Performance Analysis of a Solar Cascaded Absorption Cooling System (SCAC) Using a Performance-Enhanced Parabolic Trough Collector

Abstract

This paper proposes an innovative approach to improve the performance of solar cooling systems by utilizing a cascaded absorption cooling (CAC) system. The paper also examines the viability of coupling an NH3-H2O absorption system with an H2O-LiBr absorption system to simultaneously satisfy both a refrigeration load and an air-conditioning load. Results of this analysis shows that the CAC system uses 7.1% less thermal energy than the sum of the energies used by the ammonia absorption system and the LiBr absorption system if they were to operate separately to meet the same cooling load. In addition, the paper investigates the impact of a performance-enhanced parabolic trough collector (PEPTC) on the thermal and exergetic efficiencies of the solar cooling system. By employing a PEPTC, the area required for the solar field in a given solar cooling system will be reduced by 14% compared to the area required by a conventional PTC. Combining the CAC system with the PEPTC results in a 22% increase in the overall efficiency of a cooling plant compared to a conventional PTC coupled with an ammonia system and a LiBr system in the same plant. In summary, it is suggested that the simultaneous utilization of the proposed CAC system and the PEPTC can considerably improve the efficiency of solar cooling systems. Doing so, will lead to sustainable cooling alternatives.