Investigation of the effect of different absorber plate configurations of hemispherical solar still

A significant global challenge is potable water scarcity. Solar stills (SS) offer a simple, efficient solution using renewable energy for desalination. This study experimentally investigates the effect of absorber plate configuration and mass flow rate on the thermal performance of a hemispherical solar still (HSS). Three absorber plate configurations were chosen: cone, funnel, and funnel stepped. Experiments were conducted at mass flow rates of 0.033 kg/s, 0.066 kg/s, and 0.1 kg/s on the 12th, 13th, and August 14, 2023. The experimental results indicated that the best configuration was achieved for the hemispherical funnel stepped solar stepped (HFSSS) along the hemispherical cone solar still (HCSS) and hemispherical funnel solar still (HFSS). The best performance was achieved by the HFSSS at the lowest mass flow rate of 0.033 kg/s. The average daily productivity and the average daily thermal efficiency of the HFSSS at the lowest mass flow rate of 0.033 kg/s increased by 62 % (4.61 L/m2. day for the HFSSS versus 2.84 L/m2.day for the HCSS) and 67 % (42 % for the HFSSS versus 25 % for the HCSS), respectively, compared to the HCSS. In addition, the cost analysis shows that the HFSSS was a cost-effective configuration compared to other SSs.