Investigation of the effect of a solar collector, nozzle, and water cooling on solar still double slope

Many nations, particularly those in rural places, are struggling with the freshwater crisis. Recently the best way to produce freshwater is done with solar still. In this study, four different solar stills were built and were labelled as conventional solar still (SSA), solar still with the addition of water cooling on the glass cover (SSB), solar still with the addition of a nozzle inside the solar still (SSC), and solar still with the addition of a solar collector (SSD). The four solar stills will be evaluated and compared under the same environmental conditions in Medan City, Indonesia (Latitude/Longitude/: 3° 47' 3.4908'' N/98° 41' 39.1956'' E). The temperature, freshwater productivity, exergy, energy, and economic analysis will be studied for the four solar stills. From the data, the glass temperature of SSC was higher than SSA in the range 08.00 -11.30. SSD was found to have the highest average energy and exergy efficiency. SSB has successfully increased freshwater production by 28.9% from 0.81 L/m2/day to 1.0436 L/m2/day. Moreover, SSB has the lowest cost compared to other solar stills, which only cost 0.193 $/L/m2