Performance studies on stacked and low pressure solar stills

Abstract

Water scarcity is one of the biggest challenges of our time. It is newlineestimated that by 2025, two-thirds of world s population may face water newlineshortages. Water is one of the most essential substances for human being newlineexistence. Even though the world is covered with 70% of water, the availability newlineof fresh water for consumption is very low. Inadequate water availability poses newlinecritical threat to both population and industrialization. Various methods such newlineas reverse osmosis, multistage flash distillation and electro-dialysis are newlineemployed to convert the saline and brackish water to potable water. The main newlinedrawback in the aforementioned methods is that they consume electric energy newlinefor its operation. newlineSolar still is a simple, economical and eco-friendly device that newlineconverts any impure water into potable water with the aid of inexhaustible and newlineclean solar energy. It works on the basic principle of evaporation and newlinecondensation replicating the natural hydrological cycle. The major setback for newlinecommercialization of a solar still is its low productivity. newlineIn the present research work, performance studies on a stacked solar newlinestill and a low pressure solar still has been carried out and various methods to newlineincrease the distillate output of the solar stills have also been analysed. A newlinestacked solar still consists of two basins stacked together resulting in an newlineincreased output for same base area. A single slope stacked solar still of base newlinearea 0.5 m2 was designed and fabricated using galvanized iron sheets and glass newlinecover. The productivity of the stacked solar still was compared with a newlineconventional single basin single slope solar still of same base area. newline