Enhancing solar desalination efficiency: Performance analysis of coated hemi‐cylindrical solar stills

Abstract The intention of the present investigation was to experimentally enhance the effectiveness of hemi‐cylindrical solar stills (HCSS). The current article imparts an extensive energy and exergy analysis of both a typical SS and one with Chlorinated polyvinyl chloride (CPVC), N‐methyl‐2‐pyrrolidone (NMP) coated modified HCSS. This investigation is novel as it examines the coated HCSS that yields more water. The findings revealed that a rise of 15% in clean water production occurs after the coatings were applied to the HCSS. The conventional HCSS and coated HCSS have the highest yield productivity of 1.985 and 2.87 L/m 2 , respectively. An improvement in the distillate yield per day of 0.455 L/m 2 on 19th May 2025, 0.45 L/m 2 on 20th May 2025, 0.445 L/m 2 on 21st May 2025, 0.41 L/m 2 on 22nd May 2025, 0.51 L/m 2 on 23rd May 2025, 0.445 L/m 2 on 24th May 2025, for a 1.5 mm coated HCSS. 260 W of output power was obtained for conventional SS, while a coated HCSS achieved 297 W of output power. The conventional HCSS has energy and exergy efficacies of 7.2% and 0.7%, respectively, whereas the coated HCSS has energy and exergy efficacies of 27.4% and 4.2%.