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An introduction to Fuel Cells Technology
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Fuel Cells
The Fuel Cell A Need for Change
Battery technologies are not keeping pace with demand
Battery life Miniaturization
Global warming A Possible Solution
Fuel Cell: A device that uses hydrogen (or a hydrogen-rich fuel) and oxygen to create an electric current
What Fuel Cells Do
Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries converted chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently
How Fuel Cells Work Hydrogen molecules
are delivered to the anode side of the fuel cell
Electrons are stripped from the molecules and forced to travel through a circuit, producing electricity
The leftover protons pass through the fuel cell and are recombined with the lost electrons on the cathode side, producing water molecules
Chemical energy of fuel and oxidizer
Combustionchamber
Fuel cell
Heat
Turbine or engine
Mechanicalenergy
Electricgenerator
Electric current
FC is an electrochemical device in which the energy of fuel and oxidant continuously supplied to electrodes is directly converted into electricity without low-efficient combustion process.
As there is no heat/power conversion in these devices, their energy efficiency is much higher than that of traditional power units, and can reach 90%.
Fuel Cells Vs Conventional Power Sources
How much hydrogen?
Transportation: gasoline yields 40 kJ/g average annual use: 500 gallons (4000
kg) energy use in one year: 1.6 108 kJ H2 yields 250 kJ/g, need 640 kg H2
Electricity: average annual energy use: 1.5 107 kJ H2 yields 250 kJ/g, need 60 kg H2
EACH PERSON IN US NEEDS ~700 KG OF H2!!
Sources of Hydrogen
Hydrocarbons: Oxidation: CH4 + 2 O2 CO2 + 2 H2O Still produces CO2!! Syn-gas: 2 CH4 + O2 2 CO + 4 H2
Produces CO that must be converted to CO2!!
Electrolysis of water remember H2 + O2 H2O, E = 1.23 V can be reversed H2O H2 + O2
Requires large amounts of energy!!
What does that mean?
WaterwasteWaterwasteElectricityElectricity
Supply ofHydrogenSupply ofHydrogen
A Timeline: Fuel Cell Implementation
1993: Ballard Power Systems launches first proof-of-concept hydrogen fuel cell bus, Vancouver
1996: Daimler Benz and Toyota are first major companies to unveil prototype fuel cell-powered passenger cars
2000: Ballard Power Systems unveils world’s first production-ready fuel cell for automotive use
2001: Honda opens the first hydrogen production and fueling station in Torrance, CA
2004: The World’s first fuel cell-powered submarine undergoes deep-water trials
MTI Micro Fuel Cells introduces a proof-of-concept fuel cell that runs handheld devices
1993: Ballard Power Systems launches first proof-of-concept hydrogen fuel cell bus in Vancouver
1970: Karl Kordesch builds the first practical fuel cell car
1965: NASA uses alkaline fuel cell in Apollo space missions
Late 1950’s: Allis-Chambers Manufacturing Co. demonstrates 20 hp fuel cell-powered tractor
1839: Sir William Grove invents the first fuel cell
Fuel Cells vs. Batteries Designed to be continuously powered
Fuel source can be re-supplied without interrupting power
Unlike batteries, the fuel source is not contained inside the fuel cell - increases shelf life and decreases time before replacement is necessary
Produces water waste only Environmentally friendly - companies such
as Dell must currently offer recycling programs for batteries in order to comply with government environmental regulations
More efficient than batteries
Benefits of Fuel Cells Environmental Reasons
Driving force Lowered emissions Less noisy
Higher quality Can be programmed for 99.999% uptime
More reliable On site No movable parts
More Benefits
Increased Efficiency Up to 80% with pure
Hydrogen With reformer about ~24-
32% Gasoline ~20% Battery-Powered ~26%
with recharging Distributed Generation Flexible Technology
Portable Modular
Some Limitations
Hydrogen: Not readily available, must use other
energy sources to convert Infrastructure not in place Difficult to store/distribute
High Capital Cost Non-technical barriers
Could have dramatic impact
Oil Industry & Hydrogen
Shell Royal Dutch Group $13 billion in capital investments for oil
production and exploration, while only having $243 million invested in all alternative energies combined.
Often recognized as a leading alternative energy conscious oil company.
Why is Shell involved in alternative energies?
Automotive Industry & Hydrogen
GM and others are looking to capitalize on the next generation of cars After enormous success of rivals like
Honda and Toyota with hybrid vehicles GM, along with other domestic
automotive makers Face serious threats of bankruptcy,
making a large R&D push difficult. Rivals such as Toyota and Honda are
already ahead of GM and Ford
•A 30 ft. Hydrogen Fuel cell powered transit bus made by Ballard Power Systems in Canada.
•It has a 275 horsepower engine, and a range of 250 miles before requiring refueling.
•The only emission from this bus is warm, moist air.
Honda FCX
Operates between -20C and 95C.
Honda has also built a hydrogen production and filling station prototype.
Ford FCV
Driving range 100 miles.
H2 Fuel Cell
Ford H2RV
H2 Internal Combustion Enginehybrid with electric motor.
Driving Range 125 miles.
Future2015 – 2025- Substantial markets for
hydrogen-powered vehicles likely to start developing
2020: 5 to 10 million hydrogen-powered cars
2030: 50 million hydrogen powered cars
2040: 150 million hydrogen-powered cars