Performance evaluation of solar absorption-compression cascade refrigeration system with an integrated air-cooled compression cycle

Abstract

Due to intermittent and uncertainty natures of solar energy, the conventional solar absorption-compression cascade refrigeration (SA-CCR) system cannot meet the all-weather cooling/heating demand when solar inputs are insufficient. In this work, a novel SA-CCR system with an integrated air-cooled vapor compression refrigeration (ACR) cycle is proposed. It is coupled of two subsystems: a solar-driven single-effect absorption refrigeration (SSAR) subsystem and an electricity-powered dual-source vapor compression refrigeration (EDCR) subsystem. The two subsystems are cascaded by one evaporative-condenser. The following improvements are achieved by the novel system: (i) the efficiency and the time of solar energy utilization are respectively improved and extended dramatically; (ii) the all-weather cooling/heating demand is met by coupling an ACR cycle to the EDCR subsystem. The proposed system is applied to a building located in Zhengzhou city to evaluate its cycle and economic performance. On a basis of different grade energy, i.e., thermal and mechanical energy, the novel SA-CCR system with an integrated air-cooled compression cycle is respectively compared with the conventional SSAR and ACR systems. The results show that the whole cooling season power (energy) consumption is reduced by 26.70% as compared to the conventional ACR system, and that the proposed system has the better economic performance than the two conventional SA-CCR systems.