Evolution of solar driven desiccant systems for energy-efficient air conditioning: A review

Abstract

Desiccant air conditioning systems promise to be a cost-effective, low-grade energy-driven, sustainable system demonstrating huge potential as an alternate method for indoor thermal comfort. The heat and mass transfer performance of a desiccant system depends on the thermo-physical properties of the desiccant materials and the efficiency of the dehumidifier and regenerator. The highest amount of energy consumption is during regeneration. This paper presents feedback on the experimental research on different desiccant systems and their integration with external systems as an energy-saving approach. The review focuses on state-of-the-art desiccant materials, solid and liquid desiccant systems, hybrid systems, and methods of solar-driven regeneration. The details of different dehumidifier/ regenerator components have been presented. Finally, a comprehensive summary has been provided for future research and developments. The review reveals that desiccant composites are economically more viable desiccant materials due to their flexibility to tailor the properties by basic methods. Novel hybridization methods have been proposed that would considerably reduce energy consumption as well as provide long-term stable dehumidification and regeneration performance. Major challenges lie in the practical verification of many of the proposed techniques.