Experimental performance enhancements of a stepped solar still using bio-inspired leaf shaped copper fins

To achieve global sustainability goals, particularly access to clean water and sanitation, requires innovative, off-grid desalination technologies, such as solar stills. Conventional designs do offer solutions, but are limited by low productivity, preventing them from widespread applications. We aim to address this challenge by integrating bio-inspired copper fins, modeled after Maple, Banana, and Willow Leaf geometries, into a square stepped solar still. These fins, fabricated from 1.5 mm copper sheet, were tested against a finless baseline under real-world conditions. Average daily efficiency was tested against a baseline finless still efficiency of 0.2327. All 3 designs showed improvements in efficiency to 0.2807, 0.2997, and 0.3013 for Maple, Willow and Banana respectively with Willow Leaf geometry providing better geometric efficiency as well (84.79%/m2). The use of bio-inspired fins augments heat transfer and evaporation rates, thus increasing the viability of stepped solar stills. This work presents a practical, sustainable solution for the current water security issues and contributes directly to sustainability goal 6, especially for remote and off-grid communities.