Numerical analysis and performance optimization of a solar photovoltaic–electrolyzer system with hybrid nanofluid-based cooling for sustainable hydrogen production

This study numerically investigates a hybrid solar photovoltaic-thermal (PVT) system integrated with a Proton Exchange Membrane Water Electrolyzer (PEMWE) for simultaneous electricity generation and green hydrogen production. To enhance thermal management, a novel sinusoidal cooling duct is incorporated beneath the PV panel, circulating a hybrid nanofluid consisting of water, graphene oxide, and silver nanoparticles. The PV module was modeled using realistic solar irradiation and optical absorption profiles, including radiative heat transfer and external heat losses. A parametric analysis was presented to assess the influence of sinusoidal turn numbers on electrical efficiency, thermal efficiency, total efficiency, pressure drop, performance evaluation criteria (PEC), hydrogen production, and CO2 mitigation. A multi-objective optimization approach was then applied to maximize total system efficiency while minimizing hydraulic losses. Polynomial regression models validated using Leave-One-Out Cross-Validation (LOOCV) was developed to establish relationships between design variables and performance indicators. The optimal configuration was obtained with four sinusoidal turns, achieving electrical and thermal efficiencies of 46.02% and 13.1%, respectively, with a total efficiency of 80.49% and a PEC of 1.52. Compared with conventional PV, hydrogen production and electrical efficiency improve by 9.12% and 9.3%, respectively. The addition of hybrid nanoparticles further enhanced system performance and temperature uniformity. Economic evaluation demonstrated a payback period of approximately 1.39 years, confirming the feasibility of the proposed design for sustainable solar hydrogen production.