Experimental Investigation and Performance Analysis of a Mini-Type Solar Absorption Cooling System

A solar-powered absorption cooling system with the cooling capacity of 8 kW was designed and built. Lithium bromide-water was used as the working pair of the chiller. Solar collectors with an area of 96 m² were installed on the building roof The U-type evacuated tubular solar collectors with CPC (Combined Parabolic Concentrator) were employed as the driving heat source to supply hot water for the regeneration of the absorption chiller. A water storage tank with a volume of 3 m³ was used to store the hot water from the solar collectors. It worked as a buffer to reduce the influence of instability of solar energy. The experimental results showed that the average PMV and PPD values were 0.22 and 5.89, respectively. Taking the average values of PMV and PPD into consideration, the solar absorption air conditioning system could meet the indoor thermal environment with the comfort class of A. The electric power conservation was 43.5% by introducing energy stepped utilization in supply air handling unit. A Matlab program model was established based on the experimental system. The simulation results show that the solar radiation intensity has a greater impact on the solar powered absorption cooling system than the ambient temperature does. It is also shown that the indoor air temperature goes down while the solar radiation intensity increases from 10 MJ to 28 MJ. However, the indoor air temperature goes up when the ambient temperature increases from 25°C to 40°C.