Behind the meter modeling

How is the best way to model a grid-tied behind the meter only installation without any net-metering, using an avoided cost for all excess production? Is it simply choosing net-metering, inserting a value for excess and not checking roll-over? 

Also, is there a universal way to manually insert a utility company rate?

Thank you 

Hi Dennis,

If the excess generation is calculated by subtracting total monthly generation from total monthly usage, then the "Net energy metering with $ credits" should work. If the excess generation is calculated in each time step (hourly or subhourly), then the "Net billing" option is the one you want. You can find descriptions of all of the metering and billing options in the Help topic for the Electricity Rates page.

For utility rate data, SAM uses the same format as the OpenEI Utility Rate Database ( openei.org/wiki/Utility_Rate_Database ). If the rate you are modeling is in the database, you can use the Search for Rates button on the Electricity Rates page in SAM to download the data and automatically populate the Electricity Rates page inputs. Otherwise, you can enter the rate data by hand and use the Save Rate to File button to save the data to a file on your computer.

Best regards,
Paul.

Thank you - however, I'm not sure I'm getting the results I anticipate from the model. 
The scenario I'm trying to model (for educational purposes) is one where the solar system offsets usage behind the meter, valued at retail, and any excess is compensated at avoided cost. If I modify the sell price in SAM, it seems to assume ALL solar is sold back at that rate, not just excess. However if I use net-metering option, and assign an excess value, it assumes a monthly true-up, which is not the case when the utility does no net-metering.   
Is there a way to assign excess production only a separate rate hourly. Maybe I'm misinterpreting the results.

Hi Dennis,

Either the "net billing" or "net energy metering with $" option (not "net energy metering") should do what you expect. The net billing option calculates excess generation on an hourly (or subhourly) basis and reports the dollar value of the credit as "Net billing credit" in the monthly results (see them on the Data Tables tab on the Results page), and net energy metering with $ calculates excess generation on a monthly basis and reports the value of the credit as "Net metering credit."

Best regards,
Paul.