ESTIMATION ENERGY SAVING EFFECTS OF SHARING FUEL CELL WITH TWO HOUSEHOLDS BY SIMULATION PROGRAM

Abstract

This purpose of this report is to develop methods of introducing fuel cells to households of apartments. We proposed a method of sharing one fuel cell between two households and estimated the effects by a simulation. The goal of this technique is to level the load, to sum up two households' loads, and to increase generation efficiency and waste heat efficiency. This technique of sharing a fuel cell between two households could provide considerable merits of the following: · Households of apartments tending to consume less energy than households of detached houses. · The initial cost would be half if one fuel cell could cover the load of two households. · This method does not require large scale renewal constructions or rebuilding. · This system can utilize control systems which have already been used for existing products. No new control logics need to be developed. Firstly, we developed simulation programs of SOFC·PEFC based on actual measurement data, product catalogs and results of previous studies. This program calculated electric power generation, gas usage and waste heating usage of fuel cells, using input information of electricity usage and hot water usage by households as well as weather conditions. Calculation interval was one minute. It was written in Visual Basic. We reproduced, with calculation results of this report, the latest model of fuel cell. Characteristic points are shown below: · The volumes of the tanks were smaller in comparison with assumptions in previous studies. The volume of the PEFC tank was one hundred and forty liters and the volume of the SOFC tank was twenty-eight liters. · Waste heat collected from the power generating unit was not used for the hot water floor heating system. The number of waste heat users was lower than previous products. This content is shown in the second chapter. In the next step, we performed a questionnaire survey of households living in apartments in Fukuoka City and made data of quantity of electricity and hot water to input to simulation. We replicated the life of households living in apartments in Fukuoka City. The virtual households for simulation included households consisting of one person and households consisting of one couple. This content is shown in the third chapter. Lastly, using constructed simulation programs and input data, we examined two cases: one fuel cell used by one household and one fuel cell shared by two households. We estimated the effects of saving energy. We verified from the calculation results that sharing system was more competent in saving energy in comparison with the case of one fuel cell used by one household. It was proved that SOFC shared by small-sized households was especially effective in saving energy. This was because the load factor of power generation increased in summing up the loads of two households. These content and future tasks are shown in the fifth chapter.