Solar Adsorption Cooling: Innovations in Adsorbent Materials and Cycle Design

Abstract

This review paper covers progressive developments in solar adsorption cooling technology with reference to new adsorbent materials and thermal cycle patterns for upgrading the performance of the system. An alternative for conventional cooling technologies, Solar adsorption cooling technology harnesses the heat from the sun to power the adsorption process, instead of electricity and destructive refrigerants. The first part of the review provides brief background information about the operation of solar adsorption cooling systems and the role of solar collectors as well as adsorbent materials in the process. Based on such categories the paper outlines the advancements in adsorbent materials including the metal-organic frameworks (MOFs), silica gel, activated carbon and zeolites that have enhanced efficiency, capacity and stability that work well under various conditions. Moreover, the review looks into the design improvements in adsorption cycles with the focus on new trends in adsorption in order to enhance the performances, increase the coefficient of performance (COP) and decrease the running costs. When solar thermal systems are combined with the adsorption technologies, the systems can provide cooling in an efficient way, and are ideal for areas that receive high levels of radiation. Furthermore, the externalities of these systems are rigorously examined to highlight their abilities to enable low carbon and fossil-free solutions. The paper also discusses the multipurpose use of solar adsorption cooling for residential air conditioning to industrial refrigeration which has been demonstrated in cases. Last, the difficulties associated with the choice of the working fluid, the system configuration, and the expansion of this technology are presented, after which the possible further studies that could improve the performance of the solar adsorption cooling systems and therefore guide their application are investigated.