In the race to speed solid oxide fuel cell (SOFC) technology out of niche markets and into widespread commercial use, GE Hybrid Power Generation Systems has kicked fuel cell performance into high gear. Recent advancements have dramatically improved baseline cell performance and accelerated GE’s prospects for achieving the system efficiency and cost objectives of DOE’s Solid State Energy Alliance (SECA) program.
Packing more power into smaller volumes is one of the breakthroughs needed to reduce the cost and expand the use of efficient, environmentally friendly fuel cells. However, increasing power density isn’t the only goal; as power density increases, fuel cells must continue to efficiently and reliably convert fuel to electric power.
GE researchers have done both with the development of full-size single-cell SOFC modules that consistently achieve a power density of 404 mW/cm² at 88% fuel utilization. This far surpasses their SECA Phase I goal of 300 mW/cm² and represents a 47% increase over their 2004 baseline performance. The cells have also demonstrated stable operation at 95% fuel utilization—a record for full-size planar solid oxide fuel cells.
GE Hybrid Power Generation Systems is one of six industrial teams developing solid oxide fuel cells under the Office of Fossil Energy’s SECA program. The program was initiated in the fall of 1999 as an alliance between government, industry and the scientific community to develop solid oxide fuel cells that could eventually be sold in virtually every market needing clean, affordable electric power. GE joined SECA in 2001 and is nearing the end of the first of three phases in the research, development and testing of complete 3-kW to 10-kW SOFC prototypes.
The GE cells are fabricated using GE’s tape calendaring process, a mass-production manufacturing technique that supports the $400-per-kilowatt system cost goal of the SECA program. At $400 per kW—nearly one-tenth the cost of power-generating fuel cells currently sold on the market—fuel cells would compete with traditional gas turbine and diesel electricity generators for stationary applications and become viable auxiliary power suppliers for the transportation sector.
GE’s SOFC technology has been incorporated into a SECA prototype fuel cell system. The compact, fuel-flexible system operates now on methane, and will be able to operate on pipeline natural gas, coal gas, propane and other fuels in the future. To optimize performance and reliability, the system uses an integrated thermal management approach in which internal components that generate heat are connected with those that use it, so energy is not lost to the environment. The system also employs a flexible control structure that allows the system’s operating characteristics to be easily adjusted. Prototype testing began in April 2005.