Enhanced solar still operation using a copper coil heat exchanger and phase change material integration

This research proposes a novel design for a solar still that aims to enhance its efficiency and productivity. By strategically placing a copper coil on the back wall of the traditional distiller, the system leverages the coil's dual functions as a heat exchanger and condenser. To further optimize performance, a phase change material (PCM) is integrated into the design. The PCM, strategically positioned beneath the absorber, stores excess energy during periods of high solar radiation, helping to regulate the temperature of the glass and maintain optimal operating conditions. The cumulative productivity of MSS with coil 1 (5160 ml/m²) was 75 % over CSS (2950 ml/m²). Also, the MSS's cumulative productivity with heating coils 1 and 2 (5950 ml/m²) was 95 % over CSS (3050 ml/m²). Besides, the MSS-PCM output (7100 ml/m²) is 131 % over CSS (3100 ml/m²). Also, the yield enhancement/energy efficacy for MSS with coil 1, coils 1 and 2, and PCM-Ag were 75 %/46.2 %, 95 %/49 %, and 131 %/54.6 %, severally. Moreover, the resulting water expenses are 0.029 and 0.017 $/l for CSS and MSS-PCM, severally. Also, the exergy efficacy was approximately 2.7 %, 2.9 %, and 3.26 % for MSS + coil-1, MSS + coils and MSS + coils + with PCM, accordingly. The environmental impact, quantified as annual CO₂ emissions, was determined to be 6.833 tons for the CSS and 14.5 tons for the MCSS. Similarly, the enviroeconomic parameter was calculated to be 99 and 210 per year for the CSS and MCSS, respectively.