Inverter sizing factor

[1Plasmon]

Hello!

Let's assume, inverter sizing factor is defined as:

Inverter Sizing Factor, Cinv = Array STC power / Inverter AC nominal rating

Can anyone tell me how does this factor vary with the POA irradiance and PV array STC size?

Thanks

A.

[cnrikio]

With varying irradiance, the factor you defined would not change. Since array STC power would not go up or down with the external condition changed, and the same for inverter AC nominal rating as well. But if the array STC size changed, the factor would be different accordingly.

The factor is a value as the rule of thumb, but it is not recommended to size the inverter accroding to it, since ambient temperature, module orientation and other parameters need to be considered when doing specific system designing.

[1Plasmon]

Great! Thank you.

Since that time I studied some approaches about how to quantify SF (sizing factor) as related to the PV Array STC power. I understand this is an optimization problem that needs to be run for influencing factors like: orientation, irradiance and temperature profiles through the year, assuming one is looking at a specific site.

[André Mermoud]

Please have a look on the FAQ What is the basic concept of Inverter sizig ?.

And also use the graph when pressing the button "Show optimization" in the System definition dialog.