How to use the PVGIS tool, European Union, to compare fixed structure and single-axis solar trackers:

1-First, we will select the coordinates we want in PVGIS, in this example, we’ll select a plot of land in Sant Fruitós where a solar plant is already located. We’ll select “grid-connected,” as this option is for a fixed structure (rooftop installations also work), and we’ll set it to “optimize tilt,” since the fixed structure can be manufactured at any angle. We click “View results,” and we’ll see something like this:

2-Let’s look at the results; they’re useful: “Tilt angle [°]” which in this case is optimal at 38°, and “Annual PV production [kWh]” which in this case is 1558.23 kWh. Since we defaulted to a power of only one kW installed, this means we have a production of 1558.23 kWh/kW. We also have a graph showing production by month. You can download the PDF if you wish.

3-Secondly, we will compare it to what a single-axis tracking system could generate: we will select “PV with tracking,” since this option is for trackers, and then select “inclinated axis” with a tilt of 0º if the terrain is flat, or the corresponding tilt if the terrain slopes south. In our case, the tracker has this length (0º inclination), and the axis moves fr om east to west. We click “View results,” and we will see something like this:

4-Let’s look at the results; they’re useful: the “Annual PV Production [kWh]:” which in this case is 1830.23 kWh. Since we left the default installed capacity at 1 kW, this means we have a production of 1830.23 kWh/kW. We also have a graph showing production by month. You can download the PDF if you wish.

Finally, we see that the tracker provides an extra 17.5% of production in this specific example just because of the tracking system, but this can vary depending on the location and whether the terrain is sloped, as well as the part of the world. Then, the performance of bifacial panels would also be added, which in the case of trackers is much higher than in a fixed structure.