How does the orientation and inclination of the solar panels affect?

In this article we will talk about the orientation and inclination of the solar panels, how these variables affect the efficiency of the solar panels.

How does the orientation and inclination of the solar panels affect?

The inclination of the solar panels is a fundamental factor when optimizing the capture of solar energy in a photovoltaic installation. Determining the appropriate angle for the latitude where the photovoltaic system is located is one of the first steps that we must tackle with any photovoltaic design.

Irradiance on inclined surfaces:

The solar radiation that reaches the solar panels placed perpendicular to the direction of propagation of the solar radiation, will always be greater than if the same plate is placed at an angle other than that optimum perpendicular to the radiation.

By varying the azimuth and solar height throughout the day and year, the  optimal angle of  inclination of solar panels on a given surface is not always constant, since as we say, it varies throughout each hour of the day and throughout of each day of the year.

We see it more clearly in the following image where the tilt angle and azimuth have been highlighted:

Orientation of the solar panels:

Not only the inclination, but also  where the solar panels are oriented , or in other words, their deviation from the South (which is defined as azimuth) will affect power generation to a greater or lesser extent.

Therefore, the ideal situation would be to place the solar panels of the photovoltaic installation   in a structure whose inclination and orientation were progressively adapting to each hour of the day and each day of the year in order to always be perpendicular to the incident solar radiation.

This is usually achieved with one or two-axis solar tracker type systems, which, as their name already indicates, carry out a job of monitoring the optimum tilt point at all times.

However, because solar trackers have   high maintenance , are very expensive, and are only used in large on-ground solar gardens, the most common thing in  photovoltaic installations  connected to the grid or photovoltaic self –  consumption  is to use  solar panels structure  of fixed mounting, with a fixed angle of inclination.

As an example of how the variation in inclination of solar panels affects in relation to the irradiance received, and therefore in the greater or lesser energy that can be generated from that irradiance, an example of a graph for a photovoltaic installation in Spain where the solar radiation received during a year on a solar panel has been calculated depending on the azimuth and the angle of inclination as a percentage with respect to the maximum:

Irradiance on a solar panel as a function of its inclination and azimuth for a certain place

You can clearly see what we have commented throughout the article, as well as that there is a region (highlighted in dark) where the   received irradiance is almost identical even though the inclination is not optimal. That is, slight deviations in the angle of inclination and azimuth have almost no effect on the irradiance received.

Conclusions:

It is clear that the inclination angles in solar panels, as well as their azimuth orientation (deviation from the south) are fundamental when it comes to a good design of photovoltaic systems, as they will directly affect the performance and capture of solar energy of the installation .

It is true that it is not necessary to comply with a single and strict inclination and orientation, because as we have seen, slight deviations have practically no impact on the uptake.

You can find all the photovoltaic equipment that we supply, such as all kinds of solar panels  , inverters and other components on our website.