Numerical investigation of the wind loading exerted on an East-West (EW) ground mount solar system in low-rise scenarios.*

The wind loading is a cost driver of photovoltaic (PV) systems as it has a direct impact on structural requirements. A reduction in the wind loads experienced by PV systems is expected to reduce initial capital and operational costs, improving its technical and economical feasibility.  In this study, Reynolds-averaged Navier-Stokes simulations have been performed to investigate the mean wind load exerted on an East-West (EW) fixed tilt ground mount structure. Due to the industry interest to model low-rise scenarios, ground clearances of 250, 350, and 550 mm at Reynolds number of 1.478×10⁷ were tested for wind directions of 0°, 40°, and 90°.   The system investigated here is composed of 50 PV modules (2x1m), arranged in 5 E-W bays at 10° pitch.  For the same ground clearance, the results indicated that, at 40° wind direction, the system experienced the highest uplift, whereas, at 90°, the system produced downforce.  For the 40° and 90° wind directions, the individual east and west panels produced wind loads in opposite directions, where the west-facing panels tended to generate downforce and the east-facing panels tended to create uplift. It has also been demonstrated that the total uplift increased as the structure was raised from the ground, whilst leading edge modules experienced a relative reduction in uplit. This trend is due to the higher airflow velocities in the atmospheric boundary at higher ground heights and the reduction of the ground effect, which led to an airflow deceleration underneath the system and a change in the effective incidence angle of the flow.