Heating systems in group houses (Wohnsiedlung) and a house designed and used by the prominent German architect Bruno Taut were investigated. The utilization of radiant heating systems in the 1920s Germany became apparent. In the group houses, cast iron radiators and ceramic stoves were used, and a heating system using radiators with gravitational circulation system was being used in his house. It is apparent that warm water radiator heating system using gravitational circulation system was in common use in houses of this era. In the group houses, natural ventilation utilizing the chimney effect through the steep stairways was incorporated to provide comfort in the mild summers of Berlin. These houses, now renovated, are still in use today, utilizing pump circulated central warm water radiator heating systems.

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In order to assess the thermal environment improvement effect of an evaporative cooling system that is used to cool buildings by wetting their photocatalyst-coated external surfaces, the authors have proposed a thermal modeling to predict the temperature of the photocatalyst-coated surface with water, and integrated the calculation algorithm into the thermal environment simulation tool previously developed by the authors' group. This paper presents a numerical analysis of the system's cooling effect for various applied urban districts in the downtown of Tokyo, based on the simulation results using the above-mentioned simulation tool. Through simulations, it was found that the heat island reduction effect of the cooling system differs from land use and building types, etc. For clarifying the relationships between the thermal environment improvement effect and related factors, case studies were carried out to quantify the impacts of construction materials of the watered wall surfaces and outdoor configurations on the urban/built thermal environment in terms of the surface temperature, the heat island potential (HIP), evaporation, indoor air temperature and building cooling load. As a result, the simulation results show that the temperature difference between the watered surfaces with different construction materials is small, whereas evaporation and building cooling load reduction greatly differ from the wall construction materials. The temperature of the shaded surface with water can be reduced lower than outdoor air temperature in the daytime.

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A variable speed control of the compressor is known as a key technology of high performance heat pumps. In recent years, the inverter control technology for centrifugal chillers has been improving spectacularly. The inverter centrifugal chiller is a heat pump which can be used in a wide range of temperature at a high efficiency of performance. This is an advantage of the aerodynamic characteristics of the centrifugal compressor. This characteristic suggests there is a good chance of high energy saving of a heat source system for air-conditioning, so we are going to report new design techniques and the control method for an appropriate air-conditioning heat source system for business use. Therefore, it is necessary to carry out highly accurate simulations with the performance prediction model of the inverter centrifugal chiller and the performance prediction model of the cooling tower. The purpose of this first report is to clarify the performance of the inverter centrifugal chiller using actual measured data taking into account uncertainness of each value. Not only the rating point performance but also partial load points performance are evaluated. Each efficiency calculated from measured values was fairly satisfactory in large area within comparison to thermodynamic theoretical efficiencies. Furthermore, by using characteristic of the aerodynamics machine of the centrifugal compressor, we have been able to identify the performance characteristic of the inverter centrifugal chiller in a domain measured values closed to theoretical efficiencies. Especially, an improving cooling tower performance suggests a big energy saving potential of the heat source system. For air-conditioning system use, seasonal performances were fundamental to the evaluation of energy saving. But the consideration of uncertainness of seasonal performance is not enough, so by using measured data which evaluate uncertainness, we can describe appropriate observations about the seasonal performance.

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The monthly energy consumption in the residential sector of seven cities in Kansai and Shikoku regions were estimated by using statistical data on family income and expenditures and retail price surveys provided by the statistical bureau of Japan. The estimated gas or electricity consumption in Osaka, Wakayama, and Kochi was compared with the statistical data provided by the corresponding local government units to validate the estimation procedure. After the validation, the authors investigated the influence of air temperature on the estimated and validated energy consumption. Based on the regression analyses, the monthly electricity consumption per household in each is expressed as a quadratic function or a couple of linear functions of air temperature. Total gas consumption and kerosene consumption are expressed as linear and quadratic functions respectively.

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In 2005 we developed "Sub-cooling System with Multiple packaged air conditioning units". This system saves energy consumption of air-cooled air conditioner by cooling water, such as established cooling tower, well water and so on. In the past two years, we were verifying rigorously the effect of energy saving by several field tests. As a result, now we can estimate the effect of this system so exactly. For example, if a building for offices which has an area of 10,000 square meters in Tokyo introduce this system, electrical power consumption for cooler should decrease by 12% as compared with normal system. We explain the background and outline of the development and show the outline and result of several field tests.

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Raw data sets of inhabitants' behavior schedule for24 attributes based on the 2005 survey by NHK were generated through the method the authors reported previously. There are generated two data sets; one is through the usual method, another is generated through the adjusted method, in which each standard deviation of ongoing minutes of a certain behavior has less discrepancy from the original NHK data. Statistical comparisons between those two generated data sets and original one imply reasonable accuracies. The generated data sets are available by downloading from the authors web site.

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By using STAR-CCM+^<TM> and polyhedral meshes, simulations of internal flows were carried out. In the simulations of miter bends, adequate polyhedral meshes gave accurate values of loss coefficients for θ_b≦90°. However, there was a large gap between the simulated and measured loss coefficients for θ_b>90°. In the simulations of combining flows, adequate polyhedral meshes also gave accurate values of loss coefficients in sub tube. However, there was a gap between the simulated and measured loss coefficients in the main tube.

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