This paper describes the results of experiments and analyses on introducing residential combined heat and power (CHP) systems using a solid oxide fuel cell (SOFC) in cold regions. First, we evaluated the basic performance of the SOFC-CHP system. The AC electrical efficiency and heat recovery efficiency using the higher heating value (HHV) were 40.4% and 35.8%, respectively, and showed extremely high performance according to the specifications. Second, we carried out a proof-of-principle experiment that assumed standard examination modes and actual field conditions, and confirmed that the energy consumption was reduced compared to a conventional system. Numerical analyses were performed that showed the superiority of the SOFC-CHP system to other CHP systems, and the energy demands upon introducing this system.

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Natural energy use is important to reducing the energy consumption of buildings. However, there are advantages and disadvantages to using natural energy in traditional systems. Further reducing energy consumption with traditional systems is difficult. Therefore, we proposed a multi-source and multi-use heat pump (MMHP) to achieve higher efficiency than traditional systems. The MMHP system connects multiple heat sources such as solar heat, the ground, and air and multiple heat uses such as cooling, heating, and a hot water dispenser with a water loop. Each type of heat use side can utilize heat efficiently. However, there is a distinct lack of highly efficient hot water dispensers available. Therefore, we developed the instantaneous hot water dispenser based on a water source (IHWD WS) heat pump. In this study, we developed a prototype of the IHWD WS heat pump. The coefficient of performance of the IHWD WS heat pump was 5.2 in winter and 8.5 in summer. In addition, we developed a performance curve of the prototype. The performance curve of the prototype was modeled, and the model accuracy was confirmed to be within 4%.

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The Great East Japan Earthquake caused cases of non-structural components and falling equipments. This seismic damage is not only dangerous to humans but can also cause buildings to lose functionality. Thus seismic intensity measures are a pressing need. In this study, we focused on two features the hanger bolt of the supporting material and the unwinding pipe for a sprinkler system. Shaking table tests were performed. The experimental results for the unwinding pipe of a sprinkler, showed that one effective measure was keeping the unwinding pipe flexible and the main water supply firmly fixed. Tests on the seismic performance of a hanger bolt showed that the weight supported by the bolt can be considered as an important factor. Based on the average and cumulative rotation angle, the input acceleration increased as the hanger bolt diameter decreased

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