Thermal and enviro-economic analysis of solar stills: Influence of fin geometry, size, and water depth

Abstract

Solar distillation is a promising technology for producing fresh water in remote and arid regions, leveraging renewable solar energy to drive evaporation and condensation processes. However, conventional solar stills often suffer from low efficiency due to limited heat transfer. This study investigates the enhancement of solar still performance through the integration of circular and triangular fins on the absorber plate, a novel approach aimed at maximizing heat absorption and improving evaporation rates. Experimental tests were conducted under the climatic conditions of Bhopal, India, to evaluate the effects of fin geometry on water productivity. The experiment was performed at three different water depths (15, 30 and 45 mm). The results demonstrate that the circular fins gives maximum yield of 1.4 L/day, while triangular fins gives 0.95 L/day. The maximum evaporative heat transfer coefficient was found 20.8 W/m²K at water depth of 15 mm in case of circular fin. The energy payback time (EPBT) was 1.29 years for circular fins and 1.99 years for triangular fins. The study provides a comparative analysis of fin performance, offering new insights into optimizing heat transfer mechanisms for more efficient solar distillation systems.