Abstract:

As an emerging offshore solar solution, floating photovoltaic technology can support the energy transition in coastal regions, expand the utilization of marine resources, and has broad development prospects. It is expected to provide significant support for the country's “3060” dual-carbon strategy. To address the current lack of research on power generation calculation methods for offshore floating photovoltaic systems, this study proposes a power generation calculation model based on the wave dynamics and other marine environmental characteristics of the target sea area. First, based on wave mechanics and floating body hydrodynamics, and considering the steepness of the target sea area d as a small value (wave height h / wave length l ≤ 1) as a boundary condition, the study uses the irradiation energy efficiency η and the time-averaged tilt angle ε to quantify the long-term impact of waves on photovoltaic modules. This yields an equivalent irradiance objective function for the inclined surface under regular wave action. Second, considering seawater reflection, evaporation, and convection, the influence of module backside and water surface cooling effects is incorporated. A practical calculation formula for backside irradiance and a water surface cooling effect factor are introduced to characterize the positive gains from the module backside and water surface cooling. Finally, a comparison with field measurements at the target site demonstrates that the calculated values deviate from the theoretical values by less than 10%, which falls within the expected margin of error.

Key words: offshore floating photovoltaic, power generation calculation, irradiance efficiency, time-averaged tilt angle, positive gain