Enhancement of solar still performance via wet wick, different aspect ratios, cover cooling, and reflectors

Abstract

The present study presents an enhancement in wick solar stills performance depending on using different aspect ratios with the same project area and wick materials, glass cover cooling, and external reflectors after practical knowledge of the best wick material type and dimensions. The proposed three stills (A), (B), and (C) have evaporation area dimensions of 1 × 0.85, 1.5 × 0.57, and 2 × 0.425 m2, with an aspect ratio of 1.18, 2.63, and 4.71, respectively. The results revealed that the solar still with medium dimensions set has the best performance. Also, adding a top and bottom reflector to type (B) solar still with cotton cloth wicks increased the freshwater productivity and energy efficiency by 37.99 and 39.96%, respectively, compared to type (A) solar still with cotton cloth wicks. Moreover, the cost of one liter of freshwater distillate was decreased by 1.82%. Applying glass cover cooling on type (B) solar still with cotton cloth wicks increased the freshwater productivity and energy efficiency by 30.59 and 33.13%, respectively, compared to type (A) solar still with cotton cloth wicks. Furthermore, we have a decrement in the cost of one liter of freshwater distillate by 7.69%. Moreover, adding reflectors and cover cooling together to wick solar still increased the freshwater productivity and energy efficiency by 52.36 and 58.5%, respectively. On the other hand, the cost per liter of freshwater was reduced by 9.8%.