JA11.3 Shading

The PV array shall meet either JA11.3.1 or JA11.3.2.

JA11.3.1 Minimal Shading Criterion

The minimal shading criterion is that no obstruction is closer than a distance (“D”) of twice the height (“H”) it extends above the PV array. (See Figure JA11-1 for an artistic depiction of “H” and “D.”) As Figure JA11-1 illustrates, the distance “D” must be at least two times greater than the distance “H.” All obstructions that project above the point on the array that is closest to the obstruction shall meet this criterion for the array to be considered minimally shaded.  Any obstruction located north of all points on the array need not be considered as shading obstructions.  Obstructions that are subject to this criterion include:

(a)  Any vent, chimney, architectural feature, mechanical equipment, or other obstruction that is on the roof or any other part of the building.

(b)  Any part of the neighboring terrain.

(c)  Any tree that is mature at the time of installation of the PV system.

(d)  Any tree that is planted on the building lot or neighboring lots or planned to be planted as part of landscaping for the building. (The expected shading shall be based on the mature height of the tree.)

(e)  Any existing neighboring building or structure.

(f)   Any planned neighboring building or structure that is known to the applicant or building owner.

(g)  Any telephone or other utility pole that is closer than 30 feet from the nearest point of the array.


Figure JA11-1: The Minimal Shading Criterion Artistic Depiction of "H" and "D"

JA11.3.2 PV Array Geometries Performance Input

If the PV array does not meet the minimal shading criterion as specified in JA11.3.1, then the detailed geometries of the PV array shall be described in the performance method.