Performance enhancement of stepped solar still coupled with evacuated tube collector

The provision of fresh water is the most important problem in developing countries. With the rising need for fresh water, it is vital to look for other sources. Solar energy is still one of the most essential and technically feasible applications of the sun. There are numerous varieties of solar stills; the basin type is the most basic and well-proven. The biggest disadvantage of a tra-ditional basin solar still is that it produces very little distilled water per unit area. Solar distilla-tion is one of the most basic method to remove pollutants including heavy metals, dust, salts, and microorganisms from water. When compared to rainwater, it produces more clean water. Using solar distillation technology, sea water can be converted to fresh water. In this study, a solar still with a single basin is compared against a concentrator with evacuated tubes and a stepped basin solar still to see which one produces the most output with the least amount of energy. The four cases are analyzed, and it is discovered that the productivity of case 1: a solar still with a single slope with constant flow rate is 1.05kg/m2 and the maximum temperature ob-tained during this case is 49.0°C at 3:00 PM. The productivity for case 2: single slope solar with secondary stepped basin is 1.32kg/m2 while the maximum temperature is about 61.8°C at 3:00 PM. The productivity of case 3: a solar still with a single slope linked to a compound parabolic concentrator is 1.47kg/m2 with a maximum temperature of 62.4°C at around 3:00 PM. The output of Case 4: a solar still with a single slope with secondary stepped basin and compound parabolic concentrator is 1.72kg/m2 with a maximum temperature of 70.2°C obtained at 3:00 PM. The efficiency of a solar still with a single slope and a secondary stepped basin with a compound parabolic concentrator is 63.8 % higher than the reference case.