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[en] A mini-type solar-powered absorption cooling system with a cooling capacity of 8 kW was designed. Lithium bromide-water was used as the working pairs of the chiller. Solar collectors with an area of 96 m2 were installed. A water storage tank with a volume of 3 m3 was used to store the hot water from the solar collectors. The experimental results showed that the average values of PMV (Predicted Mean Vote) and PPD (Predicted Percentage of Dissatisfied) of the test room were 0.22 and 5.89, respectively. Taking the average value of PMV and PPD into consideration, the solar cooling system could meet the indoor thermal comfort demand with the comfort level of A. The power consumption was reduced by 43.5% after introducing the stepped utilization of energy into the air handling unit. Meanwhile, a theoretical model was established based on Matlab to predict the variations of the system performance with ambient parameters. It is shown that the solar radiation intensity has a greater impact on the performance of the solar powered absorption cooling system compared with the ambient temperature. It is also shown that the indoor air temperature goes down with the increase of the solar radiation intensity as well as the decrease of the ambient temperature. -- Highlights: • The energy step utilization improved the performance of a solar cooling system. • Thermal environment of Class A was achieved by using radiant cooling. • Solar radiation intensity has prominent impact on the solar cooling system
[en] A constant temperature and humidity air-conditioning system driven by ground source heat pumps was designed and constructed in an archives building in Shanghai, China. The system consists of two water-to-water heat pumps and 280 boreholes with 80 m in depth. In order to keep the temperature and humidity constant, the operation mode that one heat pump ran in heating mode and the other one ran in cooling mode was deployed. According to the experimental results under typical winter weather condition of Shanghai, the average COP of the heat pump in heating mode was 5.2. The average temperature and relative humidity of the archives house were 22.8 deg. C and 52.5%, respectively. It was found that the operation mode we deployed could reduce the heat absorbed from the soil by 20%. Theoretical analysis showed that it was helpful for the earth energy conservation with one heat pump operated in cooling mode in winter. It was also shown that the decrease range of temperature of the soil in the middle of two boreholes would reduce with the increase of the distance between two boreholes. The distance between two boreholes is suggested to be 4-5 m in Shanghai.