Advances in solid oxide fuel cells and integrated power plants

Abstract

In the last ten years, the solid oxide fuel cell (SOFC) development programme at Westinghouse has evolved from basic material science to the development of fully integrated electric power systems. Since 1986, 11 such systems have accumulated over 45 000 operating hours including 25 kWc atmospheric SOFC systems installed at customer sites in the United States and Japan. A 100 kWe atmospheric SOFC power system is being delivered to a European consortium in 1997. By pressurizing SOFC systems and integrating the fuel cells with a combustion turbine, efficiencies of between 60 and 70 per cent (net LHV, or lower heating value) can be attained. SureCELL™ plant concept designs are being evaluated at 3, 5 and 10 MWe. The plants are characterized by the high efficiencies noted, low emissions, a compact modular design and excellent performance over a wide range of operating conditions. The cost of electricity studies indicates that the integrated plants have a 30–45 per cent economic advantage over similar sized combustion turbine systems. A 3 MWe SureCELL™ SOFC-combustion turbine integrated power system is planned to be operational by the end of this decade.