Performance analysis of hemispherical distiller for different basin materials with mirrors and energy storage material

A multitude of studies exist on solar desalination systems, particularly focusing on innovative designs for covers and absorber materials to enhance freshwater production. Given the larger exposure area for evaporation and condensation, hemispherical solar stills have become widely utilized. This study primarily centers on improving freshwater yield by incorporating reflective mirrors and absorber materials made of zinc and copper into the hemispherical solar still. The thermal performance is evaluated and compared with a hemispherical solar still lacking these modifications. In addition, sand grains are introduced to the absorber as a means of energy storage. Experimental results demonstrate that the concurrent use of copper as a basin material with reflective mirrors and sand grains as energy storage significantly enhances freshwater production from the hemispherical solar still. The findings reveal an improvement in freshwater yield by up to 156% compared to a conventional hemispherical still. The conventional and modified hemispherical solar stills, with the combined effects of energy storage through sand grains, absorber plate, and reflective mirrors, exhibit a maximum accumulated yield of approximately 4.65 and 11.9 L/m2, respectively. The present findings affirm the importance of the proposed modifications to the hemispherical solar still.