Application of advanced energy storage materials in direct solar desalination: A state of art review

Storage of the thermal energy of solar intensity has a significant effect on the efficiency of desalination systems at nighttime, when solar intensity is not available. Solar energy provides the potential to facilitate the freshwater needs of small communities, where access to potable water is commonly limited. However, freshwater generation formation via solar stills remains low when compared to other desalination methods. Hence, multiple innovative materials for efficient water production by solar stills have been invetsigated in the literature, where this is addressed on a wide scale in this comprehensive review. This includes a focus on innovative materials including nanomaterials, nanofluids, nanoparticles-based phase change materials (PCMs), composite PCMs, PCMs with porous materials and PCMs with heat pipes. The review's outcomes identify that advanced energy storage materials substantially influence the enhancement of solar still productivity as compared to conventional solar stills. The results indicate that the application of thermosyphon heat pipes with PCM more than doubles the performance of solar still water productivity. The productivity of solar desalination can also be improved by utilizing PCM/porous materials, with results indicating solar still water productivity to be enhanced by between 40 and 70%. A cost analysis as well as an environmental evaluation of PCM-based solar desalination is also compiled in this review. A summary of the current status, leading groups, journals, and countries related to advanced energy storage materials in solar desalination is presented. Lastly, recommendations related to advanced energy storage materials in solar desalination are noted, assisting researchers to explore efficient water treatment methods.