Energetic, exergetic, economic, and environmental analysis of a pyramidal solar still integrated with different PCM quantities

High solar intensity during peak hours could be utilised to sustain solar still yield over off-peak by employing phase change materials (PCMs). This work explores the influence of increased PCM quantity when incorporated into a pyramidal solar still, considering energetic, exergetic, economic and environmental approaches. Experimentally, two identical pyramidal-shaped solar stills were designed, fabricated and examined in a hot location, in which one of them was set as a reference while the other was incorporated with 2, 4 and 8 PCM cans. The stills were mainly analysed in view of their freshwater productivity, thermal efficiency, exergy efficiency, cost per litre of freshwater produced and potential CO 2 emissions mitigation. Findings indicated that the thermal performance and freshwater produced were augmented noticeably as the PCM quantity increased, accompanied by a high evaporative rate and basin water temperature. The daily accumulated freshwater was augmented as much as 38.7% at the highest PCM quantity over the reference still. Besides, the uppermost thermal and exergy efficiencies of the modified solar still with the maximum PCM quantity were 47.14% and 10.7%, respectively, over the reference still. Economically, the cost per freshwater produced declined by up to 23% at the highest PCM quantity, while increasing water quality by up to 98%. Likewise, environmental analysis indicated as high as 18.6% CO₂ emissions mitigation annually, emphasising the advantages of PCM integration with solar stills. Study outcomes highlight the role of incorporating high quantity PCMs to promote effective solar stills with low-cost freshwater production.