Potential application of a novel integrated adsorption–absorption refrigeration system powered with solar energy in Australia

Abstract

• Thermal performance study of a solar integrated AD–AB cooling system is performed. • Two solar system layouts with and without storage tank are investigated. • A considerable high cooling energy produces at low-grade solar thermal energy. • An economic analysis is performed to evaluate the feasibility of the solar system. • A stable system energy performance is obtained under different climate conditions. This article presents a new effective utilization way of low-grade solar energy to produce cooling power with a novel integrated adsorption - absorption cooling system under climate conditions in Australia. In the integrated cooling system, the solution generation happens in the intermediate pressure, which is associated with the heat source temperature and can be adjusted according to the solution concentration and generation temperature. Two different solar system layouts with and without hot water storage tank are investigated. In the system without storage tank no cooling energy is generated at the beginning and ending cycle time and it reaches the maximum value of 16 kW around noon. While the maximum cooling capacity, 15 kW, is produced in the late afternoon between 14 h and 16 h along with higher cooling capacity at the beginning and ending cycle time in the system with storage tank. It is found that the average daily cooling capacity improve by 15% with better coefficient of performance by installing storage tank for a wide range of collecting area. Furthermore, the average daily coefficient of performance remains slightly stable at around 0.37 with expanding the solar collecting area. Results obtained from the economic analysis disclose that the lifecycle cost is minimised for the financially viable collector area of 34 m 2 . Moreover, the payback period of 10.46 years for the optimum collecting area indicates the high profitability of the solar energy application in the proposed cooling system in a 25-year project investment lifetime. The performance comparison among various solar systems indicates that the average daily specific cooling powers are as high as 106 and 121 Wkg −1 in the 1st and 2nd layouts respectively, which are achieved considerably greater than other systems operating at low driving hot water temperature of 60 °C. The low heat temperature required to run the proposed cooling system and the advantage of high solar radiation availability in Australia proves the high potentiality for operating the proposed system in most warm months.