How can the "inverter loss during operation (efficiency)" lead to increased energy output?

[sirihar]

Hi,

I am working on a grid connected system in version 6.19.

In some cases, I end up with a simulation report where the "inverter loss during operation (efficiency)" has a positive value, meaning it increases the overall efficiency of the system. From the tables I can generate after the simulation, it seems like this "input" of energy due to "inverter loss" occurs in months where the modules are heavily affected by partial shading.

Can somebody please explain me how the "inverter loss" can increase the overall effiency? How is the "inverter loss during operation" calculated? Has it something to do with a reduction in loss due to an inverter which is able to perform global peak MPPT? Has it in general something to do with shading losses? Or is it a bug?

I have really tried to twist my head and search in the help-manu as well in the forum, but I cannot find any answers. I would really appreciate any helpful comments.

Best regards,

Siri

[André Mermoud]

Don't try to find an explanation. This is indeed a bug. I big bug, that I have never seen.

Please check the Efficiency curve in your Inverter's definitions.

However this should not arise of course. Please send me your whole project, using "Files" / "Export projects" in the main menu.

(andre.mermoud@pvsyst.com)