Designing a Solar PV Panel layout is relatively straightforward, especially on a small to medium scale. However, there are a few important factors to consider when setting your panels up which drastically affect power generation.
These are broadly divided into two factors:
- Orientation
In this article, we will go over the orientation of the Solar PV Panels.
Orientation:
The orientation of the panels is defined by the direction to which the panels face and by how many degrees they are tilted towards to that direction.
Azimuth:
The azimuth essentially indicates the position of the sun in the sky. Thus, for the purposes of Solar PV Panel layout design, it indicates the direction of the panels with respect to the cardinal directions (North, South, East & West).
There are two conventions used to denote Azimuth (position of the sun in the sky towards which the solar panels are pointed).
In the 180 convention, for the northern hemisphere, true south is 0⁰ while in the 360 convention, true south is 180⁰.
As a rule of thumb, in the northern hemisphere, the panels should face true south for maximum power generation. However, this is not always possible practically due to the orientation of the structure or the roof on which the panels are mounted.
Tilt:
The tilt is simply the angle the solar panel makes with the parallel. This is also known as the absolute tilt as we are disregarding the angle of the structure on which the panel is installed.
A tilt of 20⁰ to 30⁰ is generally ideal, however, the optimum angle on tilt varies significantly depending on the latitude of the location where the panels are to be installed and thus, Surface Orientation Plots for that location should be referred to when designing a Solar PV Panel Layout.
Surface Orientation Factor (SOF) Plots:
Surface Orientation Factor is defined as the ratio of annual incident solar radiation for a particular orientation to annual incident solar radiation for an optimally oriented surface. Thus, it is a percentage indicating the actual solar radiation received as compared to the maximum solar radiation received.
Shown below is a Surface Orientation Factor (SOF) Plot which shows the SOF plotted against various azimuths and tilts.
As we can see, for this particular location, the optimum orientation is an Azimuth of 194.16⁰ and a Tilt of 29.94⁰. However, we can see that that is a margin around the optimum orientation that would yield values of SOF >99.
Orientation of the Solar PV Panels is of critical importance when designing the layout and thus, choosing the optimum azimuth and tilt is paramount to ensure maximum power generation and thus, a maximum rate of return on your Solar PV Plant.