For reduction of Green house Gas emissions, Polymer Electrolyte Membrane Fuel Cells (PEFC) is promoted by the government in Japan as more efficient co-generation system (CGS). On this study for the purpose of finding the efficient energy supply system with PEFC in the apartment house, first the author proposed “PEFC Apartment House” as more efficient system than the current one (boiler and electric power), which consists of PEFC-CGS, thermal storage tanks, power network and management system. Second, in order to develop the planning method of facilities with PEFC, the author has built up a database of PEFC performance by carrying out measurements at a residential house, and has developed an environmental and economical evaluation system. Third, for prediction of energy conservation and environmental effect of “PEFC Apartment House”, with the evaluation system the author has predicted annual primary energy consumption and carbon dioxide emissions at a 30-unit apartment house in Tokyo. As a result, the author estimated about 14% reduction of annual primary energy consumption and about 28% reduction of carbon dioxide emissions. At last, in order to confirm an economical condition to compose this system, the relation between the price of the city gas and the profit of the energy supplier was examined. As a result, it was found that if the city gas unit price falls up to about 2.4 [yen/MJ], the profit is added and if the city gas unit price falls up to about 1.4 [yen/MJ], the investment collection years would become ten years or less.

Units: SI