Log In / Sign In

How to calculate the minimum distance between PV panels?

The minimum distance between rows of PV panels when placed on the ground in an open space or on a flat roof is important to avoid the shading effect.

The choice of this distance is closely related to our geographic location, as well as the dimensions of our panel, its orientation and the angle that makes our panel with the ground. Based on these parameters, we are able to calculate the minimum distance between the panels.

Let’s start with the geographic location. In this context, the height of the sun’s elevation above the sky is important – as we know, it is the lowest on the winter solstice, i.e. on December 22. Now, depending on the geographic location – the hemisphere, zone and the exact location expressed in degrees, we can calculate the height of the sun.

The next step is to calculate the height of our panel. For this we will need the angle of inclination between the panel and the ground, as well as the length of the panel. Of course, knowing the specific measured height makes it easier, but unfortunately at the design stage we rarely have such information.

We use the law of sines to calculate the height:

L/ sin90  =  h/ sin(a)

By transforming,

h= (L / sin90) * sin(a)

Knowing the height and angle of the sun’s elevation, we can determine the minimum distance between the panels:

D= h / tan(Hs)

In the next update of our application, we will introduce a calculator that will allow and facilitate the calculation of the minimum distances between panels for any place on Earth!