Numerical study on wave–wind coupling effects on hydrodynamics and light capture performance of offshore multi-body floating photovoltaic system

Offshore floating photovoltaic (FPV) systems have the potential to become important clean energy sources. However, the behavior of multi-body FPV under coupled wave–wind conditions are not fully understood. In this study, the hydrodynamics and light capture performance of FPV systems in coupled wave–wind co-directional conditions were numerically assessed by considering three different panel arrangements. This study utilized potential flow theory to conduct wave simulations and used Morison force to calculate the wind effect on the structure. The wind coefficient variation with pitch is innovatively considered in the present numerical method. The hydrodynamic results were compared with wave-only conditions to understand the effects of wind–wave coupling better. It was observed that wind has a significant effect on the surge motions of FPV systems in low-frequency waves. Compared with a pure wave condition, the average position in the vertical direction of the structure in a parallel arrangement sinks by about 12.4% owing to the vertical component of the wind load on the photovoltaic panel, while exhibiting a float rise in staggered and symmetrical arrangements. The coupling of wave–wind loads cause a sharp increase in both the mooring force and the horizontal connection forces at low frequencies. The insolation in the parallel arrangement was 13% greater than that in the staggered and symmetrical arrangements under the same conditions.