Comparative Numerical Study on Nanofluid-Based Cooling Strategies in PVT Systems for Improved Thermodynamic and Electrical Performance

The study presents an optimization technique to improve photovoltaic-thermal module's performance by analyzing cooling effects facilitated by mono and hybrid nanofluids. The investigation evaluates the thermal performance of silver-water (Ag/water), aluminum oxide-water (Al2O3/water), and hybrid combinations of magnesium oxide and copper oxide with multi-walled carbon nanotube-water (MgO-MWCNT/water and CuO-MWCNT/water) nanofluids. The prototype model integrates four riser tubes and an absorber plate to facilitate heat transfer mechanisms. A novel approach is employed wherein each consecutive tube’s inlet is rotated by 180° to ensure uniform heat distribution across the solar panel absorber. Numerical simulations using computational fluid dynamics were conducted in ANSYS Fluent to assess the cooling effects of circulating nanofluids throughout the absorber plate. Results indicate that optimal electrical efficiency enhancements are achieved at a fluid velocity of 0.24 m/s with Al2O3/water at 10.7%, Ag/water at 10.78%, MgO-MWCNT/water at 10.69%, and CuO-MWCNT/water at 10.68%. The exergy efficiency values for the nanofluids, at the same flow rate, are 11.8% for Al2O3/water, 12.2% for Ag/water, 11.2% for MgO-MWCNT/water, and 11.4% for CuO-MWCNT/water. The results demonstrate the superior thermal and electrical performance of Ag/water, suggesting its viability for improving photovoltaic efficiency and supporting sustainable energy production.