The purpose of this study is to clarify the actual conditions of energy consumption and the energy consumption of HVAC systems in the university campus with various HVAC systems. Therefore I collected the information of buildings and facilities in the TUT campus and energy consumption data of the past three years from 2003 and analyzed them. The annual primary energy consumption of TUT was about the same for three years, and it was 1530-1600MJ/(m^2・year) that were slightly bigger than that the university mean of bygones documents. The annual primary energy consumption in the building group where the lecture and a study were performed was 1000-2000MJ/(m^2・year), and the experiment building group was 2500-3500MJ/(m^2・year). The rate of annual energy consumption for HVAC systems was 34-36%, and it was increased 1% year by year. It found that the annual primary energy consumption for HVAC systems increases in order of the experiment institution, the lecture and research facility, language study center and library institution, the dwelling.

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This study examined the best form of the solar chimney for the natural ventilation by the scale down experiment and CFD simulation. As a result, in case of the horizontal cross section of the chimney smaller than 8m^2, the ventilation rate has increased when the horizontal cross section of the chimney increases. In case of the horizontal cross section 8m^2 or more, the ventilation hasn't increased when the horizontal cross section increases. And ventilation rate has hardly increased when the exhaust outlet is more than 5〜10m^2. Also, in case of the horizontal cross section of the chimney smaller than 8m^2, the ventilation rate has hardly increased when the cross-section ratio of the exhaust outlet to the horizontal cross sections is 1.2〜2. In case of the horizontal cross section 8m^2 or more, the ventilation rate has hardly increased when the cross-section ratio is 0.7〜1.2. And the aspect ratio 1:4 has shown maximum ventilation rate in case of 8m^2 of the chimney horizontal cross section. From these results, it found that the best form of solar chimney is 8m^2 of the horizontal cross section, 10m^2 of the exhaust outlet, 1.2 of the cross-section ratio and 1:4 of the aspect ratio.

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In large-scale food factories, sanitation control of microorganisms are strictly managed by HACCP. These factories require huge amount of energy, both in manufacturing processes and in ventilation system. Especially in the viewpoint of energy consumption in factories, load of ventilation system is relatively large, therefore, it is important to reduce the ventilation load. In order to improve productivity, indoor environment should be comfortable, and fatigue of workers should be minimized. Displacement ventilation system can give a good solution to such situation. In this paper, thermal environment and ventilation flow rate of a large-scale food factory with displacement ventilation system were investigated. Field measurements were carried out in summer and moderate seasons when manufacture equipments were operating. The simulated results based on the measured data showed that air flow rate could be reduced and thermal environment was kept in good condition.

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