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Fuel Cells: FAQs
By Peter Hemberger
What is a fuel cell?
During the 19th century, William Grove found that the energy produced by simple chemical reactions could be harnessed and exploited. His work led to the creation of the first alkaline one-kilowatt fuel cell system in the 1950’s. [1] The power producing potential of fuel cells was quickly adopted by NASA, which used them in the Gemini, Apollo, and space shuttle programs. [2] Since their use in the 1960’s space programs, fuel cells have been improved and are becoming commercially available in products such as cars, computers, cell phones, residential and small business power generators, and large scale stationary power generators. Fuel cells are also potential power providers for computers, credit card processing centers, jails, cellular towers, mining equipment, entertainment complexes, communication centers, navigation equipment, airports, road signs, defense installations, urban transit buses, and even vacuums. [3]
Fuel cells rely on a fairly simple chemical reaction to generate energy. While there are different kinds of fuel cells, all with their own unique characteristics, the general principle is the same across the board. A fuel cell is composed of an electrolyte sandwiched in between two electrodes. Electrodes are charged, usually metal, plates. The electrolyte is the substance that hydrogen protons freely pass through as they move between electrodes. Electrolytes are made of different substances and these different substances usually are what usually give different types of fuel cells their distinctive names.
The production of energy begins when a stream of hydrogen molecules is forced against the first electrode, called the anode, which is negatively charged. This anode forces the hydrogen molecule to split into protons and electrons. The protons are pulled through the electrolyte directly to the other electrode, called the cathode, which is positively charged. The electrons, having taken a different path around the electrolyte, are captured and used as an electrical current. These electrons then rejoin the protons in the cathode where they are both exposed to oxygen. The hydrogen and the oxygen combine to form pure potable water and some heat. [4] Often, through a process known as cogeneration, this waste heat is captured and utilized in the heating and cooling of the facility where the fuel cell is located.
The fuel cell is only one part of a complete standard fuel cell system. There are actually three main parts. These three main parts are the fuel reformer, the fuel cell stack, and the power conditioner. [5]
·The fuel reformer , usually through a process called steam reformation--a process that creates carbon emissions--isolates the pure hydrogen from a hydrocarbon fuel (methane, ethanol, propane, natural gas, etc…). This hydrogen, although pure, is sometimes referred to as “dirty hydrogen” due to the way it is created. [6] This hydrogen is then put into the fuel cell stack.
·The fuel cell stack is any number of fuel cells stacked together to increase the produced energy output. The energy created by the fuel cell stack is in the form of direct current.
·The power conditioner , or the inverter, is the mechanism that inverts the direct current produced by the fuel cell into alternating current. The inverting of direct current into alternating current is required for most power applications to work.
Why are fuel cells attractive as alternative energy generators?
Fuel cells are attractive as energy generators because of their:
·cleaner non-combustive operation. Fuel Cells emit no particulate matter and almost no NOx and SO2. While fuel cells still have some substantive CO2 emissions, they are only 45% that of coal generation and 47% the amount emitted from the production of energy using fossil fuels. [7]
·higher efficiencies when compared to combustion driven generators. Before even using cogeneration technologies in conjunction with the fuel cell, the cell is about 50%, and as much as 65%, efficient. [8] Using cogeneration can boost efficiencies to as high as 90%. [9] Compared to the 12-15% efficiency of most internal combustion engines, fuel cells are much more efficient. [10]
·ability to deliver reliable, uninterrupted power. In fact, a fuel cell in an integrated power supply system can deliver “six nines” or 99.9999% reliability. [11]
These are all welcome benefits in a time of unreliable polluting energy.
Are there different types of fuel cells?
There are various kinds of fuel cells. The basis of these different identities is founded on the difference in substance that is used as the electrolyte. This variation in electrolyte leads to different efficiencies, different heat outputs, and, therefore, preferred use in different applications. It is unlikely that one type of electrolyte will dominate all technology sectors, instead each type will probably fill specific technology niches depending on their relative advantages and disadvantages.
