Wind flow dynamics over a photovoltaic power plant: Comparison with a vegetated canopy

Large land parcels of photovoltaic (PV) parks are expanding rapidly worldwide to support the energy transition. Their growing footprint in rural landscapes raises concerns about the impact such a development has on local micrometeorology and surface–atmosphere exchanges. Yet, the aerodynamic behavior of PV canopies compared to existing land uses remains poorly understood. This study compared wind dynamics and turbulence under near-neutral conditions above a 140-hectare PV park and a nearby homogeneous pine forest in southwestern France. Results showed that turbulence within the PV canopy was highly anisotropic and strongly dependent on wind direction. Under winds perpendicular to the panel rows, the flow displayed characteristics typical of dense or row-structured vegetative canopies, with an inflection in the mean velocity profile, strong drag, and efficient momentum transport dominated by sweep motions. Parallel winds, however, produced weaker drag and turbulence, a logarithmic mean profile, and elongated streamwise structures typical of shear flows over weakly rough surfaces. Based on these findings, we proposed a physically based parameterization of the mean wind velocity profile for PV canopies, depending on the wind direction and key structural properties of the PV array. The parameterization combined a logarithmic law with a roughness-sublayer correction above the panels and an exponential–logarithmic formulation within. This parameterization enabled the introduction of directional aerodynamic effects of PV parks into land–atmosphere models.