Hybrid PVT integrated pyramid solar still: 11E, sustainability, and sustainable development goals assessment

Abstract

Photovoltaic thermal (PVT) integrated solar stills (SSs) can address the challenges associated with electricity scarcity and water desalination. The experiment encompasses a synergistic approach of delivering the heated fluid from the PVT with phase change materials (PVT/PCM) and PVT integrated hybrid nano-materials with fin (PVT/HNPCM/Fin) setups to the water basin of the modified pyramid SSs for enhancing the evaporation rate. A comprehensive analysis is conducted on the impact of hollow circular fins, black sand, hybrid nano-particles with PCM and sponge in SS cases. For PVT scenarios, the effects of hybrid nano-enhanced PCM and fins in serpentine copper pipe layout at an average flow rate of 0.0021 kg/s are also analyzed using 11E sustainability matrices. Modified SS exhibited the highest productivity of 4.109 L/m²/day, with a cost reduction of about 94.13 % per liter. Consequently, the PVT/HNPCM/Fin system achieved thermal efficiency of 75.11 % and a relative improvement in electrical energy efficiency of approximately 15.70 % over the traditional PV module. Modified SS exhibits the highest exergo-enviroeconomic factor among the other SSs, with a difference of about 30.57 %. At a moderate cost, modified SS with PVT integration has a high capacity to produce thermal energy for distillation and 6.98 tons of CO₂ emissions mitigation possibilities over the lifetime. Finally, the proposed modification and assimilation not only supports the sustainability of water purification processes with clean electrical energy generation but also contributes significantly to achieving multiple Sustainable Development Goals (SDG 6, 7 and 13) related to energy, water, climate, and economic development.