An experimental investigation on the performance of single slope passive solar still for water desalination

In this study, a passive-type single-slope solar desalination system using solar energy for domestic applications was designed, fabricated, and tested for its performance. The effects of various factors such as ambient conditions, temperatures at various locations on the solar still, and air movement were considered in this study. An average cumulative productivity of 6 liters/m2 was obtained with a maximum of 6 to 7 liters/m2 in a few days. The quality of freshwater yield was good enough, with an average pH of 6 and TDS of 171 ppm. Maximum energy efficiency range between 12 to 14% was reasonably good for a solar still without any solar concentrators or enhancement techniques being incorporated in the still. Exergy efficiency ranged between 0.2% and 0.6% with a steep rise at 13 h and a drastic fall at 14 h. Productivity increased by 75 to 100% during 12 h and 13 h, whereas after 13 h, the rise in productivity was reduced to approximately 30 to 40%, which complemented the results of energy and exergy efficiencies.