Performance of a single slope solar still using different porous absorbing materials: an experimental approach

Desalination is a critical process to address water scarcity in arid regions worldwide, and solar stills provide an economical solution despite their productivity limitations. This study aimed to enhance the performance and productivity of solar stills by constructing two stills with different natural and artificial absorbing materials such as black luffa, luffa, fine steel wool, and steel wool pads. The solar stills were tested in Egypt under comparable weather conditions, and their productivity, solar intensity, wind velocity, and temperature were measured to determine their thermal efficiency and exergo-economic analysis. Results showed that the choice of absorbing material significantly impacted solar still productivity, with steel wool pads achieving the highest yield of 4.384 l/m². Moreover, steel wool pads also exhibited the highest thermal efficiency at 32.74%. The cost per liter (CPL) was the lowest with steel wool pads at 0.0034 $/l/m². Finally, the payback period and exergo-economic analysis demonstrated that incorporating steel wool pads was the most promising modification for enhancing solar still performance compared to other modifications.