·Proton Exchange Membrane fuel cells (also known as PEM), which use a moist polymer membrane electrolyte, are the most common type of fuel cell. [12] PEM cells run at cooler temperatures, perhaps as low as 41 degrees F, with average temperatures of about 80 degrees F. [13] [14] This makes them ideal for portable fuel cell technologies and small scale residential applications. Their compact size, relatively low weight, quick start up, and ability to vary output to meet sudden shifts in power demands also make PEM fuel cells appealing to those looking to apply it in portable and smaller devices, light duty vehicles, and as replacements for rechargeable batteries. [15] [16] Their adverse qualities are high production costs and intense maintenance and repair requirements. [17] These are problems are not limited to PEM cells.
·Phosphoric Acid fuel cells (PA fuel cells) are another major type of fuel cell and are currently installed in over 200 systems globally. [18] PA fuel cells, which use an immobilized liquid form of phosphoric acid as its electrolyte, have higher operating temperatures of around 200 degrees C. [19] This warmer temperature makes cogeneration, using the steam produced as a byproduct, a somewhat more appealing option for those employing this type of fuel cell. However, this higher temperature also restricts the use of PA cells to more stationary applications. Personal electronic devices, such as cell phones, laptops, or even cars, would most likely not use PA fuel cells.
·Molten Carbonate fuel cells are a third type of fuel cell. They use an immobilized liquid form of an alkali carbonate mixture as an electrolyte. Molten Carbonate cells have even higher operating temps of around 650 degrees C. These cells are currently fueled by a wide variety of fuels including pure hydrogen, carbon monoxide, natural gas, propane, methane, marine diesel, and stimulate coal gasification products. [20] Stationary applications of these cells have been successfully demonstrated in Japan and Italy. [21]
·Solid Oxide (SO) fuel cells , which utilize a solid ceramic yttria stabilized zirconia electrolyte, have a much higher operating temperature of 980 degrees C or more. [22] For this reason, SO fuel cells are most often used in large high power applications such as industrial and large-scale electrical generating stations. [23] This type of fuel cell has the highest efficiency at about 60%. [24] Because of their high heat output, when cogeneration is used with SO fuel cell efficiencies can reach as much as 90%. [25]
·Other types of fuel cells include: Alkaline fuel cells, which were used by the NASA space program (with efficiencies of 70%); Direct Methanol fuel cells, which draw the hydrogen out of the methane without the assistance of a fuel reformer; and Regeneration fuel cells, which utilize a solar powered electrolyzer and their own waste water to form a self-contained regenerative system. [26]
Where do we get all of the hydrogen necessary to power fuel cells?
It is estimated that the typical household with a fuel cell system with a 40% efficiency, using 24 kWh per day, will need 21,500 ft3 of hydrogen a year to generate energy. [27] That is roughly 60 ft3 a day. This is a fair amount of hydrogen. Where is all of this hydrogen going to come from?
Hydrogen is the most abundant element in nature, however it is usually not found on its own but instead in conjunction with other elements. [28] For this reason, it is necessary to separate hydrogen out of substances that contain hydrogen. The most common substance thus far has been the hydrocarbon natural gas. Currently, the US uses more than 3.2 trillion ft3 of hydrogen per year, mostly derived from reforming natural gas. [29] While using natural gas in a fuel cell is better than using it in a combustion engine, it is still not renewable or emission free. In order to become totally renewable and emission free, a source of pure non-reformed hydrogen is needed. Research on a low cost and efficient way to obtain large amounts of hydrogen has been going on for some time now. While it is true that fuel cells have evolved with the help of non-renewable fossil fuels, it is imperative that we discover a way to produce pure (and therefore clean) hydrogen. An infrastructure, which can deliver and transport massive amounts of hydrogen safely and efficiently must also be developed. The following are some examples of the current techniques for capturing pure hydrogen.
