In the New SUBARU facility, we have made a comprehensive investigation on the energy reduction and temperature-stabilization in regard to the air-conditioner and insulating structure of experimental building to cope with the hot summer and cold winter, which is becoming serious in recent years. According to the statistics of yearly consumption of electric power and water and its cost, the electric power cost of air-conditioner is about 10 % of the total, which roughly provides a limit of the investment for the present purpose. A computer program, developed to calculate the temperature distribution in the building, successfully provided numerical results, which approximately agrees with measured temperatures. There are four candidates for the energy reduction of the building in hot summer;1) introduction of out-door air,2) high reflection paint on the roof,3) high reflection sheet on the ceiling,4) water spreading on the roof. Appling the program to the candidates, we found that the water spreading is the most effective, economic and easy, (but with a minor problem remained). At the same time, we can expect a drastic improvement of the temperature stabilization. Similarly, discussions are extended to the winter problem.
