Abstract
A worldwide shortage of drinkable water has resulted from the rapid rise of industrialization and population, which has prompted researchers to find an alternative method to meet this requirement. Solar still are systems powered by solar energy that can provide drinkable water, however it has a low production issue. In this study a conventional solar still (CSS) and a modified solar still (MSS) have been tested in this experimental study. Copper water heating coil, an external condenser, and Nano-phase change material (PCM-Ag) have been employed to increase the productivity of the MSS. In three sets of experiments the performance of MSS and CSS were compared under identical meteorological conditions. The findings showed that, the productivity increase/thermal efficiency for MSS with heating coil, MSS with external condenser, and MSS with PCM-Ag layer are 76 %/45.4 %, 120 %/52 % and 111 %/50.7 %, respectively. So, employing PCM or external condenser increased the productivity of MSS with heating coil by about 35 % and 44 %, respectively. Economic analysis was also taken into account, and the costs of the distilled freshwater for the CSS, MSS-PCM, and MSS-EC 0.029, 0.024, and 0.022 $/l, respectively.
•Conventional solar still has been modified with copper heating coil.•The modified solar still showed 76 % higher productivity than conventional one.•External condenser and Nano-PCM have been employed with the modified solar still.•Adding external condenser enhanced the modified solar still productivity by 44 %.•Employing PCM increased the productivity of the modified solar still by 35 %.