Improving the effectiveness of photovoltaic thermal systems with nanofluids and NePCM in tropical climates

This manuscript examines advancements in photovoltaic/thermal (PV/T) systems enhanced with nanofluids and phase change materials (PCMs), with a focus on identifying research gaps and promoting commercial viability. A systematic literature review synthesizes findings from 50 empirical studies, highlighting substantial thermal and electrical improvements associated with the integration of these technologies in diverse operational contexts, particularly in tropical environments. The analysis reveals that thermal efficiency gains range from 5% in minimally optimized configurations to 72% in systems utilizing advanced hybrid nanofluids and conductivity-enhanced NePCM. Electrical efficiency improvements consistently fall between 5% and 12%, primarily attributed to reduced panel temperatures and enhanced heat removal. Notably, tropical regions are shown to achieve average thermal gains exceeding 25%, with peak values surpassing 60% under high-irradiation conditions. The study highlights critical future research directions, including the standardization of nanoparticle synthesis protocols, the expansion of long-term stability assessments, and the optimization of nanofluid formulations that balance heat transfer with pumping power. The integration of hybrid renewable systems and circular economy models for nanoparticle production also warrants further exploration. By outlining these findings and recommendations, this manuscript informs ongoing research efforts and establishes a comprehensive agenda for future investigations aimed at maximizing the performance and sustainability of PV/T systems. Ultimately, the insights provided in this review help bridge the gap between laboratory advancements and real-world applications, thereby fostering the adoption of innovative thermal-enhancement technologies in the energy sector.