Abstract
The thermodynamic analysis of crushed gravel sand and biomass evaporator assisted solar still (CBSS) using the second law has been explored in this study, and the results have been compared to conventional solar still (CSS) in same climatic conditions of Coimbatore city in India. The saline water and air vapour were pre-heated before entering the solar still basin using the thermal energy extracted from crushed gravel sand and biomass evaporator. The air vapour mixture and saline water temperature of CBSS were greatly improved by 23.2% and 23% than CSS, respectively. The maximal cumulative productivity and exergy efficiency of CBSS were found to be 51% and 35% greater than CSS, respectively. The diffused heat rate observed in both the solar stills were estimated using entropy analysis and the results revealed that the highest entropy observed in CBSS was 60.7% higher than CSS. In CBSS, the basin and saline water exergy destruction was about 12% and 22% higher than CSS, respectively. The results demonstrated that the CBSS can greatly lower the demand for potable water.