OPTIMIZATION OF GAS PROCESSING FOR SOLIDE OXIDE FUEL CELL POWER PLANTS E. Riensche, U. Stimming and G. Unverzagt Institute of Energy Process Engineering (IEV ) Research Centre Jü lich (K FA ) D -52425 Jü lich, Germany ABSTRACT In order to benefit from the high electrochemical efficiency of solid oxide fuel cells, a skillfull balance of plant has to be developed. An energetic and economic analysis of a decentralized natural gas-fuelled SOFC-power plant in the range of 200 kW capacity is presented. Starting from a simple flowsheet process concepts with external and internal reforming and gas recycling by blowers or jet boosters are described. Cathode gas recycling by jet booster turns out to be more advantageous with respect to electricity production cost than gas recycling by hot gas fans. Cost analysis is applied to such plant concepts. 1. INTRODUCTION The energy conversion efficiency of fossil fuels has to be increased because of environmental concerns and preservation of dwindling resources. Fuel cell plants promise many advantages with respect to efficiency and environment. The application of solid oxide fuel cells (SOFC) in power plants for the generation of heat and power is desired for both application in small and large scale units because of the high operating temperature. But for a successfull market introduction also the operational efficiency has to be taken into account. V arious results of power plant optimization such as temperature differences in heat exchangers, numbers of fuel cells and also the electrical efficiency are combined into one final parameter, the cost of electrical energy production. Cost analysis could then lead to more economic rather than efficient power plant operation. The exact cost of energy production is a result of the assumptions in table 1 and may be discussed. But the aim is to show the influence of different power plant concepts on the electrical energy 1115 Proceedings of The Electrochemical Society, PV 1995-01, 1115-1122 (1995) DOI: 10.1149/199501.1115PV © The Electrochemical Society ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 207.241.231.81 Downloaded on 2019-04-26 to IP