Theoretical and experimental investigation on a single basin double slope solar still

Solar still, which converts available brackish or impure water into potable water, can be used to supply drinking water for the people living in arid and remote areas. But, this still is not popular because of its lower productivity. This research work presents the theoretical and actual performance of the single basin double slope solar still and explores the different methods to improve the efficiency. A single basin double slope still with overall size of 2.5 m x 1.5m x 1 m was fabricated and tested under laboratory conditions (still – laboratory) and in actual solar radiation conditions (still – solar) at Chidambaram (9o11’N, 77o52’E), a city in southern India. Experiments were conducted for different depths of water up to 0.2 cm and with different basin materials. Different wick materials like light cotton cloth, jute cloth and light sponge sheet were used. Aluminium rectangular fins arranged in length and breadth wise covered with cotton cloth and jute cloth were also used in the basin. The solid materials like quartzite rocks of different sizes, naturally washed stones, cement concrete pieces and, brick pieces and iron turnings were used in the basin. The above said solid materials were not used so far. Experiments were conducted using different glass thickness with different inclination and orientation and the variations in transmittance were studied. A regression equation was established, to calculate the transmittance of the given thickness glass plate at any place and at any time for given radiation conditions. The variations of energy losses at cover plates were studied.