As for proper operation and the retrofit that aims at the energy saving, the effect of controlling the energy consumed is large from the standpoint of the life cycle in the HVAC system. Recently, use in practical is not yet promoted easily though the system simulation begins to spread as one of the tools that support these. This study showed the method of using the HVAC system simulation on the assumption of the use of LCEM tool for the energy management when actual air-conditioning equipment was repaired. And, a quantitative evaluation of the repair proposal system was enabled by energy simulating.

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The purpose of the study is to establish a database on building equipment design and building simulations for the Chinese locations. In Part 2, solar radiation was estimated using method developed by the authors. The preciseness of this method was verified with observational data. Hourly radiation with TAC 2.5% was calculated, which was defined as solar radiation for cooling design. The hourly change ratio of the design radiation was calculated and this ratio was estimated with sin(h_i) ratio. More over, Direct and diffuse radiations for cooling design were also approximated with sin(h_i) ratio and the errors by the approximation were less than 6.0% in the period of 10:00-16:00.

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To study the effects of cool airflow on sleep, human subject experiments were conducted on 10 healthy young men. The desired environmental conditions were attained by using (i) a normal air-conditioner fastened to the wall in one evaluation room and (ii) a new ceiling air-conditioner in another room. The new ceiling air-conditioner exhaust dispersed airflow from a 2-piece ceiling panel (1800×900mm) covered with a 3-dimensional knit fabric, such that the airflow from the air-conditioners was not directly perceived. The mean air temperature, relative humidity, mean radiant temperature, and air velocity in the evaluation rooms were 26.4℃, 58%, 26.3℃, and 0.14m/s, respectively, with the normal air-conditioner and 26.4℃, 53%, 26.1℃, and 0.04m/s, respectively, with the ceiling air-conditioner. The PMV (predicted mean vote) was -0.3 (0.7met, 1.15clo) in both the evaluation rooms. The maximum air velocity above the bed in the evaluation rooms and the frequency of airflow were 1.1m/s and 28 times per night, respectively, with the normal air-conditioner and 0.3m/s and 11 times per night, respectively, with the ceiling air-conditioner. The comfort sensation and the total duration of each sleep stage did not differ significantly with the normal and the ceiling air-conditioners. However, the subjects in the room with the normal air-conditioner felt a stronger draft and reported being a little colder. The skin temperature on the forehead, arm and hand that were not covered with the bedding clothes decreased due to cool airflow in the room with the normal air-conditioner. The number of waking, body movements, and the increase in heart rate were significantly lower with the ceiling air-conditioner than with the normal air-conditioner. The cool airflow produced by the normal air-conditioner was considered to disturb the sleep. Our results suggested that the new ceiling air-conditioner secured better sleep.

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Increase of fuel cost of a heater used to heat a green house by sudden rise of price of crude petroleum becomes large problems in agricultural sector. And, the green house heater discharges the exhaust gas of the high temperature. It is significant to use the thermal energy (waste heat) of this exhaust gas by some methods effectively in the viewpoint of energy saving, saving resource, and stable supply of farm products. In this study, we examined the exhaust heat recovery system made by using the U-type thermosyphon. As a result, we clarified the utility of the waste heat recovery by the thermosyphon.

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By applying Total Utility Demand Prediction System (TUD-PS), authors built, to consider variation of inhabitants' behavior schedules, a series of investigations concerned on seasonal and maximum cooling/heating loads assuming a single dwelling in a residential building is reported. Several discussion points of how influential if inhabitants' threshold of HVAC turning on/off on thermal loads, cooling-off-timer setting, and discrepancy of considering/ignoring inhabitants' behavior variation are presented.

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