Critical review on thermal performance enhancement techniques for flat plate solar collectors

Supply of energy against continuous increase in energy demand is a great challenge for the present time. This has compelled the researchers to develop energy-efficient and performance-enhanced devices. Solar energy, being the capable source to supply the clean energy can be harvested with the help of flat plate solar collectors (FPSCs). In order to enhance the thermal performance of FPSC researchers have considered various aspects, for example, design modification, heat transfer fluid having enhanced thermophysical properties, use of nanofluids, reduction in heat loss, use of enhancement devices, use of phase change materials and porous materials. The present article describes in detail these methods and compares the results obtained by the respective researches. Experimental as well as numerical works have also been presented. A comprehensive review for the thermal performance enhancement techniques used in FPSC has been presented. The objective of this review is to provide a valuable framework for evaluating and comparing different techniques for enhancing FPSC performance. The review aims to help identify the most appropriate approach and gaps in current research and proposes potential areas for future enhancements, which is expected to assist researchers.