There are four basic methods of obtaining pure (not extracted from fossil fuel hydrocarbons) hydrogen. The methods are: thermochemical, electrochemical, photoelectrochemical, and photobiological. [30]
·Thermochemical technologies use a steam reforming process to produce hydrogen from fuels such as gasified biomass, natural gas, coal, methanol, and gasoline. This includes processes that obtain hydrogen from switchgrass grown on marginal land. [31]
·Electrochemical techniques rely on the electrolysis of water to produce hydrogen. This is nothing more than passing an electrical current through the water.
·Photoelectrochemical processes split water, and hence produce hydrogen, by illuminating a water-immersed semiconductor with sunlight. “Clean hydrogen” (hydrogen not derived from fossil fuels) is most commonly produced using photoelectrochemical processes through the exploitation of solar panels. The solar panels produce electricity to electrically split water into hydrogen and oxygen through a process known as electrolysis. [32] However, the cost of solar panels does not make this process economically competitive with the production of hydrogen from fossil fuels. [33] It is perhaps better to just use the electricity straight from the solar panels, rather than using it to make hydrogen that will be used in fuel cells to make electricity.
·Photobiological methods use the natural photosynthetic activity of bacteria and green algae to produce hydrogen. This process is sometimes called biophotolysis. The University of Hawaii has built a processing plant with a development scale bioreactor. [34]
There are also some researchers that are using wind turbines to make electricity, which is then used to electrolyze (split) water, releasing pure hydrogen. [35]
Companies such as Teledyne Energy Systems produce machines that produce hydrogen. They can produce anywhere from 1 liter per minute to 200 m3 per hour. [36]
How much do fuel cells cost?
When looking for a solid statement of the cost of fuel cells, it is easy to be led astray by an array of various numbers. The confusion stems from the way in which costs are reported and by whom they are reported. Figures reported by governmental organizations may be most accurate and least biased. Furthermore, the cost can be in the form of the actual current cost or the, often hopeful, predicted cost of fuel cells in the future. Costs are also different when considering the application of the fuel cell. For instance, automotive costs are different from stationary costs. Below is a collection of the many kinds of cost that should be taken into account when considering the production of power using fuel cells.
·Current cost of fuel cells
The current cost of stationary fuel cells is variable. Costs as low as $2,000 per kW can be found [37] though, the presently available 3 kilowatt (5 kilowatt) PEM fuel cell manufactured by Avista labs of Spokane, Washington, costs $30,000. [38] Another large fuel cell producer, International Fuel Cells, advertises that their present cost for a commercial fuel cell power plant is $4,500 per kW. [39]
The current cost of fuel cells used in the automotive industry is quite comparable to that of fuel cells used in stationary applications. The present cost of an 80 kilowatt fuel cell, which is the size necessary to compete with a standard gasoline engine, is about $160,000. [40] With the cost of the average 80 kW gasoline engine at $3,500, this $2,000 per kW price tag of an automotive fuel cell is quite high. [41]
·Predicted future cost of fuel cells
The predicted costs of stationary fuel cells are also quite variable. Those making fuel cells hope to have prices down to around $500 per kilowatt by approximately 2005. [42] Nuvera, a large producer of stationary fuel cells, plans to release a 5 kilowatt fuel cell (7 kilowatt peak) in 2003 for around $5,000 [43] or an ambitious price of $1,000 per kilowatt. International Fuel Cells expects to introduce PEM power plants to the market by mid-2002 these plants are targeting a lower cost than their current $4,500 per kilowatt plants. [44]
The predicted cost of automotive fuel cells is a hopeful $50 per kW. This is the price Ballard hopes to reach in order to put in a bid to take over the $180 billion a year automotive engine market. [45] It is perhaps more likely that with in the next 10 years prices will decrease to $500 per kilowatt, if the future cost of automotive fuel cells is similar to that of stationary fuel cells. If the cost of production were to drop to $50 per kW, a fuel cell engine would be able to compete economically with gasoline engines.
