In this study, a desiccant outdoor air-conditioning system that uses high-temperature chilled water (approximately 20℃) and low-temperature hot water (approximately 55℃) produced by a high-efficiency heat pump, and hot air produced by solar heat collectors, was proposed. This system treats the total heat load of outdoor air and indoor latent heat load in commercial buildings. We constructed a prototype of this system and evaluated the coefficient of performance (COP) of the entire desiccant air-conditioning system by using the measured values of electric energy consumption and treated enthalpy between the outdoor air and supply air. In addition, we estimated the period energy consumption during summer. The following information was obtained. 1) In high-load conditions, the system COP was between 2.91 and 3.27 without solar heat and 3.84 with solar heat. The target system COP2 was achieved. 2) We confirmed that more than 78% of the energy for regenerating the desiccant was provided by solar heat when solar radiation was greater than approximately 800W/m^2, which indicates a high rate of solar heat use. 3) The COP can be further improved by reducing the transport power under low-load conditions. 4) The energy consumption during the summer season was effectively reduced by 13.6% with the use of solar heat.

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This paper reports on the investigation of the actual conditions of the ESCO business that the Osaka Prefectural Government handled. The accuracy of the actual base-line correction formula was compared with the regression formula and LCEM's simulation and the practical effectiveness of the base-line correction formula was verified. The actual base-line correction formula was found to be as accurate as the regression formula and LCEM's simulation which were as useful as the base-line correction formula.

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Energy saving strategies for air cooling include methods that utilize the latent heat of water such as local cooling by dry mist, roof cooling by spray, and greening of building. In this report, the air temperature for cooling by using the latent heat from a moisturized test cloth on some cooling plates in a duct was investigated. The specific retention and evaporation rate of the test cloth were 130mass% and 3.21g/(m^2・min), respectively. The heat of cooling, which is the air temperature difference between upstream and downstream of cooling plates, was measured for velocities ranging from 0.5 to 4m/s, air temperatures ranging from 24 to 31℃ and relative humilities ranging from 50 to 80%. It was observed that the heat of cooling increases with increasing air temperature, air velocity, the number of plates and the length of plate, and decreases with decreasing air humidity.

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The coefficient of performance (COP) of room air conditioners greatly depends on the use conditions and its actual values deviate from the catalogue values. To solve this problem, we developed a heat source characteristic model for accurately estimating the power consumption and COP of air conditioners under arbitrary operating conditions. In this study, we improved the developed heat characteristic model to estimate the amount of heat treated and the power consumption of air conditioners in an unsteady state and we experimentally examined the validity of the improved model. The following was accomplished. 1) The conventional heat source characteristic model for air conditioners was improved to estimate the power consumption of air conditioners in the unsteady state, for example, under arbitrary variable conditions of temperature, humidity, and heat load inside and outside. 2) The maximum cooling capacity was measured at different temperatures of air taken in by the indoor and outdoor units of air conditioners in an adiabatic room that blocks the exchange of heat between indoors and outdoors. The difference between the experimental and calculated values fell within approximately ±20%. 3) A stepwise heat load that changes with time was provided to an adiabatic room that blocks the exchange of heat between indoors and outdoors, and operating tests were performed to examine the power consumption during cooling and heating. The power consumption measured experimentally was compared with that estimated using the heat source characteristic model incorporated into the simulation program. When the temperatures of air taken in by the indoor and outdoor units of air conditioners, heat load, and the interval of stepwise heat load applications were changed, the difference between the measured and calculated average power consumption in each test fell within approximately ±20%. The power consumption of air conditioners can be estimated by the improved model with this error range.

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