Abstract Solar stills (SSs) often suffer from low freshwater productivity, limiting their practical applications. This study aims to enhance productivity while minimizing cost. Four novel absorber configurations were numerically investigated using COMSOL Multiphysics: a traditional V‐corrugated absorber (V) and three novel designs, namely V with a longitudinal fin (VF1), V with a concave (VC), and V with a concave and double fins (VCF2). Key geometric parameters (absorber height, fin height, and number of segments) were optimized. For V and VC absorbers, maximum productivity was achieved at an absorber height of 10 mm, where the tip reached the water surface. For VF1 and VCF2 absorbers, optimal performance was achieved at a fin height of 7 mm, representing 70% of the total absorber height. With 15 segments, the daily productivities were 4. 24, 4. 42, 5. 67, and 6. 21 L/m 2 for V, VF1, VC, and VCF2, respectively, representing a maximum enhancement of 46. 3% relative to the traditional V absorber. Reducing the number of segments to 10 decreased productivity for all configurations. Economic analysis revealed that the VCF2 with 15 segments achieved the lowest cost per liter (0. 014) and the shortest payback period (PBP) (3. 2 months), corresponding to a 30% reduction in cost and a 27. 2% decrease in PBP compared with the traditional V absorber. Overall, the optimized VCF2 design offers a thermally efficient and economically viable approach for improving SS performance.
Toulan et al. (Sat,) studied this question.