Design, construction and performance analysis of a four-fold pyramid shaped solar still with different insulation materials and activated carbon

A four-fold pyramid-shaped solar desalination system has been constructed to produce fresh water for the coastal residents in Bangladesh. To evaluate the heat-storage effectiveness of activated carbon from sugarcane bagasse which was synthesized by KOH activation method and confirmed through SEM/EDS analysis was assessed in a prototype desalination setup. Among the four different insulating materials in the drawer-style chamber of solar still, the PE (polyethylene) foam combined with aluminum foil showed the most effective material for heat retention since it has a low emissivity with a minimum conductive heat transfer loss of 1.65 ± 0.44 W. With a solar radiation of 13.73 MJm -2 day -1 , the system produced 1.35 kgm -2 of water on November 22, 2023, in Bangladesh. After analyzing the freshwater properties, the salinity, pH, TDS, SG, ORP, and EC of fresh water have been found 0%, 6.95, 50 ppm, 1.003, -36mV, and 26 μScm -1 respectively. Moreover, the device has an efficiency of 22.64% with a payback period of 3.3 years. The average distillation value of developed solar still has been found 65% greater when activated carbon is present. The study also highlights technical optimization and economic feasibility and this solar desalination system presents a promising solution to alleviate freshwater scarcity in Bangladesh. • A four-fold pyramid-shaped solar desalination system has been developed. • Insulation materials and activated carbon was used to assess heat storage capacity. • PE foam with aluminium foil proved to be the most effective insulating material. • By introducing the activated carbon, desalination efficiency was increased up to 65%.