Shading losses applied after calculation of GPOA

[jonipa]

Hello,

Taking a look to the project simulation losses graph and main results with which the PR is calculated some questions arise regarding GlobInc parameter.

While in the main resutls table I get a yearly value of 2483,9 kWh/m2.

The losses graph shows a value of 1849+34.4%=2485 kWh/m2. I understand it could be assumed as the same value though it is not exact.

But the main question involves the next losses on the graph such as far and near shadings, reflection, diffuse, etc. They are applied AFTER defining GlobInc value but in reality (on-site) what we will be measuring as GlobInc will be a value in which shading losses, reflection, diffuse irradiance, etc. are already applied.

To my understanding this has a big effect on the Performance Ratio value given by PVSyst as, in my opinion, the value of radiation used in the PR formula should be closer to the "Effective irradiation on collectors" value rather than "Global incident in coll. plane". Could anyone share their thoughts on this? 

Thank you!