Performance Improvement of Conventional Solar Distiller Using Castor Seeds: Energy, Exergy, and Economic Analysis

ABSTRACT Freshwater scarcity and the growing environmental impacts of fossil‐fuel‐based desalination have accelerated the development of ecological solar desalination technologies. However, the low productivity of the Conventional Solar Distiller (CSD) limits its common application. To address this challenge, this experimental study investigates the use of castor seeds from bio‐waste as a low‐cost thermal energy storage material to enhance the output of a CSD. This experimental research investigates a CSD utilizing bio‐waste energy storage materials, specifically castor seeds. The calculation of heat transfer, thermal efficiency, and exergy efficiency has been carried out. Results reveal that the CSD containing castor seeds achieved a 78.57% improvement in daily yield, from 1.96 to 3.5 kg/m 2 . The daily average thermal and exergy analyses reveal that CSD containing castor seeds achieved efficiencies of 36.19% and 5.06%. The diurnal average energy and exergy efficiencies of the CSD containing castor seeds were 94.84% and 120.37% higher than those of the CSD without castor seeds. The CSD's payback period is 1.4 years, and the CSD containing castor seeds was reduced to just 0.7 years.