Hybrid solid oxide fuel cells-gas turbine systems for combined heat and power: A review

This paper presents a review of the possible layout of hybrid power plants based on the integration of Solid Oxide Fuel Cells (SOFC) and Gas Turbine (GT) technologies. SOFC/GT plants were investigated by numerical and experimental analyses, thermo-economic optimizations, etc. Most of such systems are fed by methane converted by an internal reforming process into hydrogen and are based on the pressurized arrangement, showing lower capital costs and higher efficiencies. The steam required to drive the reforming reaction can be supplied by the anode recirculated stream or produced externally, by using the heat of exhaust gases. In this case, steam can be used also for thermal purposes and/or further system hybridization. More complex SOFC/GT configurations, including: IGCC SOFC/GT power plants, ORCs, and also hybrid SOFC/GT plants fed by alternative fuels (coal and biomass) are investigated. Finally an analysis of SOFC/GT control strategies and part-load performance is also presented.