In this article, we will show you the impact that shading solar panels has on the operation of the installation. We will tell you how to avoid shadows on the panels and how to connect panels into circuits so that the modules connected in strings work effectively.
Shading around solar panels
The basic rule when planning the arrangement of panels is to avoid shading. PV panels connected in series in chains work as their weakest link. This means that shading one module will have a very negative impact on the operation of the others. To avoid this, it is best to conduct a local inspection of the roof, taking photos of shadows from morning to evening to exclude shaded places. Such a vision should be carried out from March to September, because shading in the autumn and winter months does not have a significant impact on the efficiency of the installation, which is insignificant anyway.
Therefore, panels should not be used around chimneys. The solution would be to use optimizers, but their current price is over PLN 200 per unit for one panel. The point of using optimizers is justified if the panels are shaded randomly during the day and not for most of the day. The optimizers are connected to selected panels and connected in series with the rest of the array. The work of optimizers is to eliminate the negative impact of the shaded panel on the rest of the modules in the row.
Selection of panels into circuits
If the installation of panels is planned on two different areas with different angles of inclination or with different locations according to cardinal directions, such panels should be divided into two independent circuits. Most three-phase inverters have 2 independent MPPT inputs, which means that panels on separate circuits operate separately. Therefore, if one area is shaded in the evening, it does not affect the operation of the morning area. Additionally, you should not connect more than 24 panels per circuit, so for installations larger than 6kW, it is necessary to divide the installation into two strings, even though they would be placed on the same surface without shadows and angle differences.