecule comes contacts platinum catalyst, it splits into two
H+ ions and two electrons (e-).
• Electrons are conducted through the anode– Make their way through the external circuit (doing useful work such as
turning a motor) and return to the cathode side of the fuel cell.
• On the cathode side, oxygen gas (O2) is forced through the catalyst– Forms two oxygen atoms, each with a strong negative charge. – Negative charge attracts the two H+ ions through the membrane, – Combine with an oxygen atom and two electrons from the external
circuit to form a water molecule (H2O).
HOW ACTUALLY FUEL CELL WORK
Fuel Cell Type Temp of Operatio
n [oC]
Unit Sizes [kWe]
Most likely applications
Alkaline Fuel Cell (AFC) RT – 100 < 100 Space , Military recently
terrestrial applications
Proton Exchange Membrane Fuel Cell (PEMFC)
RT – 100 0.1 - 100
Portable devices like Lap Tops, Cellular phones, Video Cameras etcDomestic & Dedicated Power (+ heat) Buses, Passenger Cars, Service Vehicles, Railway Locomotives & Streetcars etc
Phosphoric Acid Fuel Cell (PAFC)
100 – 2105 - 200 (also MW sized plants)
Dedicated Power (+ heat), Railways
Molten Carbonate Fuel Cell (MCFC)
650100 - 2,000 (plants up to 100 MW)
Dispersed Power & Utility Power (Combined Cycle -with downstream Steam Turbine)
Solid Oxide Fuel Cell (SOFC)
800-10002.5 – 250(plants up to 100 MW)
Domestic & Commercial (heat and power), Utility Power (combined cycle) Mobile applications for railways
Types of Fuel Cells
PEMFC AFC PAFC MCFC SOFC
Electrolyte Ion ExchangeMembrane
PotassiumHydroxide
Phosphoric Acid
Molten carbonates
CeramicOxides
Catalyst Platinum non platinum
Platinum Nickel Perovskite
Operating Temp 0 C
RT-80 RT-80 180-205 650 800-1000
ElectricalEfficiency(%LHV)
32-40
50-60 36-42 45-60 50-60
Applications
Cogeneration √ √ √Utility Power √ √ √
Distributed Power
√ √ √ √
Passenger Vehicles
√ √
Heavy DutyVehicles
√ √
Portable Power
√ √
Specialty Power
√ √
PEMFC AFC PAFC MCFC SOFC
Advantages High Power density,Light weight, quick response
Low cost high efficiency,Co tolerant
Co tolerance up to 1.5%Multi fuel capability
Inexpensive catalystsMulti fuel capability
Efficiencies up to 60%
Disadvantages Humidification requiredCOIntolerancePlatinum&Membrane pushes the cost upwards
Requires inlet air scrubbers.CirculatingAlkali requires toping up
Expensive platinum catalyst used.Low current& power.Large size& weight
High temperatures enhance corrosion and the breakdown of cell components.
High tempenhance corrosion
Alkaline Fuel Cell Applications
PEMFC applications
MCFC &DFC applications
World's First Fuel Cell-Gas Turbine Hybrid now Operating in California
220-kW hybrid system with a Solid Oxide Fuel Cell (SOFC) generator and a down-stream micro-turbine
SOFC stack
Part II : FUEL CELL IN INDIA
Fuel Cells at BHEL (History of Development)
• 1987-1990: Started work on PAFC. Made single cells and small stacks (100-200 cm2)
• 1991: Demonstrated a 1 kW stack (chlor-alkali plant, 40 cells,with imported bipolar plates, ~400 cm2)
• 1995: Demonstrated 5 kW stacks (chlor-alkali plant, 80 cells, ~900 cm2, Laminated bipolar plates, 300*400 mm, Rolled electrodes)
• 2001: Demonstrated 2*25 kW stacks (chlor-alkali plant, 160 cells / stack, ~1600 cm2, molded bipolar plates, screen printed electrodes)
• 2002:Acquired basic PEMFC technology ,single cell testing
The 50kW Power Pack during testing at
BHEL R&D during December 2000
Fuel Cells Application in IndiaCommercial establishments
Shops in Malls and Underground bazaars1 to 3 kW systems / around 1,00,000
Small Business Establishments5-10 kW systems / 50,000
Entertainment Industry25-50 kW systems / 500 to 1,000
Hotels, restaurants & Resorts100-200 kW systems / up to 500 units
Hospitals 200-500 kW systems / up to 200 unitsResidential Complexes
50-200 kW systems / 30,000 to 50,000
Distributed Generation
- Rural (Remote areas)- Urban ( Hotels ,Hospitals ,Colleges,
Software development centres)- Strategic (Communication centres , Defense,
Chemicals and Pharmaceutical plants)
Fuel options
Urban :- Hydrogen,NG,Methanol,LPG,
Di-gas
Rural :- Ethanol ,Biogas
Strategic:- Hydrogen, NG, LPG, Methanol
Technology of fuel cells will depend upon the type of fuel available
CONCLUSION………
Current worldwide electric power production is based on a centralized, grid-dependent network structure. This system has several disadvantages such as high emissions, transmission losses, long lead times for plant construction, and large and long term financing requirements .
Fuel cells have many advantages over conventional power generating equipment: high efficiency, low emissions, siting flexibility, high reliability, low maintenance, excellent part-load performance, modularity, and multi-fuel capability. Because of their efficiency and environmental advantages, fuel cell technologies are viewed as an attractive 21st century solution to energy problems.
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