Solid Oxide Fuel Cells Running on Landfill Gas

Solid oxide fuel cells (SOFCs) are promising electrochemical devices for efficient power generation at a high temperature (typically 800°C). SOFCs exhibit several advantages due to the high operating temperature and oxygen ion conducting electrolyte: (1) fast reaction rate; (2) low cost catalyst materials; (3) suitable for combined heat and power cogeneration or trigeneration; (4) fuel flexibility – in principle all combustible fuels can be used in SOFCs, including hydrogen, natural gas, renewable biofuels, ammonia. In this study, the landfill gas in HK is considered as a fuel for SOFC. A mathematical model is developed to capture the physical and chemical processes in a planar SOFC, by integrating a computational fluid dynamics (CFD) model with a chemical model and an electrochemical model. The transport and reaction phenomena in the cell are all considered, including the mass transfer, heat transfer, methane steam reforming (MSR) reaction, methane carbon dioxide reforming (MCDR) reaction, water gas shift reaction (WGSR), and electrochemical reactions. The results reveal that the use of landfill gas in SOFCs for power generation is technically feasible in Hong Kong.