EFFECT OF ENERGY INTERCHANGE SYSTEM BY USING FUEL CELLS CO-GENERATION IN APARTMENT COMPLEX

Abstract

 Fuel cells are being introduced in single-family homes, and it is also necessary to promote the introduction of collective housing located in city. In high·density urban areas such as Tokyo, there are many apartment buildings combined with other uses (apartment complex). However, energy interchange system with high energy saving performance in the multi·use condominiums is not considered.

 In this research, by utilizing the characteristics of energy consumption time fluctuation of both housing unit and facility unit in multi-family dwellings, especially apartment complex, by introducing FC-CGS, not only electricity but also heat can be interchanged in the entire residential building, an energy interchange system to meet each other, and aimed to clarify the optimum introduction capacity and energy reduction effect for the combination of different facilities and housing complexes is proposed. In order to verify the energy interchange effect between the housing unit and facility unit, the energy consumption of the 334 complex houses was surveyed in April-May and October-November 2018.

 Based on the results of the survey, an energy interchange system suitable for complex housing was proposed. In order to verify the flexible effects of the system, it is necessary to set up a building model for energy interchange, set the energy demand of the building, and set up installed equipment. A building model with an office on the fir st floor (175m²), 4 floors, 18 house units was set up for simulation. The household structure, the lifestyle, and the equipment performance were as three parameters when set the energy demand for each household. As representative examples, the facility units of office, restaurant and convenience store were examined. A solid oxide fuel cell with high power generation efficiency was adopted, and for the household unit, a fuel cell with a rated output of 0.7 kW for each household, 46% power generation efficiency and 43% exhaust heat recovery efficiency was introduced. Local establishment for local consumption was assumed for the setting of the energy interchange system. It enables power inter change in the building, supplies surplus power from the housing unit with low power consumption in the daytime to the facility unit, and sends power from the facility unit to the housing unit at night. The shortage will be assisted by grid power. As for heat transfer, the housing unit basically changes the waste heat of FC-CGS to hot water and uses it. When hot water in the hot water storage tank of the housing unit runs short, heat transfer was received from the hot water storage tank of the facility section. If there is a further shortage, it will be compensated by a backup water heater. Facility department was the opposite. When the hot water storage tanks in both the housing unit and the facility unit are fully stored, the radiator releases heat forcibly.

 Through simulation, the FC-CGS optimal introduction capacity and energy reduction rate of each type of complex house in summer and winter were obtained.