Improving the efficiency and productivity of solar distillation by creative design and heater and baffle integration

• Performance of cords wick hemispherical solar still (CWHSS) is investigated. • Effect of using baffles and electric heaters on CWHSS performance is tested. • Highest yield was obtained for CWHSS-B with heaters. • Highest yield rise for CWHSS-B with heaters was 206 %. • Best energy efficiency for CWHSS-B with heaters was 59.5 %. The hemispherical solar still (HSS) is a simple device used to desalinate saline water, but it has low productivity. This study aimed to enhance the evaporation rate of a hemispherical solar still (HSS) through several design modifications. The main innovation involved integrating an upper absorber with hanging wick cords, creating a modified system called the cords wick hemispherical solar still (CWHSS). Additionally, electric heaters powered by photovoltaic panels were incorporated to further boost performance, along with the introduction of squared baffles inside the CWHSS. Experimental results showed that the highest efficiency was achieved with the CWHSS incorporating baffles, heaters, and a condenser (CWHSS-B), leading to a 258 % increase in distillate output and a 66.5 % thermal efficiency. Under optimal conditions, the distillation rates were 4000 mL/m²/day for the HSS and 14,300 mL/m²/day for the CWHSS-B with heaters. Furthermore, the cost of water treatment was calculated at $0.022 per liter for the HSS and $0.016 per liter for the CWHSS-B, indicating significant cost benefits with the modified design.