Enhanced distillate yield of acrylic pyramid top cover solar still with and without tar coated blue metal

An innovative work had been carried to increase the distillate yield of the solar still by replacing the single slope cover by means of parabolic cover. Advantage of pyramid top cover is that the amount of solar radiation entering the system in more when compared to other types of top cover. The top pyramid cover is made up of transparent acrylic sheet of 3 mm thickness of transmittance 88%. Pyramid top cover of diameter 0.75 m and height 0.30 m is designed for the still. It is designed by joining the two portions of the acrylic sheet.