Solar PV excess generation issue

Hi,
I am having an issue with excess solar PV generation where the system reports zero excess generation for all times of the year no matter how large the solar PV system is.
The system has a 15kW grid interconnection limit and is set for net billing with buy and sell rates.
To check there is enough excess electricity generation available the system was oversized and has a 27% grid interconnection loss rate so I am confused how it can have such a high grid interconnection loss but never produce any excess electricity.
I have attached the SAM file and any help on this would be greatly appreciated.

Kind regards,

Craig

Hi Craig,

Sorry, the variable names here are a little misleading.

The monthly "Excess generation" output variable only applies to the net metering options that calculate excess generation as the difference between the total monthly generation and total monthly load. For the net billing and buy all / sell all metering options, SAM sets excess generation to zero.

The net billing options calculate excess generation on a time step basis. The monthly "Net billing credit" output variable applies to the net billing options. The excess generation in this case is the "Electricity to grid from system" in the lifetime hourly (or subhourly) results. You can verify that by displaying that variable along with "Lifetime electricity load" and "System power generated:" You should see that To Grid = Power Generated - Load.

Some of this is explained in the "Electricity Bill Results" topic of Help (find it under "Electricity Rates and Load" in the table of contents). I will make some revisions to make this more clear.

Thanks,
Paul.