Enhancing solar still efficiency using different basin water additives

Incorporating various materials into the basin water of solar stills can significantly enhance their efficiency, offering a sustainable solution for freshwater production in remote and arid regions. This study addresses a critical gap in previous research by systematically evaluating both conventional and unconventional materials, such as iron filings, wick cotton, Burlap, and paraffin wax, within a single solar still under identical environmental conditions. Unlike prior studies focusing on single material or separate experiments, this work provides a reasonable comparative analysis, highlighting the effects of different additives on solar still performance. This study investigates the effects of various materials on solar still performance under summer conditions in Kafrelsheikh, Egypt. A conventional solar still (CSS) unit was evaluated alongside modified configurations incorporating these materials, with performance assessed in terms of water yield, basin and glass temperatures, and energy efficiency. Results revealed that CuO nanoparticles outperformed others, achieving enhancement ratios of 141%, 128%, and 132% for basin water temperature, glass temperature, and freshwater productivity, respectively. Wick cotton and Burlap also showed notable improvements, with hourly productivity enhancement ratios of 126% and 123%, respectively. Cumulative freshwater yields were highest for CuO at 4.13 L/m², followed by Al₂O₃ (3.91 L/m²), wick cotton (3.83 L/m²), Burlap (3.72 L/m²), PCM (3.62 L/m²), and iron filings (3.54 L/m²). Energy efficiency peaked at 1:00 p.m., with CuO achieving a 137% enhancement ratio over CSS. These findings revealed that CuO nanoparticles are the most effective additive for optimizing solar still performance, offering valuable insights for advancing sustainable water production and energy efficiency. • Various materials in solar stills were studied to boost efficiency for freshwater production. • Materials tested include iron filings, wick cotton, Burlap, and paraffin wax. • CuO nanoparticles achieved the highest basin, glass temperatures, and productivity. • Cumulative yield highest with CuO (4.13 L/m²), followed by Al₂O₃ and others. • Energy efficiency peaked at 1 PM; CuO showed 137% enhancement over the conventional one.