Wind Load Basics for Solar & Steel Structures
ENSOL Engineering TeamPublished 2026-02-011 min read
Wind is usually the governing load on solar mounting structures. In India it is calculated under IS 875 (Part 3), which turns a site's basic wind speed into a design pressure on the modules and frame.
Basic wind speed
IS 875 (Part 3) maps India into basic wind speed zones from about 33 m/s to 55 m/s. Coastal and cyclone-prone regions carry the higher values.
From basic to design wind speed
The basic speed is modified by risk (k1), terrain and height (k2), topography (k3) and importance/cyclonic (k4) factors to give the design wind speed. Design wind pressure is proportional to the square of that speed.
Because pressure scales with speed squared, a modest increase in wind speed raises loads sharply — which is why site-specific design matters.
Loads on the array
Force and pressure coefficients convert wind pressure into uplift, drag and overturning on the tilted module plane and the supporting frame, which then size the members and foundations.