Wind Loads on Low-Profile, Tilted, Solar Arrays Placed on Large, Flat, Low-Rise Building Roofs

The author examined wind loads on low-profile, roof-mounted solar arrays, placed on large, low-rise buildings with nearly flat roofs by using scale models in a boundary layer wind tunnel. The author also examined the effects of building size and array geometry on enveloping curves of area-averaged pressure coefficients, typical of use for design. It was found that wind loads on the array increase with building size; normalizing the effective wind area by the building wall size leads to enveloping curves that collapse onto a single curve for each array geometry. For tilt angles less than 10 degrees, there is an approximate linear increase in the pressure coefficients as the tilt angle increases. For arrays with tilt angles of 10 degrees or more, the wind loads do not depend significantly on the tilt angle and are relatively constant. Roof zones for wind loads on solar arrays are larger than roof zones for bare roofs and depend on the array tilt angle.