In-depth analysis of solar desalination systems integrating heat storage and wick materials: A multi-dimensional evaluation

Abstract

This study aims to improve the performance of both conventional (CPSD) and modified (MPSD) square pyramid solar distillers (SDs) by using heat storage materials like gravels (G), small gravels (Chips), black cotton cloth (C), and jute (J). The MPSD features fins and paraffin wax under the basin. Experiments were conducted in Greater Noida, India during October 2023, with six configurations: CPSD, MPSD, MPSD+G, MPSD+Chips, MPSD+G+C, and MPSD+G+J. The study assessed productivity, energy, exergy, economic, environmental, enviro-economic, and sustainability aspects. In first set of experiments, MPSD showed improvements in daily yield, energy and exergy efficiency by 13.51 %, 13.27 %, and 28.08 %, respectively, compared to CPSD. In second set of experiments, MPSD+G demonstrated superior performance over MPSD+Chips and MPSD. In third set of experiments, MPSD+G+C demonstrated superior performance compared to MPSD+G+J and MPSD+G. The enhancements in daily yield, energy, and exergy efficiency were 12.8 %, 19 %, and 27.07 % greater than MPSD+G, respectively. Compared to CPSD, MPSD+G+C achieved the highest energy and exergy improvements of 64 % and 172 %, respectively. The energy production factor for configurations ranged from 1.69 to 4.24 per year, with an energy payback period of 0.24–0.59 years. MPSD+G+C reduced the payback period and cost per liter by 26 %, enhanced enviro-economic parameters by 39.46 % compared to MPSD alone, and achieved a carbon mitigation of 15.53 tons. Exergetic sustainability of SDs is assessed through improvement potential, sustainability index, environmental effect factor, and waste exergy ratio. The findings indicate that cotton-based SDs achieve 8 % higher productivity than those using jute.