Electrothermal Coupling in Floating Photovoltaic Systems: A Modified Shockley Framework for Performance Enhancement

Floating photovoltaic systems are attracting increasing attention due to their enhanced thermal regulation and improved energy yield compared to land-based installations; however, accurately capturing their coupled thermal–electrical behavior under realistic environmental conditions remains a key challenge. In this study, a physics-based electrothermal framework is developed by extending the classical Shockley diode equation to explicitly incorporate water-assisted cooling effects. A floating photovoltaic-specific thermal correction is introduced to directly link environmental variables — including irradiance, ambient temperature, water temperature, and wind speed — to temperature-dependent electrical parameters. The results show that reduced operating temperatures significantly suppress the exponential increase in diode saturation current, leading to improved voltage retention and enhanced maximum power output. Comparative I–V and P–V analyses indicate that the performance gain of floating photovoltaic systems is predominantly voltage-driven, with predicted power improvements of ≈ 3–8% under typical operating conditions. Sensitivity and Monte Carlo analyses further demonstrate the robustness of the floating photovoltaic system advantages and highlight the dominant influence of water temperature and wind speed on system performance. The proposed framework provides a compact, physically interpretable, and computationally efficient tool for floating photovoltaic performance analysis, offering practical insights for system design and optimization.