Abstract This study presents an upgraded double-deck solar still design incorporating a solar air heater and reflector to enhance water distillation performance. The research focused on evaluating the performance, economic value, and environmental impact of these upgrades. Experimental results demonstrated that the addition of a solar air heater and reflector significantly increased the efficiency and output of the solar still. The upper layer of the still consistently outperformed the lower, with maximum efficiency reaching up to 86% under optimal conditions. The upgrades resulted in a substantial increase in water production, with the upper layer producing up to 332 ml of distilled water at peak times, compared to 180 ml in the unmodified still. From an economic perspective, the enhanced system offers a cost-effective solution for water purification, reducing reliance on traditional energy-intensive methods. The environmental benefits are equally noteworthy, as the system harnesses renewable solar energy, reducing carbon emissions and promoting sustainable water management practices. Overall, the upgraded double-deck solar still provides a viable and eco-friendly alternative for water distillation, with significant improvements in both performance and environmental impact. The annual material benefits were 126$, Payback Period (years) 4.76 years, and CO₂ emissions were 800 kg CO₂/year.
