Evaluation of a solid oxide fuel cell and gas turbine combined cycle with different cell component materials

A system model integrating a solid oxide fuel cell and a gas turbine (SOFC/GT system) was constructed. Based on the constructed model, we have carried out comprehensive evaluations of various candidate materials for SOFC cell components. An optimization study was carried out so that SOFC/GT system can achieve the highest efficiency at certain conditions. For the evaluation, a cathode supported tubular type cell was selected as cell structure, and operation temperature was set at 800degreesC. We have optimized the system for several sets of cathode/electrolyte/anode materials. System cost and efficiency were obtained for each set of cathode/electrolyte/anode materials as a result of the optimization. SOFC/GT system using yttria stabilized zirconia electrolyte turned out to be economically competitive at the operation temperature of 800degreesC although further lowering of overpotentials are needed to achieve higher output power density. Evaluations carried out for several candidate materials for SOFC cell components indicated the suitable materials for the construction of a low cost system. Several methods for lowering the system cost were also evaluated. The constructed model can be used as a platform for comprehensive evaluation of various candidate materials for SOFC cell components.