Subjective experiments were conducted in order to investigate the effect of indoor humidity on subjective thermal comfort under the constant SET^* conditions. Two levels of SET^*, SET^*26℃ and SET^*28℃, were set. Four relative humidity conditions, 35%RH, 55%RH, 65%RH and 75%RH, were examined for each SET^*, adjusting the air temperature. Subjects were exposed in a climate chamber for 180 minutes. They were asked to walk up and down 12 steps every 10-minute during the first 90 minute, 20 steps every 5-minute during next 15 minutes, and then 12 steps every 10-minute again during the last 75 minutes. Effects of indoor humidity on subjectve thermal comfort, humidity sensation were moderate under the steady state. It would be because of higher temperature at lower humidity in order SET^* to be kept at constant for 4 humidity conditions. People felt the air was warmer and reported greater discomfort at high humidity when their metaboric rate was higher. Subjective dryness sensation was lower under the transient conditions with 1.6met of metabolic rate than steady state with 1.2met. It was observed that their skin moisture was significantly higher at high humidity even under the constant SET^* conditions.

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In hot environment, sweat sometimes drips down from the body without evaporating on the body surface. However, in case wearing clothing, a part of the sweat supposed to drip makes clothing wet and evaporates through wet clothing, that increases body cooling power. We introduce a rate of effective sweat increase. A series of experiments was conducted by using collage age students in a climate chamber and a value of 0.6 as the effective sweat increase rate was obtained by applying our human model for predicting mean skin temperature and sweating rate including dripping sweat. In this paper, we demonstrate that the mean skin temperatures predicted by our model agreed well with those derived from experiments.

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We analyzed the change in CO_2 emissions of a municipal waste and wastewater treatment infrastructure in on-site wastewater treatment equipment area, by introducing newly developed household on-site wastewater treatment equipment that were acceptable for disposer wastewater, and disposer wastewater treatment-systems for detached houses. The CO_2 emission reduction effect of the incineration process resulting from the introduction of the newly developed on-site the wastewater treatment process, and total CO_2 emissions decreased by 0.6% compared to previous levels. In the case of the introduction of disposer wastewater treatment-systems combined with conventional on-site wastewater treatment equipment, CO_2 emissions increased by 39% compared to previous levels. LCCO_2 resulting from the introduction of disposers in on-site wastewater treatment equipment area was 17% greater than the introduction in sewage treatment as a result of water-treatment efficiency, which may affect the treatment scale.

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The water thermal energy storage systems in the air-conditioning systems are installed in many buildings and their energy performance are greatly concerned. However, flow rates in the systems are unmeasured in some small systems because of expensive flow meters. Operation conditions of these systems can not be investigated, and appropriate operation conditions can not be achieved. The aim of this study is to investigate the operation conditions of the thermal energy storage systems. In this paper, a flow rate estimation method is presented. This method is using the heat balance in each divided tank and flow rates are estimated by using temperature data which are easy to be measured. Firstly, the accuracy of estimation method is confirmed by the generated data of system simulation without measurement error. Then the results of flow rate estimation by the measured data in real buildings are reported.

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It is important to maintain indoor air and sanitary environments in waiting lounges, office rooms and medical wards of medical facilities. However, Japan has neither environmental nor hygiene law for medical facilities. In this study, the way of the maintenance of sanitary environments in medical facilities was examined. This part reported the measurement results of air temperature, relative humidity, airflow rate velocity, CO, CO_2, PM and formaldehyde concentrations in waiting lounges, office rooms and medical wards of 16 medical facilities in winter and summer. As a result, relative humidity values in most part of the rooms in winter were lower than 40%Rh. The CO_2 concentrations in the waiting lounges that had a lot of people were remarkably high. It can be presumed that the capacities of the ventilating rate were insufficient.

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Generally speaking, as for heating load calculation, indoor heat which is released from OA instruments, human body, and lighting equipment during winter is taken no account in maximum heat load calculation method, because they act on the safety side for air-conditioning system. However, owing to increasing indoor heat and improving building insulation efficiency in recent years, heating load during winter begin to decrease. According to another report which investigates heating load in cold district, it tells us that every hour daytime heating load except starting time in the morning is almost 50% in comparison with the results which is calculated using maximum heat load calculation method. We can also know from this report that heating load tend to decrease even in the cold district. If we design heat source capacity using present design method in spite of these background as stated above, it could be overestimated and deteriorate its energy saving performance owing to frequent partial load operation. Therefore, from the point of improving energy saving performance for air-conditioning system in the cold district, it is important for us to design its heat source capacity appropriately. Aiming to suggest a new heat source design method for air-conditioning system in the cold district, we carried out investigation on heating load and cooling load in the designated office building. We have also practiced fundamental preheating test during winter with a purpose of reducing peak heating load, which occurs starting time in the morning and confirm its reproducibility of results of measurement and annually basis energy saving effect using general purpose simulation program HASP/ACLD/ACSS. In this report, results of these studies are presented. It was found that new heat source design method, which enable us to reduce heat source capacity in cold district in comparison with the one which is designed by present design method, could be available.

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