·Cost at which it is economic for mass implementation/consumption of fuel cells
"A study by Arthur D. Little, Inc., predicted that when [stationary] fuel cell costs drop below $1,500 per kilowatt, they will achieve market penetration nationwide”. [46]
As was stated above, if the cost of production of automotive fuel cells were to drop to $50 per kW, a fuel cell engine would be able to economically compete with gasoline engines. Since the current price per kW is around $2,000, automotive fuel cell manufacturers will have to decrease the cost of production to 1/40th the current cost. This is a formidable challenge.
Besides the cost of producing a fuel cell system, which then determines the cost of purchasing a system, there is the cost of generating electricity while the system is in place. Currently the generation cost for a larger, 300 kW to 3 MW, Direct Fuel Cell system, which does away with the need for a fuel reformer, is between $0.08 and $0.10 per kilowatt-hour. Costs are projected to plummet to $0.05-$0.06 per kilowatt-hour by 2004. [47] (This data comes from a company trying to sell fuel cells and therefore may be overly optimistic and report a much cheaper price then is actually the case.)
What percentage of the world's electricity mix is generated by fuel cells?
As of 2001, fuel cells have a generating capacity of 75 megawatts. This is just a small fraction of global energy generation. However, according to a study done by Allied Business Intelligence, global fuel cell generating capacity is predicted to increase by a factor of 250, to more than 15,000 megawatts by 2011. [48] This is not an inconsequential amount.
Why aren’t more fuel cells being used today?
The main reason for the lack of use of fuel cells today is that fuel cells are relatively very expensive. The cost of producing and using fuel cells is so high because of the lack of mass production. Like any other young technology, it must be fine-tuned and then mass-produced before it becomes a more economic option for the consumer. [49] In addition, there are some general barriers to micropower in general that can be found in the micropower section of this web site, which are also barriers for fuel cells.
What are some current projections for fuel cell markets?
There are many examples of development in fuel cell technologies in spite of the barrier of high cost. Yet, these improvements are slow to get moving. For instance, in 1994 the largest manufacturer of fuel cells had a facility that built only 200 medium sized fuel cells a year. [50] Despite predictions in the mid 1990’s that fuel cell markets would exceed $3 billion by 2000, the fuel cell industry has not seen a huge boom, but has grown slowly. [51]By 2001, International Fuel Cells, one of the most well-known fuel cell manufacturers and sellers, had delivered little more than two hundred 200 kW fuel cell systems since 1991. [52] That is only 4 megawatts worth of plants per year globally. These relatively small numbers come from the company that lauds itself as “one of the largest companies in the world solely devoted to fuel cell technology” and “the world leader in fuel cell production and development”. [53]
Still, projections keep claiming the imminent boom in fuel cell markets. One recent study projects the global demand for fuel cell transportation in 2007 to be at $9 billion. [54] A report done by Allied Business Intelligence predicted that sales of fuel cells could grow to 15,000 MW a year by 2011. [55] Another report by Allied Business Intelligence predicted that the current $40 million stationary fuel cell market will grow to more than $10 billion by 2010. [56]
What are some current projects that use fuel cells?
The Connecticut USA Juvenile Training School in Middletown Connecticut has ordered a 1.2 MW fuel cell system, which will cost $18 million to install. The fuel cells were provided by International Fuel Cells who recently installed two smaller 200 kW units at a casino operated by the Mohegan tribe of Indians in Connecticut. [57]
The Connecticut Resources Recovery Authority is looking to install 12 fuel cell systems with a combined generation capacity of 26 megawatts and will cost an estimated $124 million. [58]
To find many more examples of new developments and projects that employ fuel cell technologies visit the Fuel Cell and Hydrogen News site.
What are some examples of fuel cell technologies or case studies online?
There is a multitude of sites on the Internet touting technologies that employ fuel cells. The following is a only small sample This is not an exhaustive list is a good starting point to learn more about fuel cell technologies online.
