Desiccant cooling system has been suggested to be a suitable system to improve IAQ (Indoor Air Quality) by its superior performance of humidity control, and decrease the health risk generated by mold growth. However, this system has a defect of its lower energy efficiency, so combining with power generation system, such as co-generation system, is commonly used to improve its energy efficiency. The purpose of this research is to realize a non-condensing environment by developing a non-condensing air-conditioning system (a HVAC system without condensation both in the indoor environment and inside the air-cooling system with high energy efficiency). In this paper, the authors studied the possibility and methods of combining desiccant cooling system with CO_2 heat pump that can improve its energy efficiency and provide steady heat source. The authors also studied the adaptability of the system under mid-summer climate, and evaluate the performance of thermal comfort, IAQ (Indoor Air Quality) and energy efficiency by experimental data and performance data of CO_2 heat-pump. In this paper, the actual situation and countermeasure of indoor microorganism pollution was reviewed, and a new type of desiccant air-conditioning system combined CO_2 heat pump is proposed. In this system, heat generated from condenser and gas-cooler of CO_2 heat pump are used to be the heat source of desiccant air-conditioning system. The authors also studied the performance of system by assume the CO2 heat pump has combined with desiccant air-conditioning system. The result of calculation shows the system COP to near 2, and is a significant improvement of energy efficiency by comparing with a normal desiccant air-conditioning system.

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In this study, a personal air-conditioning system considering the human thermal adaptation is analyzed. Although a lot of studies of conventional individual personal air-conditioning system indicate that it provides thermal comfort, it doesn't necessary decrease running energy. The purpose of our study is to develop personal air-conditioning system considering both thermal comfort and energy conservation. In this paper, we define 'response time' as personal air-conditioning system eases thermal stimulus due to change of activity, and examine it by subjective experiment. As the result, thermal discomfort due to walking exercise is eased within 5 to 10 minutes by the personal air-conditioning system. But, after further 2-3 minutes, subjects feel discomfort because of dry eyes or cold.

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In the series of the report, we proposed to lower a temperature of water surface in a open space such as an atrium. The contents of the past three reports were the experimental results of heat and vapor transfer on the running water in the case of the pond and fall, and the experimental results based numerical model of a heat and vapor transfer between air and running water. And what we have to do next is to make some simulation method for investigating the many-sided effects of the cool running water in a open space. In this report, we make the CFD analysis by the k-e model adding the boundary condition of the experimental results based numerical model. It is concluded from the results of the numerical analysis that: 1) The results of the CFD analysis are similar to the results of measurement nearby the water surface. 2) In the case of the distribution of air velocity, the results of the CFD analysis are not similar to the results of measurement in upper space. The reason of the difference is not clear but may be caused by the boundary condition that doesn't calculate in the CFD analysis such as a turbulent energy caused by a free surface water. 3) The distribution of air velocity, temperature, relative humidity that have strong relationship each other are influenced by changing water surface temperature. Particularly, the vortex in the lower space that is produced by cold water influences the distribution of temperature and relative humidity. 4) The distribution of relative humidity is influenced by whether the water temperature is under the condition of evaporation or the water temperature is under the condition of condensation. 5) The setting of water temperature will be optimized by calculating the air-conditioning design, the comfort and the energy efficiency, if there are the useful simulation methods.

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The purpose of this study is to establish a simple evaluation method of seasonal load by taking in outdoor air. So, this report shows the simple method of estimating heat load by mechanical ventilation and hybrid ventilation on office building. Expanded Degree Day was used to calculate building's heat load. The method was studied by re-expanding it. In this report, mechanical ventilation is the method for taking in outdoor air by using only a fan without using a heat source equipment. Hybrid ventilation is natural ventilation with a use of mechanical ventilation as an auxiliary ventilation. When Expanded Degree Day was used, quantity of outdoor air intake is controlled each day. Practically, the quantity is controlled at intervals 0.5-1 hour. So, its validity was examined. We can see close correlation between outdoor air load calculated at intervals of an hour and that calculated at intervals of a day. But the inclination of the regression line wasn't nearly equal 1. It can minimize this error by multiplying correction coefficient. Therefore, it is valid to calculate outdoor air load at intervals of a day. Maximum seasonal load is required to calculate maximum quantity of supply air. Overall heat transfer coefficient which is used in this calculation is able to be calculated by reference temperature. This makes it possible to evaluate air load by mechanical ventilation simply. Evaluation method of the load by natural ventilation was reported in previous paper, and the method of it by mechanical ventilation was above-mentioned. These two methods make it possible to evaluate outdoor air load by hybrid ventilation simply. If above results are collected each area, direction, reference temperature and the ratio of solar transmittance to overall heat coefficient in advance, it makes possible to estimate seasonal load simply including effects of mechanical ventilation and hybrid ventilation.

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A dataset of myriad and time-varying inhabitants' behavior schedules having 15-minute time resolution, generated by the authors in the previous study, is validated through a comparison analysis. Comparing between a time series of actual utility demand and estimated demand based on the generated schedule data for two residential buildings indicates that the generated data and its algorithm, described by the authors, have an appropriate robustness.

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For noise reduction on a vacuumed regenerative water heater, it is necessary to heat up the boiler water keeping the degree of subcooling within a low range. To keep this condition, the proposed method is to settle the auxiliary cover around the heater, which has the function manipulating the flow rate of boiler water automatically. Using this auxiliary cover, the low degree of subcooling can be accomplished at the early stage of heating. Furthermore, by making the heat flux low at the early stage, it could be confirmed that the noise level can be reduced by 13dB and the proposed method is efficient for noise reduction on this type of water heater.

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