Experimentally Investigation of Exergy Analysis of Photovoltaic-Thermal (PVT) Water Cooling

This study presents an experimental investigation into the exergy performance of a photovoltaic-thermal (PVT) water cooling system equipped with copper fins in two distinct geometries-cylindrical and rectangular-under varying water flow rates (1, 3, and 5 L/min).Conducted under real environmental conditions, the research aimed to optimize heat dissipation and evaluate system efficiency enhancements resulting from different fin designs and cooling intensities.The results show that electrical efficiency improved significantly with increased water flow, reaching a peak of 64% electrical exergy efficiency using cylindrical fins at 5 L/min, compared to 60% for rectangular fins under the same conditions.Thermal efficiency also increased, with cylindrical fins achieving up to 80% at 5 L/min, outperforming rectangular fins which reached approximately 70%.However, thermal exergy efficiency exhibited a decline under higher surface heat flux due to increased irreversibilities, with rectangular fins slightly outperforming cylindrical fins by maintaining lower exergy losses (-13% vs. -15%).Overall exergy efficiency decreased with increasing surface heat flux but remained more stable at higher flow rates, with cylindrical fins maintaining 0.1-0.12compared to rectangular fins' 0.09-0.11.These findings underscore the importance of optimized thermal management, demonstrating that combining higher water flow rates with advanced fin geometries-particularly cylindrical fins-can significantly enhance energy and exergy performance in PVT systems, thus supporting their application in sustainable energy technologies.