Freshwater scarcity is a critical worldwide challenge, especially in remote and arid regions where conventional desalination methods are often impractical due to high energy and cost requirements. Solar stills offer a simple and sustainable solution; however, their low productivity limits their practical application. This study investigates a low-cost approach to optimize the performance of a hemispherical solar still by integrating natural sand as a heat storage material mixed with different proportions of waste aluminum filings to improve thermal conductivity. The system was experimentally tested under real outdoor conditions, and its thermal and thermodynamic performance was evaluated. The results show a significant improvement in freshwater production, increasing from 4.01 to 7.36 L center dot m- 2 center dot day- 1, representing an enhancement of approximately 83%. Energy efficiency increased from 17.41% to 33.45%, while exergy efficiency improved from 4.76% to 15.45%. The economic analysis showed a reduction in the unit water cost from 0.0285 to 0.0101 $center dot L- 1 (approximate to 64% decrease), along with a shortened payback period from 242 to 55 days, confirming the economic feasibility of the proposed system. These improvements are attributed to enhanced heat storage and more effective heat transfer within the system, which extends evaporation time and reduces thermal losses. The findings demonstrate that combining low-cost materials with improved heat transfer mechanisms can significantly enhance solar still performance. The novelty of this work lies in the integrated use of sand-based thermal storage with distributed waste aluminum filings, providing a simple, scalable, and cost-effective solution for sustainable water production.