FUEL CELL FAQ

What is a fuel cell?
Like a battery, a fuel cell is a device that produces electricity and, in some cases, heat through an electrochemical process. An important difference is that though a battery has a finite life and has to be recharged, a fuel cell can provide power continuously as long as is has a supply of fuel.

What is a solid oxide fuel cell?
A Solid Oxide Fuel Cell (SOFC) is a high temperature, ceramic device that can convert fuel directly into electrical energy without the use of intermediate combustion processes and mechanical conversion devices. As a result, the SOFC uses less fuel and produces less carbon dioxide than conventional power sources such as internal combustion engines, jet engines, and steam turbines.

What types of fuel cells are there?

Alkaline - AFC
Phosphoric Acid - PAFC
Molten Carbonate - MCFC
Polymer Electrode Membrane - PEMFC
Solid Oxide - SOFC

Of the above technologies, PEMFCs and SOFCs are the two most applicable to small scale systems. SOFCs are widely regarded as the superior technology for stationary applications since:

SOFCS are more efficient.
In actual tests using natural gas as a fuel, SOFCs are over 45% efficient in making electricity, while PEM fuel cells are less than 25% efficient.
SOFCs can operate on fuels available today.
PEMFCs require hydrogen to operate, which necessitates an external reformer and hydrogen separator. This makes the use of other fuels such as methane and natural gas inefficient. SOFCs on the other hand can reform a wide variety of fuels using steam created as a by-product of the reaction. Additionally, the solid oxide cells are tolerant to CO and thus SOFCs do not require expensive catalysts to remove traces of CO.
SOFCs have a longer life
The stack life of SOFCs has been proven to be much longer than PEMFCs. Demonstrations is the 100kW class have been operational for over 16,000 hours and showed no signs of degradation in power output. It is anticipated that SOFCs show the best promise for achieving the reliability necessary to meet commercial needs. Stack life of 50,000 to 100,000 hours is entirely feasible and attainable in the near term. By contrast, the average life of 90 PEM fuel cells tested by the Army Corps of Engineers was just 3,000 hours

What are the advantages of SOFCs?
In general, all fuel cells are characterized as being low noise, low polluting, and highly fuel-efficient compared to conventional power sources. However, the SOFC has its own specific set of additional advantages over other types of fuel cells. A number of these advantages are listed below:

SOFCs can provide electrical efficiencies of 45 - 50%. Due to their high operating temperatures, cogeneration cycles can be effectively employed, with the resulting efficiencies of these cogeneration power plants approaching 90%.
SOFC cell elements are constructed from ceramic materials. The raw ingredients for these ceramics are relatively inexpensive.
Given the high operating temperatures of SOFCs, the need for expensive precious metal catalysts is negligible.
SOFCs can operate on hydrocarbon fuels such as natural gas, diesel fuel, and jet fuel with minimal fuel processing.
Hydrogen-rich gases containing carbon monoxide do not need to undergo additional “gas clean-up” steps.

What are SOFCs made of?
Acumentrics' SOFCs anodes are made of nickel oxide and yttrium stabilized zirconia (YSZ). The tube is coated with and electrolyte layer made of yttrium stabilized zirconia. For the outer layer, a cathode of lanthanum manganite is applied. All layers are made through simple ceramic manufacturing processes such as extrusion, dip coating, and sintering which allows Acumentrics to have a very low cost manufacturing process.

What fuels can Acumentrics' SOFC operate on?
Acumentrics’ systems operate on today’s fuels and have been run on natural gas, ethanol, propane, reformed low sulfur diesel, syngas, and biofuels, and have the ability to run on pure hydrogen if it becomes easily available. Efforts are under way to demonstrate operation on JP-8 and bio-diesel.

What size of system does Acumentrics manufacture?
At present, Acumentrics manufactures a 5kW system that can operate on a variety of fuels. The company plans to introduce a 2kW combined heat and power system in the 4th quarter, 2007 (the Acumentrics Home Energy Alternative Device – AHEAD).

Who are Acumentrics' competitors?
Other companies that produce small scale SOFC systems Ceramic Fuel Cells in Australia, Ceres Power in the UK, BloomEnergy in California and Versa Power in Colorado. Certain PEM manufacturers such as Plug Power in New York, Ballard in Canada and Idatech in Oregon are also developing products that are in the 1-5kW range.

How is Acumentrics technology different from its competitors?

Able to start and stop quickly (minutes v. hours for competing units)
Highly efficient ( over 45% vs. < less than 30% for the more familiar PEM fuel cells)
Fuel flexible, operating on today’s fuels rather than waiting for hydrogen (demonstrated on natural gas, ethanol, propane, reformed low sulfur diesel, and syngas, with no sensitivity to carbon monoxide—a poison for other fuel cells)
Tolerant of repeated thermal cycling (over 100 v. fewer than 15 for others)
Designed to be inexpensively manufactured, with no high-cost catalysts and no exotic materials. (The equipment to automate the process is conventional and well known.)

How many systems has Acumentrics’ sold?
Since 2001, Acumentrics has sold and fielded over thirty systems in the 500W to 5kW range. Systems have gone to strategic investors as well as universities, national parks, and system integrators. Acumentrics works hand in hand with its customers to site the units and provide operational support during the customer’s test plan.

Where can I buy a system?
Today only field demonstration units are available. If you believe you want one please contact Bob Tomasetti at btomassetti@acumentrics.com. Information regarding desired size of system, application, available fuel, and location will be appreciated and allow us to provide you a quicker response.

How much does a system cost?
List price for a 5 kW unit is $175,000. Present systems are still demonstration units and carry the cost associated with not only the system itself but some custom engineering which typically results from each customer’s intended installation. Acumentrics normally provides site installation support and monitoring which is also provided in the quotation.

Can I buy shares in Acumentrics?
Acumentrics is a private company and its shares are not traded on any exchange.

What is CHP?
CHP means Combined Heat and Power. Energy conversion devices generally generate both electricity and heat. In most large power plants, traditionally only the electricity was fed into the grid and the heat was not utilized. CHP means using both the electricity generated from a fuel, thus allowing more efficient use of all the energy stored in the fuel.

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