The excitement and satisfaction of seeing those low electricity bills after the commissioning of a solar project can give way to shock and fear when you receive the first annual net energy metering (NEM) true-up bill. You might find yourself wondering why this bill is so high compared to the other low monthly bills you’ve seen. This true-up bill can leave you wondering if the system is working, whether you are even saving money, or if the investment in solar was worth it.

An energy partner like TerraVerde’s Asset Management Team can help answer those questions and provide you with the transparent picture of your solar project’s savings performance.

READING YOUR NEM BILL

Once your meter is on an NEM tariff, your typical monthly bill will be made up of service charges and demand charges (if applicable). All energy charges, the charges that are calculated on a per kWh basis, will be tracked and paid on an annual basis, reflected in your annual True-Up Bill. PG&E customers on NEM will receive a separate Detail of Bill (or “white bill”) that breaks down the specific bill components that make up each monthly bill. The following examples are excerpts from PG&E Detail of Bills.

This example from a PG&E customer on the A6 rate shows that their energy use resulted in charges of $25.46 as a monthly service charge and $4,451.12 for their electricity use.

The important thing to note is that the energy charge was not actually billed that month, the customer only paid $25.46. The current month energy charge was added to the cumulative energy charge total. These cumulative energy charges, which can include bill credits if the value of solar exports is greater than the value of electricity used, will be paid annually with a true-up bill.

Below is an energy true-up example table from PG&E’s Bill Detail. You will notice in the “Energy Charges / Credits” column that each month’s energy charges varied from -$1,095.05 (in August 2020 with high solar exports) to $4,752.17 (in February 2021, where the customer used more electricity than their solar produced). The total in this column reflects the cumulative energy charges as discussed above. At the end of the true-up period, the total amount owed for energy charges for the year was $26,321.78.

BILL SHOCK

The following table shows the actual bills paid for a different customer each month during an annual true-up cycle.

The customer may grow accustomed to those $35 bills (only service charges) and be surprised when they suddenly get their true-up bill for over $19,000! But as we saw previously, the large true-up bill is made up of energy charges from the previous 12 months. In this case it also includes credits from the first four months when their solar PV system generated more electricity than they used.

DID WE SAVE MONEY?

Given the complexities of post-solar electricity bills, the variability of solar production, and the fluctuations in energy usage at various facilities, it can be very difficult for customers to know whether they are saving what they were expecting from their solar projects. TerraVerde Energy’s Asset Management Services program provides clients with transparent, actionable reporting on:

• Actual vs. expected solar performance
• Actual vs. expected energy usage
• Actual vs. expected financial savings

Our reporting is enabled by our proprietary software platform, SolarShadow, which enables us to accurately simulate what your electricity bills would have been without your solar project, and show the actual savings being delivered.

To learn more about how TerraVerde’s Asset Management program can help you get the most out of your solar and battery projects, write to us at hello@terraverde.energy.