Study on small-scale fuel-cell Co-generation system with methanol steam reforming considering partial load and load fluctuation

Abstract

Performance analysis and cost estimation are carried out for a co-generation system of solid high polymer film type fuel cell applied to a residential house. As the fuel, the fuel cell uses hydrogen which is generated by reforming and converting methanol. A removing system of carbon monoxide is incorporated after the reforming system. The system is uniquely designed to raise the fuel efficiency by changing the generated electricity by the cell to heat using electric heater for heat supply and reduces the fuel consumption of backup boiler. This concept shifts the operating point of the fuel cell system from partial-load condition to optimum operating condition, and the effectiveness is shown in the conditions of lower electricity demand and higher heat demand. Comparing the yearly cost of an averaged house in Hokkaido district, the energy cost of this system is shown to be 1.42 times as high as conventional systems in which co-generation system is not installed. This system becomes competitive when the price of methanol is reduced to 2/3 or 1/2.