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Fuel Cells: The Energy Technology of the Future. Charlie Lee October 26, 2005. Presentation Highlights. Overview of fuel cell technologies Major federal and state activities Overview of solar energy Overview of wind energy Recommendations for Taiwan. Fuel Cell Video Clips. Bush talk
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Fuel Cells: The Energy Technology of the Future Charlie Lee October 26, 2005
Presentation Highlights • Overview of fuel cell technologies • Major federal and state activities • Overview of solar energy • Overview of wind energy • Recommendations for Taiwan
Fuel Cell Video Clips • Bush talk • Fuel Cell Technologies
What Is a Fuel Cell? • A fuel cell is an electrochemical device that converts the chemical energy of a fuel directly into electrical energy without combustion. Its byproducts are pure water, CO2, and heat • The basic physical structure of a fuel cell consists of an electrolyte layer in contact with a porous anode and cathode on either side. • The basic process is (1) gaseous fuels are fed continuously to the anode (negative electrode) and (2) an oxidant (i.e., oxygen from air) is fed continuously to the cathode (positive electrode); electrochemical reactions take place at the electrodes to produce an electric current.
Fuel Cell Prospective • Has higher energy efficiency, thus reducing petroleum dependence • Has lower multi-media emissions, thus reducing the risk on human health and the environment • Avoids major investment in transmission and distribution systems • Establishes a new industry worth billions of dollars in sales and hundreds of thousands of jobs • Is a green technology which is both environmentally and economically sustainable
How do FCs Compare to IC engine? • Fuel cell (FC): A device that converts fuel chemical energy to electricity by an electrochemical process • Internal combustion (IC) engine: A device that converts fuel chemical energy to thermal energy to generate mechanical work or electricity by a combustion process • Efficiency: FC ranges 50-??% and IC engine 30-35% which is limited by the Carnot cycle
Estimated Efficiencies of Engine Cycles Using Liquid Hydrocarbon Fuels
Fuel Cell Technologies • Low temperature FC (<200 C) • Alkaline fuel cell (AFC) • Direct methanol fuel cell (DMFC) • Phosphoric acid fuel cell (PAFC) • Proton exchange membrane fuel cell (PEMFC)
Fuel Cell Technologies • High temperature FC (>500 C) • Molten carbonate fuel cell (MCFC) with external reformer • Solid oxide fuel cell (SOFC) with external reformer • Molten carbonate fuel cell (MCFC) with internal reformer • Solid oxide fuel cell (SOFC) with internal reformer • Hybrid fuel cell (HFC): Micro-turbine with any of the 4 high-temperature FC
12 Major Fuel Types • Gasoline • Propane • Natural gas • Methanol (liquid, derived from natural gas) • Ethanol (liquid, derived from corn products)
Major Fuel Types(Continued) • Biogas (derived from agricultural products or energy crops) • Anaerobic digestion gas • Landfill gas • Diesel fuel • Coal fuel • Electrolysis by solar energy • Electrolysis by wind energy
Pressure Differences • Ambient pressure FC (1 atm) • 12 (fuel types) x 12 (fuel cell types) = 144 combinations • High pressure FC (10 atm) • 12 (fuel types) x 12 (fuel cell types) = 144 combinations • Subtotal potential FC combinations = 288 combinations • If cogeneration is included, the potential total combinations = 576 combinations
Direct Methanol Fuel Cell (DMFC) • Fuel: Liquid methanol • Electrolyte: A solid polymer membrane (a thin plastic film) • Operating Temperature: 50 - 120 C • Anode reaction: CH3OH + H2O CO2 + 6H+ + 6e- • Cathode reaction: 6H+ + 3/2O2 + 6e- 3H2O • Overall reaction: CH3OH + H2O + 3/2O2 CO2 + 3H2O
DMFC Development Status • In the United States • Fuel Cell Energy Inc. was awarded a contract to build one-MW power plant, which consists of four 250-kilowatt Direct Methanol Fuel Cell units (FC Today2005/08/02). • UltraCell Corporation has developed a new portable reformed methanol fuel cell that has twice the energy density of lithium batteries (2005/08/26). • In Europe • SFC, a German fuel cell supplier, recently announced the introduction of a European methanol fuel distribution network that will begin this month making the company's methanol fuel cartridges available at more than 200 sales points across the continent (2005/08/18).
