Improvement of Solar Still Productivity by Energy Absorbing Plates

Document Type: Research Article


1 Department of Mechanical Engineering, SKV University, Gujarat, India

2 Department of Mechanical Engineering, Silver Oak College of Engineering & Technology, Gujarat, India


A solar still is a viable option when the demand of potable water does not exceed more than 3 litres. Enhancement in distillate output from the solar still is a main goal of many researchers all over the world. In this research, the effect of copper and aluminium plates on distillate output is investigated experimentally as well as theoretically at different water depths under the same climate conditions. In solar stills, first we used solar still augmented with copper plates, second with aluminium and third without any plate called passive solar still. An energy balance equation was applied to solar still for calculation of theoretical distillate output of a solar still with different plates. Three experiments still of 1 m2 in area were constructed from locally available materials. In this work, it was found that the experimental and theoretical results are in good agreement. It was also found that using copper plate in a solar still increases distillate output by 20% (at water depth of 3 cm) and 32% (at water depth of 6 cm) compared with passive solar still, and using an aluminium plate increases distillate output by 10% (at water depth of 3 cm) and 20% (at water depth of 6 cm).


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