Release Date: March 31, 2000

A commercial design of an advanced fuel cell - the building block of a family of environmentally super-clean, fuel-flexible power plants - has passed several milestones in a joint public-private development effort.

The Direct FuelCell is a versatile, combustion-less power source being developed in the Department of Energy's fuel cell research program. It can use natural gas, methanol, ethanol, bio-gas or other hydrogen-rich fuels.

FuelCell Energy, Inc. has completed one year of commercial design validation and endurance testing of a 250 kilowatt-class Direct FuelCell^TM (DFC^TM) power plant at the Danbury, Connecticut headquarters. The "direct" in the name refers to internal conversion of fuel gas to hydrogen instead of externally in a separate unit. This approach reduces costs and makes more efficient use of what would have been wasted excess heat.

The demonstration included the longest running (8600 hours) carbonate fuel cell fuel cell stack ever as well as the largest. Beginning operation in February 1999, this grid connected power plant used a full-size stack of 340 nine-square foot area cells. The stack was manufactured at the company?s state-of-the-art production facility in central Connecticut. This stack is the building block for FuelCell Energy's family of commercial products ranging in size from 250 kilowatts to 3 megawatts.

The next step toward commercialization will be field trials of the packaged submegawatt product.

"FuelCell Energy's one-year anniversary of the start up of this advanced power plant is a major milestone in our efforts to develop the clean energy systems of tomorrow," said Rita Bajura, Director of the National Energy Technology Center. The Center is the primary technical arm for the Energy Department's Fossil Energy advanced power systems program.

"This is not a small scale laboratory experiment but rather a full-sized, grid-connected power plant that has been powering FuelCell Energy's own facilities and providing power to the local utility grid for a year," Bajura said. "It has been running in an unattended mode for the past eight months and has operated exactly as designed, delivering clean, high quality electric power efficiently, quietly and reliably."

In parallel with its Danbury stack validation testing, FuelCell Energy has been negotiating and starting field trials for benefit of interested customers. Negotiations have resulted in commitments for sub-megawatt field trials planned for a Mercedes Benz automobile production site in Tuscaloosa, AL and for a site served by the Los Angeles Department of Water and Power.

Meanwhile, field trials of the sub-megawatt FuelCell Energy stack successfully started in Europe in November 1999 at Bielefeld, Germany by the company's European partner, MTU, a unit of Daimler-Chrysler. The MTU unit provides 225 kilowatts of electricity with utilization of waste heat. The unit showed overall thermal efficiency of 77% with 45% fuel-to-electricity efficiency.

All of the demonstrations, including the Danbury system operate on pipeline natural gas. In the DFC^TM pipeline gas is directly fed to the fuel cell stack, which results in a simple reliable and cost-effective system.

The Danbury plant uses a full-size stack (the commercial building block) and operates at atmosphere pressure. Multiples of the basic stack building block will be used by FuelCell Energy to construct megawatt-class power plants. The achievement is significant for both the 250 kilowatt- and megawatt-class power plant types because no further scaleup of stack size is required for commercialization.

During the one-year operation, the plant has delivered more than 1.3 million kilowatt-hours of electricity. It was intentionally subjected to six thermal cycles (including one with fuel supply loss simulated), different types of emergency trips, and other robustness tests.

This new power generation system's ability to respond to load demand in seconds has also been demonstrated.

The Danbury power plant operation verified that the DFC^TM exhaust is cleaner than the U.S. Clean Air Act standard. The emissions of nitrogen oxides, sulfur oxides, and carbon monoxide are <0.1 ppm, <0.01 ppm, and <1.0 ppm respectively.

In a similar parallel test of full-scale cells, an 8 kilowatt DFC stack has logged 14,000 hours on multiple types of fuels, helping to verify the logevity and fuel versatility of the technology.

Dr. Mark Williams, the Energy Department's Fuel Cell Product Manager at NETL said, "The potential value of fuel cells is already widely recognized. We are very pleased with the operational ruggedness of FuelCell Energy's 250 kilowatt system as a whole and the endurance results of the prototype commercial cells in particular."

Dr. Williams said that the next steps to commercialization of the DFC's are field trials currently underway and high volume manufacturing required for lower cost commercial production.

The milestones are part of the U.S. Department of Energy's Cooperative Agreement with FuelCell Energy. The program is managed by National Energy Technology Laboratory in Morgantown, WV and Pittsburgh, PA, under the DOE Fossil Energy. Its goals are to enable industry to take advantage of fuel cells by reducing costs and enhancing performance, and to strengthen the nation's economy by developing American leadership in manufacturing fuel cell systems.