MPitor

[herminator]

Dears,

I have recently upgraded my PVSYST to 7.3 Recalculation of the same project variant calculated before in 7.2.21 provided totally different yields. Need to add that former calculation is more trustworthy. Does anybody has similar bug expierience?

 

Screeenshots depicting the difference are attached. Difference is huge. Please look at the system power distribution.

1804 - PVSYST 7.2

1478 - PVSYST 7.3

M

[André Mermoud]

Yes sorry.

Yes, sorry. There is indeed an important bug in the version 7.3.1. When using the irradiance optimization option for trackers, the phi angles are not calculated correctly.

A workaround is to revert to the usual “astronomic” calculation, which will probably be more compatible with your actual control system on the field.

In the “Orientation” dialog, you should uncheck the option:

This usually gives a difference inferior to  1%

This issue has been fixed and the correction will be made available in the version 7.3.2.

[herminator]

Thank you. Thus I wont use Irradiance optimization for a while.

BR MP