LAUSR

Abstract This paper presents a new stepped solar still proposed to improve the daily productivity of the conventional basin type solar still (CSS). An internal Multi-Tray Evaporator (MTE) was integrated against the still rear-wall to act as an additional evaporation area. The MTE's effect on the still performances has been evaluated through experimental tests under different meteorological conditions in the region of Adrar-Algeria. The still productivity improvement is demonstrated through a comparative study between the proposed solar still and the conventional still. The experimental data show that the productivity of the proposed stepped solar still is higher than that for conventional still by about 47.18–104.73%. It was found that the estimated cost of distilled water and the payback period, for the stepped solar still are 0.01 $/kg and 70 days, respectively. While, for the simple solar still, they are estimated at 0.0145 $/kg and 100 days.