Error "Info: parameter Pitch was set, Warning: parameter Pitch did not change, The GCR used for the backtracking algorithm (0.675) differs from ..."

[Sunny Day]

I am attempting to run batch simulations where the pitch is varied (screenshots are attached).

The tracker pitch in the shading scene is 3m. The following error is being displayed for runs where the simulated pitch differs from 3m:

"Info: parameter Pitch was set, Warning: parameter Pitch did not change, The GCR used for the backtracking algorithm (0.675) differs from the average GCR (0.289)."

The following error is being displayed for runs where the simulated pitch is 3m:

"Warning: parameter Pitch did not change"

I ran some tests in batch mode and in single simulation mode and a quick comparison indicated the results were the same i.e. the error messages returned when running in batch mode are bogus. Is anyone able to confirm that the error messages are bogus?

[Michele Oliosi]

You still have the column "Pitch" in your batch file. Since there are only trackers in the scene, the pitch cannot be changed, which triggers the warning. What matters is the other column, "Trackers pitch EW". I would recommend removing the "Pitch column" and rerunning the batch.

Note also that you should be mindful of how the backtracking parameters were set (3D scene > Tools > Backtracking management):


Here the mode is manual (automatic unchecked). This means that if the batch mode changes the pitch, the backtracking algorithm will not follow, and the yield may decrease (either from being suboptimally oriented or from shadings).

Instead if you choose "Automatic", then the backtracking will adapt to the changes from the batch.