Solar still technology is recognized as an economical and environmentally friendly option; however, its productivity and thermal efficiency remain limited. Earlier studies utilizing porous and recycled materials have achieved only modest performance gains, mainly due to inadequate thermal storage and weak evaporation intensification. To address these challenges, the present work investigates the enhancement of distilled water productivity in a conventional solar still by introducing a peat–perlite composite material. A comparative assessment between a conventional solar still (CSS) and a modified solar still (MSS) incorporating the peat–perlite blend was conducted under identical outdoor conditions. The estimation of thermal energy transfer coefficients inside the solar still was conducted utilizing a mathematical model formulated by Kumar and Tiwari. The introduction of the peat–perlite blend significantly improved the evaporative heat transfer coefficient, showing an increase of 118.74% relative to the CSS. Moreover, the MSS achieved a 79.65% enhancement in cumulative distillate yield and improvements of 49.93% and 73.34% in mean thermal efficacy and exergy efficacy, respectively, compared with the conventional system. Economic evaluation indicated a 41.89% reduction in the per-litre cost of distilled water production, while environmental analysis revealed that the peak total lifetime carbon credits of the MSS were 95.07% higher than those of the CSS.
Kumar et al. (Thu,) studied this question.