The Palm Desert Renewable Hydrogen Transportation Project, and the Schatz Hydrogen Generation Center is a demonstration site for the use of hydrogen vehicles. At this facility, a solar array is used to extract hydrogen from water, which is then distributed to hydrogen powered cars through a distribution center.
Ballard Power Systems, Motorola Mechanical Technology, Inc. and H-Power are currently looking at fuel cells to power small electronics, such as cell phones or laptop computers. These electronics will need to be “recharged” much less frequently, perhaps running 10 times longer than they would on standard battery power. [59] For more information, go to the United States Fuel Cell Council.
An environmentally helpful application of fuel cell technology is its use in landfills where methane constantly rises into the sky heating our atmosphere. ONSI is a large supplier of landfill fuel cell technology and has installed 140 US landfills with fuel cells and plans to install 750 more with the help of the EPA’s Landfill Methane Outreach Program. [60] Connecticut’s Groton Landfill has been using a land fill fuel cell to produce 600,000 kWh of electricity every year since 1996 with a continuous output of 140 kW; enough to power 100 homes. [61] It is estimated that a 1.5 million kWh per year landfill gas system can save a treatment plant approximately $102,000 annually. [62] For more information, visit Fuel Cells 2000.
To explore a variety of fuel cell applications visit the links below:
Various fuel cell vehicles
New international research and development information.
Smaller fuel cell vehicles such as bicycles and scooters.
hydrogen powered bicycles, vacuums, and more .
A German fuel cell submarine.
How do fuel cells affect the environment?
Fuel cells, when powered by pure clean hydrogen not acquired through the reformation of fossil fuels, are totally emissions free. The only products of the cell, besides electric current, are heat and pure potable H2O. Through cogeneration of the heat into steam and regeneration of the water using the process of electrolyzation, even these byproducts are utilized. In the case that they are not utilized, there is still no harm done to the surrounding environment.
The reality, however, is that pure hydrogen is rarely used except for in laboratory studies. Steam reformers are often used to isolate the hydrogen out of hydrocarbon fuels. Steam reformation is the process of combining steam with a hydrocarbon to isolate the hydrogen. The resulting CO2 emissions are lower than those from a combustion engine. Steam reformation emits zero to very small amounts of NOx and SO2. [63]
Even though the use of fossil fuels such as natural gas and propane is not totally emissions free and not renewable, the use of these fuels to power fuel cells is cleaner than the use of combustion engines and will allow for the continued improvement of fuel cells. Fuel cells are more environmentally sound than conventional energy technologies. Below is a comparison of the amount of pollution produced by fuel cells versus conventional energy technologies.
·Fuel Cell Engine vs. Gasoline Engine
In the US, passenger vehicles alone consume 6 million barrels of oil a day. [64] If 10,000 vehicles were to be powered by fuel cells, oil consumption would be reduced by as much as 6.98 million gallons per year. [65] According to the Department of Energy, if 10% of automobiles in the US were powered by fuel cells 60 million tons of CO2 would be kept from entering the atmosphere. [66] Furthermore, massive amounts of other greenhouse gases such as NOx and SO2 would be reduced as well as a lessened demand for the harmful drilling of oil amidst finely tuned fragile ecosystems.
