How Are Wind Loads Calculated on Solar Panels and Racking?

I establish the wind design basis from the adopted code edition: mapped wind speed for the risk category, exposure category from the surrounding terrain, topographic factor where the site sits on or near elevated terrain, and the ground elevation factor where the code requires it. The array height above grade sets the velocity pressure profile — low to the ground helps, but not as much as intuition suggests. Every parameter is documented with its source on the structural drawings, because the wind design is only as defensible as the inputs behind it.

Pressure coefficients translate wind speed into force on the panels, and the right coefficients depend on the mounting: ground-mounted arrays, rooftop systems, and carports each have their code path, with wind-tunnel data substituting where the geometry falls outside the code's tables. I apply the edge, corner, and interior zones across the array layout, then carry the resulting forces through the documented load path — module to clamp to rail to frame to foundation — checking each component at its governing load combination. The foundation reactions from this analysis are what the geotechnical design builds on.

A wind load analysis is complete when it clears this checklist. Wind is the load that finds every shortcut in the structural design. • Design wind speed, exposure, and topographic factors documented per the adopted code • Pressure coefficients selected for the mounting type with edge and corner zones applied • Full tilt range analyzed for trackers including the stow position • Load path checked from module clamps through racking to foundation reactions • Foundation design based on the wind reactions including uplift and overturning