Proton Exchange (Polymer Electrolyte) Membrane FC (PEMFC) • Fuel: Hydrocarbons. The cells are not sulfur- or CO- tolerant. • Electrolyte: A proton-conducting membrane (a solid thin plastic film) • Operating temperature: Less than 200 C • Anode reaction: H2 2H+ + 2e- • Cathode reaction: ½O2 + 2H+ + 2e- H2O • Overall reaction: H2 + ½O2 H2O
PEMFC Development Status • Automakers with the California Fuel Cell Partnership advance the PEMFC technology almost daily • Best candidate for automotive power applications • Compared to other types of fuel cells, PEMFCs generate more power for a given volume or weight of fuel cell. • The operating temperature is less than 200 C, which allows rapid start-up.
PEMFC Application • DOE Project Objectives • Develop 120-ton, 1 MW Army fuel cell locomotive • Total Cost: Estimated US$12 million for 5 years, beginning 2003
PEMFC Application • DOE Project Objectives • Develop a fuel cell-powered mine loader. • Total Cost: Estimated US$7.6 million for 3 years, beginning 2002
Solid Oxide FC • Fuel: Hydrocarbons • Electrolyte: A thin, solid ceramic material (solid oxide) that is conductive to oxygen ions (O2-). Its advantage: There is no liquid electrolyte, thus avoiding its associated corrosion and electrolyte management problems. • Operating temperature: 600 - 1000 C • Anode reactions: H2 + O2- H2O + 2e-; CO + O2- CO2 + 2e- • Cathode reaction: O2 + 4e- 2O2- • Overall reaction: O2 + H2 + CO H2O + CO2
SOFC Development Status • For tubular cells: Westinghouse has been developing this technology since the late 1950s. This tubular SOFC is being demonstrated at user sites in a complete, operating fuel cell power unit of nominal 25 kW (40 kW max) capacity. • For flat plate cells: Companies pursuing these concepts in the U.S. are Allied Signal Aerospace Company, Ceramatec, Inc., Technology Management, Inc., and Ztek, Inc. There are a number of companies also in Japan, in Europe, and one in Australia developing these fuel cells.
Major U.S. Federal and State FC Activities • U.S. Department of Energy • Fuel cell technology development • Hydrogen production • U.S. Department of Defense • Fuel cell for military application • U.S. Environmental Protection Agency • Environmental fuel cell life cycle analysis • State of California
US EPA Fuel Cell Environmental Life Cycle Analysis (LCA) • Determine how Clean fuel cells are, compared to other power systems • Determine how Safe fuel cells are (less health and environmental risk) • Conclusion: This study is to help environmental agents (e.g., EPA and State permit writers) determine how fuel cell applications should be regulated from the viewpoint of CAA, CWA, RCRA and PPA.
Fuel Cell LCA Study Objective and Outputs conventional power pollutants or risk reduction pollutants or risk FC power 100 % fuel displacement
Boundary Conditions • Set the US electricity grid air emissions to 0% (baseline) for each air emission type in the figure. • For the purposes of this study, the boundaries of the life cycle are a 1 kW SOFC operating for 40,000 hours at 100% load
Major California Fuel Cells Organizations • California Fuel Cell Partnership (CaFCP) • California Stationary Fuel Cell Collaborative • California Hydrogen Highway Initiative • California Sunline Transit Agency
California Fuel Cell Partnership (CaFCP) • Mission: • Promoting fuel cell vehicle commercialization as a means of moving towards a sustainable energy future • Increasing energy efficiency • Reducing or eliminating air pollution and greenhouse gas emissions.
CaFCP Government Members • Federal Government • Department of Energy • Department of Defense • Department of Transportation • Environmental Protection Agency • State Government • State of California
CaFCP Industrial Members and Their FC Vehicles • Chrysler: F-Cell • Ford: Focus • GM: Hydrogen • Honda: FCX • Hyundai: Santa Fe FCEV • Nissan: Xterra • Toyota: FCHV
California Stationary Fuel Cell Collaborative (CaSFCC) • One of the goals of the Collaborative is to implement an inter-organizational policy to utilize fuel cells in government facilities such as the Cal/EPA Headquarters building shown in the next photo. • Members represent a group of key organizations interested in combining efforts and resources towards commercialization of stationary fuel cells in California. These organizations formed a Core Group, which is developing a program of activities towards its mission.
California Hydrogen Highway Initiative • "I am going to encourage the building of a hydrogen highway to take us to the environmental future... I intend to show the world that economic growth and the environment can coexist. And if you want to see it, then come to California...“ by Governor Arnold Schwarzenegger, State of the State Address, January 6, 2004.
