Performance enhancement of pyramid solar still integrated with evacuated tube collector, phase change material, and fins: Thermal, exergy, economic, and environmental analysis

One important factor in the production of inexpensive drinkable water is solar energy. Because of this, solar distillation has become a widespread and green solution. Although a number of methods, such evacuated tube collectors (ETC) and phase change materials (PCM), have been investigated to enhance the performance of solar stills, the literature to date has not thoroughly investigated their synergistic integration with fins and PCM. In order to increase thermal efficiency and productivity, this study integrates evacuated tube collectors (ETCs), phase change materials (PCMs), and fins into pyramid-type solar still (PSS) technology. The unit was tested for 19 days in May–June 2024 in Mehsana, India (23.5880° N, 72.3693° E). The modified PSS (MPSS) exhibited a temperature differential between water and glass that was 1.08 times higher, achieving peak-hour productivity of 830 mL, compared to 550 mL for conventional PSS. Additionally, the MPSS demonstrated a 19.20 % increase in efficiency and a 49.20 % increase in daily yield. When considering both overnight and daytime cumulative productivity, the MPSS yields 6.8 L of distillate per day. This setup can be implemented in local communities, delivering high throughput at a cost of only $0.0094/L.