·Fuel Cell Generation vs. Standard Coal and Oil Generation
Compared to the emissions created by conventional stationary power plants, fuel cells are much less emissive. Solid Oxide (SO) fuel cells emit .01 lbs. of NOx per MWh, while coal and oil generators both produce over 5 lbs. of NOx per MWh. SO fuel cells emit .005 lbs. of SO2 per MWh, while oil produces 11.6 and coal 13.4 lbs. of SO2 per MWh. SO fuel cells emit 950 lbs. of CO2 per MWh, whereas both coal and oil generation produces over 2,000 lbs. of CO2 per MWh. [67]
·Fuel Cell Generator vs. Diesel Generator
Compared to the emissions created by the most commonly used form of micropower, the diesel generator, fuel cells are much cleaner for the environment. Diesel generators produce enormously large amounts of NOx and particulate matter (PM-10) 21.8 lbs. and .78 lbs. per MWh respectively. This is far more than fuel cells’ almost zero emissions of these two climate-changing substances. [68]
Why don’t we put a fuel cell on the moon and beam the energy back to Earth?Although almost 1/3 of the moon’s thin atmosphere is composed of hydrogen, the idea of creating electricity that will have to be “beamed” 384,400 kilometers to be used is problematic at best. [69] [70] Using current non-StarTrek technology, electricity travels along transmission cables that are inefficient and very expensive: high voltage cables can cost thousands of dollars per mile, which is part of why there are people on earth that cannot get electricity. [71] Even if Bill Gates were to decide to fund such an operation, there exists no transmission cable that could maintain a current for the distance between the earth and the moon. Since even the best cables experience power losses of about 10% just between the standard earth-bound generating plant and its earthling customer, the electric current would never make the journey between the moon and the earth. [72] In addition, terrible tangling of the cables would occur due to the incongruent orbital and rotational patterns of the earth and the moon. It would be much more efficient and cost-effective to produce energy using fuel cells on the earth.
What are some policies that might promote the proliferation of fuel cells in the US?
In the US, some positive policy steps have been taken to aid in the development and proliferation of fuel cells. The US Dept. of Energy currently spends $50 million a year (FY1999) on research in Molten Carbonate and Solid Oxide fuel cells and $30 million a year (FY1999) for transportation applications. [73] The EPA has a program to facilitate the use of fuel cells at landfills and wastewater plants. [74] In 1995, Congress appropriated funds for the Department of Defense for a competitive Climate Change Fuel Cell Program. “This program grants funds to fuel cell power plant buyers to reduce the high initial cost of early production systems, providing up to $1,000 per kilowatt of power plant capacity not exceed one-third of total program costs, inclusive of capital cost, installation and pre-commercial operation”. [75] This program, for the last 6 years, has given more than $18.8 million in assistance for the purchase of 94 fuel cells and has therefore funded the first wave of commercialized fuel cell systems. [76] [77]
While these policies have been helpful there is still much more that could be done. The US has fallen behind Canada, Japan, and Germany, who are aggressively promoting fuel cells with tax credits, low-interest loans, and grants. [78]
The following policy moves would help the proliferation of fuel cells:
·Sales and property tax exemptions, which are already available for other renewable technologies
·Low interest loan programs
·Corporate and personal income tax credits and deductions
·Industry recruitment incentives
·Special grant programs [79]
·Major increases in research and development budgets of the DOE and DOT
·Direct governmental purchasing of early power plants and vehicles
·The continued “buying down” the cost of early fuel cell units installed across the country [80]
There are also many codes and standards for construction industries that need to be implemented, to make building inspectors, fire marshals, and code officials aware of installation and zoning requirements for these new technologies. Standardized codes for the generation, storage, and handling of fuel cells and their fuels are also needed. [81] Visit the International Code Council for more information.
Who are some of the big players commercially in fuel cells?
A few of the big players are:
3M of Minneapolis, Minnesota: A diversified materials and manufacturing company with $15 billion in annual sales, 3M makes membranes for proton-exchange membrane fuel cells.
Air Products and Chemicals, Inc. of Allentown, PA: A gas and chemical company with almost $5 billion in annual sales, this firm has developed processes to produce hydrogen from natural gas.
Avista Laboratories of Spokane, WA. An affiliate of Avista Corp. (formerly Washington Water and Power), a diversified energy company with $3.5 billion in annual revenue, Avista Labs is developing proton-exchange membrane fuel cells for residential applications.
Ballard Generation Systems of Vancouver, Canada: Ballard manufactures fuel cells, and enjoys strategic alliances with DaimlerChrysler, Ford, GPU International Inc. of New Jersey, France's ALSTOM SA and Japan's EBARA Corporation.
