Cost Reduction Through Thermal Management Improvements in Large Scale Carbonate Fuel Cells

Cell area and power density are critical parameters that affect the cost of a fuel cell. Fuel cell stacks generate heat in addition to electricity and reaction products. In large area fuel cell stacks, internal cell temperatures and power density are determined by the effectiveness of heat removal. Fuel Cell Energy (FCE) has developed carbonate fuel cell power plants based on its Direct Fuel CellÔ (DFC) technology, which uses endothermic methane steam reforming for hydrogen generation and heat removal internally in the stack. Controlling internal reforming is an important part of thermal management. FCE has developed a three-dimensional stack simulation model that captures all the essential physics and predicts temperature, flow and compositional variations of different gas streams in the fuel cell stack. This model has been used to optimize thermal management resulting in a 20% reduction in stack thermal gradient and a 20% increase in power output.