Performance optimization of photovoltaic modules through hybrid thermal management with SiO2 and MWCNT nanofluids

• A hybrid PV/T system with serpentine copper tubes, louver fins, and nanofluids was tested outdoors. • Direct attachment cooling lowered PV temperature by 7–8 °C versus the reference module. • MWCNT nanofluid (0.05 wt%) in direct mode boosted power by 64.5% and efficiency by 3% over reference module. • Direct cooling delivered higher thermal energy (556.7 W) and exergy (281.4 W) than the indirect setup. • Exergy destruction fell by 54% and entropy generation halved, enhancing PV/T performance. Photovoltaic-thermal (PV/T) systems enable simultaneous electricity and heat generation; however, elevated module temperatures reduce efficiency. Nanofluid cooling offers an effective mitigation strategy, though concerns regarding long-term stability persist. This study experimentally investigates silicon oxide (SiO 2 , 0.1 wt%) and multi-walled carbon nanotube (MWCNT, 0.05 wt%) nanofluids in direct and indirect serpentine copper tube-fin PV/T configurations using a 0.55 m 2 module. A distinctive contribution is the experimental benchmarking of direct versus indirect cooling with these nanofluids, supported by integrated energy, exergy, and uncertainty analyses. Results indicate that direct cooling consistently outperforms indirect methods due to lower thermal resistance. MWCNT nanofluid demonstrated superior thermal conductivity and heat transfer, achieving up to 395.5 W higher electrical power output compared to the reference module, while SiO 2 yielded a 249.3 W improvement. The thermal energy generated in direct and indirect configurations reached 556.7 W and 321.3 W, respectively. Exergy analysis confirmed enhanced energy quality recovery, with direct MWCNT cooling achieving 281.4 W compared to 122.3 W for the indirect configuration. Entropy generation analysis showed lower irreversibility for direct cooling (0.67 W/K), and Reynolds number calculations confirmed laminar flow of the cooling fluid. Overall energy efficiencies were 71.5 % and 46.7 % for direct and indirect configurations, respectively. These findings highlight the strong potential of nanofluid-assisted direct cooling, particularly with MWCNTs, to significantly enhance PV/T performance. Future work should focus on addressing nanofluid stability, durability, and economic viability for practical deployment.