Recent Advancements in Evacuated Tube Solar Water Heaters: A Critical Review of the Integration of Phase Change Materials and Nanofluids with ETCs

Evacuated tube solar water heaters are gaining more attention in the present market scenario as compared to conventional collectors. Such collectors versatile because no tracking is required and operating temperature range also broad. Comparatively, it cost-effective may attain higher thermal efficiency. However, like other collectors, continuous energy supply sometimes hampered by intermittent nature of radiation. This problem can be partially resolved using phase change materials (PCM) evacuated collector (ETC). PCMs store during sunshine hours, which released when not available. In literature, several studies available pertaining use ETC-based heaters. The literature indicates that integration with ETCs has merits. Nevertheless, systematic, comprehensive review papers dedicated such integrated storage systems ETC Hence, objective this work compile relevant experimental, numerical, theoretical works reported literature. paper broadly reviews recent design modifications, PCM different kinds heaters, their life cycle assessment. Furthermore, application nanoparticles discussed, finally, a roadmap for system provided.