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Polymer electrolyte and solid oxide are the two fuel cell types (PEFC, SOFC) under development in Switzerland. The very distinct operating temperatures of 80°C (PEFC) and 800–950°C (SOFC) impose fundamentally different requirements upon the nature of the fuel; normally purified H2 for the former (CO trace) and usually synthesis gas for the latter (H2, CO as main constituents). Apart from stored hydrogen, the most relevant fuels are primary hydrocarbons (natural gas, biogas, liquids,...), that then need processing (chemical conversion, cleaning) up to a level compatible with the fuel cell catalysts. These processes are briefly reviewed. Fuel compositions with an emphasis on impurities are given. Two application examples from Swiss R&D are presented: gasoline conversion to high purity H2 for PEFC and contaminated biogas processing for SOFC.

Solid Oxide Fuel Cell (SOFC) application development is very well represented in Switzerland by two companies. Sulzer Hexis AG is one of the world leaders in the commercialization of SOFC systems for single family houses. A smaller company, HTceramix, is active in novel processing routes for cells and in innovative stack designs. This article first presents the benefits of implementing SOFC in selected applications and markets. Then the current state-of-the-art in stacking is described for both Swiss stack designs, looking at power density, and electrical efficiency. It is remarkable that both stacks currently exhibit a unique characteristic in SOFC design: the absence of side sealing, which permits to significantly simplify the stack assembly and thus improve its reliability. Finally, the two generations of SOFC systems produced by Sulzer Hexis are presented. The HXS 1000 Premiere preseries system is evaluated on the basis of the extended demonstration program currently underway where 110 systems are in operation in single family houses and public buildings. The near-series system is then introduced with respect to the identified needs in reduction of investment and operating costs as well as size and weight.