Enhanced solar desalination via hemispheric distiller with thermal storage, heaters, and condensation: Exergoeconomic and environmental analysis

Abstract

The solar distillers suffer from low yield due to the intermittent solar radiation availability, inherent thermal losses, and suboptimal operating temperatures due to design limitations. This study proposes a novel hemispherical -shaped solar distiller (HSD) with integrating jute wicks and thermal storage materials (TSM – paraffin wax mixed with graphite and aluminum oxides nanoparticles) for enhanced potable water production in remote areas. The HSD had 5000 cm² projected area. Compared to the conventional solar distiller (CSD), the freshwater production of HSD was improved by 90.74 % and 41.73 % with and without TSM, respectively. The implementation of electric heaters (20 W) and an external condenser further propels freshwater production, reaching a significant 145 % improvement compared to that of CSD. The HSD exhibits superior performance as compared to CSD based on the freshwater production and efficiency parameters. With all enhancements integrated, the daily distillate yield reached 6370 mL/m², and both energy and exergy efficiencies were 48.2 % and 4.9 %, respectively. Moreover, the environmental factor for CSD, HSD, HSD with TSM, HSD with TSM & heaters, and HSD with TSM, heaters & condenser is determined as 13, 18.4, 24.8, 29.7, and 26 tons CO₂ a year respectively. Economically, the HSD proved its merit with a significantly reduced cost per liter of distilled water. While the CSD had a cost of $0.32 per liter, the HSD with all enhancements reduced this cost to $0.19. In conclusion, the HSD with integrated jute wicks, TSM, heaters, and condenser represents a significant advancement in solar desalination technology.