Maximizing thermal management of photovoltaic-thermal systems with proper configuration of porous fins and phase change materials

Effective thermal management is crucial to enhance the performance and longevity of photovoltaic-thermal (PVT) systems. Phase change materials (PCMs) offer a promising solution for absorbing excess heat from PV modules; however, their poor thermal conductivity limits their effectiveness. This work explores the incorporation of porous fins within PCMs to improve heat absorption and thermal regulation in PVT systems. A detailed mathematical model is developed to analyze the effects of varying fin porosity (0.85-0.95), fin thickness (7-21 mm), fin height (7-21 mm), and fin inclination (- 15 degrees-30 degrees) on PCM melting and PVT cooling performance. Results show that optimally configured porous fins significantly enhance PCM melting rates and heat extraction from PV cells. Incorporating optimal fins reduces peak PV temperatures by up to 5 degrees C compared to PCM alone at irradiation rate of 1000 W/m2. Meanwhile, reducing the fin thickness from 21 to 7 mm accelerates the overall PCM melting rate by 14 %. The cooling performance also shows a nonlinear increase with fin tilt angle, with maximum enhancement occurring at 15 degrees downward tilt for the studied configuration. The optimized fin-enhanced PVT design achieves 3.1 % higher electrical efficiency and 15 % increase in thermal efficiency compared to conventional PCM-PVT systems without fins. Findings provide design guidance to harness porous fins for maximized PCM-based cooling of PVT systems.