Performance analysis of partially shaded pyramid solar still desalination system

Abstract

newline Solar still is a simple, economical and renewable energy system that converts any saline water into freshwater with the help of inexhaustible and clean solar energy. It works on the basic principle of evaporation and condensation which replicates the natural hydrological cycle. The major hindrance to the commercialization of a solar still is its low productivity. In the present study, performance studies on partially shaded pyramid solar still are carried out. The square pyramid transparent cover is used as the top cover of the partially shaded pyramid solar still. The square pyramid has four sides and each side is named as per the direction. Each one of the sides is shaded in the square pyramid transparent cover. The single side or direction shaded is known as 25% of shading in the transparent cover. Similarly, two sides are 50%, and three sides are 75%. Totally, fourteen configurations of experiments are conducted in the partially shaded pyramid solar still for improving the freshwater yield. Fifty percent of shading in the transparent cover produced higher freshwater yield compared to 25 and 75%. The partial shading increased the productivity of freshwater yield by reducing 4 °C of the transparent cover temperature compared to conventional pyramid solar still. The north and south directions shaded (50% of shading) produced 4% higher freshwater yield compared to conventional pyramid solar still. The theoretical analysis was carried out on the conventional and modified solar still. The transmittance, absorbance and reflectanceof the top cover, the inclination angle of the top cover, the level of brine in the basin and the average distance between the evaporating and condensing surfaces are studied theoretically and optimized so as to test the experimental setup under the best operating condition.