Net Meter vs Non-Net Meter for Tiered Rates

Using Tiered Rate structure, specifically for Southern California Edison, toggling the Net Meter function changes the Electricity Cost without System dramatically. Electricity cost with net metering is almost double of non-net metering. The modeled load is the actual load downloaded from SCE for a specific residence. The non-net metered electricity cost match closer to the actual annual electricity bill from SCE. Why is the net-metered electricity cost so much higher and not reflective of the actual bill?

Dear Stanley,

When you run the residential or commercial financial model with net metering, SAM calculates the electricity bill on a monthly basis, accounting for any reduction in the bill due to the renewable energy system. The renewable energy system's generation effectively reduces the total monthly bill, with excess credits rolled over to the next month on either a kWh or dollar basis.

Without net metering, electricity sales to and purchases from the grid happen on an hourly basis at prices determined by the electricity rate structure.

Most utilities in the United States use electricity rates with net metering, so in your case, I would expect SAM results with net metering to more closely match the actual bill than without net metering.

Best regards,
Paul.