Energy Research Corporation of Danbury, Connecticut: ERC is a manufacturer of fuel cells and batteries with $24 million in annual revenue.
H Power of Belleville, NJ: A privately held developer of proton-exchange membrane cells for stationary and vehicular applications, H Power has three strategic shareholders: Quebec's Sofinov Société Financière D'Innovation, Singapore Technologies Automotive, Ltd. an
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60. Fuel Cells 2000 “Frequently Asked Questions”. http://216.51.18.233/fcfaqs.html Accessed July 3rd, 2001.
61. Fuel Cells 2000 “Frequently Asked Questions”. http://216.51.18.233/fcfaqs.html Accessed July 3rd, 2001.
62. Fuel Cells 2000 “Frequently Asked Questions”. http://216.51.18.233/fcfaqs.html Accessed July 3rd, 2001.
63. The Regulatory Assistance Project. “DG Emissions May 2001” http://www.rapmaine.org/DGEmissionsMay2001.PDF. Accessed July 9th, 2001.
64. Fuel Cells 2000 “Fuel Cell Basics”. http://216.51.18.233/index_e.html Accessed July 3rd, 2001.
65. Fuel Cells 2000 “Fuel Cell Basics”. http://216.51.18.233/index_e.html Accessed July 3rd, 2001.
66. Fuel Cells 2000 “Fuel Cell Basics”. http://216.51.18.233/index_e.html Accessed July 3rd, 2001.
67. The Regulatory Assistance Project. “DG Emissions May 2001” http://www.rapmaine.org/DGEmissionsMay2001.PDF. Accessed July 9th, 2001.
68. The Regulatory Assistance Project. “DG Emissions May 2001” http://www.rapmaine.org/DGEmissionsMay2001.PDF. Accessed July 9th, 2001.
69. “Apollo 17 Lunar Atmosphere Composition Experiments”. http://cass.jsc.nasa.gov/expmoon/Apollo17/A17_Experiments_LACE.html
70. Bill Arnett, “The Moon”. http://seds.lpl.arizona.edu/nineplanets/nineplanets/luna.html Accessed 19 June 2001.
71. American Wind Energy Association, “Wind Energy Fact Sheet: 10 Steps in building a wind farm”.
72. Greenhouse Gas Information Exchange, “Electric Transmission and Distribution Systems”. http://www.greentie.org/class/ixd02.htm. Accessed June 19th, 2001.
73. “Program Overview”. http://www.dodfuelcell.com/pro_summary.html Accessed July 3rd, 2001.
74. “Program Overview”. http://www.dodfuelcell.com/pro_summary.html Accessed July 3rd, 2001.
75. Bayer, Judith. “Why Should Congress and the Administration Support a Stationary Fuel Cell Tax
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76. “Program Overview”. http://www.dodfuelcell.com/pro_summary.html Accessed July 3rd, 2001.
77. Bayer, Judith. “Why Should Congress and the Administration Support a Stationary Fuel Cell Tax
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78. “Program Overview”. http://www.dodfuelcell.com/pro_summary.html Accessed July 3rd, 2001.
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80. “Program Overview”. http://www.dodfuelcell.com/pro_summary.html Accessed July 3rd, 2001.
81. “Fuel Cells Up to Code” Fuel Cell Quarterly Spring 2001 Volume 4 Issue 1.
82. All information on members of the fuel cell industry, other than Idatech and Nuvera obtained from: Serchuk, Adam and Virinder Singh. “Major Players”. A Sustainable Energy Industry Cluster for Mesa Del Sol. http://www.repp.org/articles/mesaDSol/ Accessed July 10th, 2001.
83. Idatech “Idatech Developing Compact 1kW Fuel Cell System”. http://www.idatech.com/features/compact_fuel_cell.html Accessed July 3rd, 2001.
84. Ballard “About Ballard”. http://www.ballard.com/products.asp Accessed July 3rd, 2001.
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