If You’re Making Energy, We’d Like to Take Some Off Your Hands

The Net Energy Metering program is a win-win situation: if you’re generating your own energy from a renewable fuel source and you make more than you consume, you’ll earn bill credits. Then we'll have clean energy to supply to other customers.

And since there will be times when you can’t make all the energy you use, that bill credit covers the energy you get from us.

On April 27, 2018, the California Public Utilities Commission issued Resolution E- 4920 (E-4920) approving the incorporation of the Reactive Power Priority (RPP) requirement for Smart Inverters into Rule 21 Section Hh.2.i & j.  The Resolution orders the new requirement to become effective for new interconnection requests submitted on and after July 26, 2018.

Click here to view the current list of certified inverters that have been approved for use in SDG&E’s service territory.  If you are a solar installer or an inverter manufacturer and would like to have a certified inverter added to the list, please refer to the following information and instructions. 

To ensure the new requirement is properly implemented, it is necessary to clarify the terminology used to describe the RPP function in the UL1741 SA certification testing process and the terminology used in E-4920.  These clarifications, as well as some additional clarifying information, are as follows:

  1. The term “Real Power” used in E-4920 shall be considered synonymous with the term “Active Power” used in UL-1741 SA and IEEE 1547 (2018).
  2. Inverters must produce the required levels of Reactive Power at all Active Power levels from 20% -100% of Active Power nameplate rating.
  3. Inverters capable of producing the required levels of Reactive Power without reducing Active Power, i.e. no power priority, are considered to be in compliance with the RPP requirements contained in E-4920. 
  4. Inverters are permitted to reduce Active Power in order to produce the required levels of reactive power when operating at their apparent power limit, (a requirement for RPP).
  5. Inverters shall not reduce reactive power below the required limits in order to maintain Active Power output when operating at their apparent power limits, i.e. Active Power Priority (APP)
  6. Inverters are not required to support multiple reactive power modes.  For qualified inverters, the NRTL must document that the inverter only operates in RPP mode and is not capable of operating in APP mode.
  7. Where the inverter supports multiple reactive modes, such modes shall be identified using the terminology contained in the certification information from the NRTL conducting the evaluation.  The NRTL must confirm that each of the multiple modes has been evaluated.
  8. Where terminology used in NRTL certification information deviates from the terms Active Power Priority or Reactive Power Priority as defined in resolution E-4920, the NRTL must provide an explanation of the terms used and how those terms provide equivalency to those used in E-4920.
  9. Inverters are required to be evaluated using the requirements and test procedures contained in UL 1741 SA13 - Volt/VAr Mode (Q(V)).
  10. Inverters are required to be evaluated using the requirements and test procedures contained in UL1741 SA8 Anti-Islanding Protection - Unintentional Islanding with Grid Support Functions Enabled.  NRTLs must certify the Unintentional Islanding testing in SA8 has been performed under the worst-case condition created by any of the power priority modes by including the inverter part numbers in the table below.

In order to allow the interconnection of Smart Inverters to the CA Utilities’ distribution grids, Manufacturers are required to demonstrate that their UL1741 SA Smart Inverters were properly evaluated under the new requirements established in E-4920, as described above.

In order to have a certified inverter added to the list of approved devices, manufacturers must answer the questions below for each inverter that has been certified for UL1741 SA compliance by the NRTL.  The information must be accompanied by a letter, certifying compliance from the NRTL, using the NRTL’s letterhead and sent to the CA Utilities (email addresses provided below).

Pacific Gas and Electric:  [email protected]

San Diego Gas and Electric: [email protected]

Question Description Direction for NRTL
1 Is the product capable of providing the required reactive power for the volt/var curve function at all active power levels without derating active power?
(Y or N) (Active Power = 20 - 100%)
A "Yes response meets the intent of the Resolution and Question #2 and #3 do not need to be answered
2 Was the volt/var curve tested with reactive power priority enabled? (Y or N) A "Yes" response meets the requirements of the Resolution and Question #1 does not need to be answered
3 Was the volt/var curve tested with active power priority enabled? (Y, N, or N/A) An "N/A" response indicates active power priority is not an option for the inverter. A "Yes" indicates that the inverter must be programmed with the correct profile in the final installation

Please submit your information in an excel file using the format in this example:

Inverter Manufacturer Name

Inverter Model Number

Question #1 (Y/N)

Question #2 (Y/N)

Question #3 (Y/N)





This note is an update to the note we sent on September 8, 2017, as a reminder that after 11:59 p.m. on September 8, all interconnection applications for inverter-based systems must use smart inverter technology.  In our previous note we incorrectly stated that only those inverters with the [SI1]designation in the model number will be accepted.

We sincerely apologize for any confusion this has caused.  Here is the corrected information:

Please visit http://gosolarcalifornia.org/equipment/inverters.php and click on the “Inverters List – Full Data” for the comprehensive list of inverters. Only those inverters with a certification date identified in column G will be approved.  For example, ABB PVI-3.0-OUTD-S-US-Z-M-A (240V) [SI1] is an approved smart inverter since it has a certification date of 09/09/2017 listed in column G.

For a detailed description of the smart inverter requirements, please refer to section Hh. of SDG&E’s Electric Rule 21.  If you have questions, please feel free to give Ken Parks a call at (858) 636-5581.

Program Requirements

Any SDG&E customer who generates at least some of their electricity with a renewable energy source is eligible to participate.

There are two primary eligibility requirements for NEM:

  • Your electricity generating system must be fueled by solar, wind, or a other renewable source. Other renewable fuels include, but are not limited to, biomass, geothermal and small hydro.

  • Your system must comply with the rules and regulations for interconnecting customer-owned generation to SDG&E’s grid.

Learn more about gas and electric standards

There is a state-mandated cap on NEM and the rules for customers with systems connected before the NEM cap was met are slightly different than the rules for customers with systems connected afterwards. 

Customers with authorized interconnections established before the NEM cap was reached are subject to the provisions of Schedule NEM. NEM customers are grandfathered under NEM rules for 20 years from their original interconnection date.  Refer to the Transition Process section of Schedule NEM for details.

On June 29, 2016, the NEM cap was reached in SDG&E’s service area. Going forward, interconnection applications for net energy metering are governed by the rules of the NEM Successor Tariff (Schedule NEM-ST or NEM-ST).

  • Customers with eligible systems that are 1 megawatt (MW) or smaller will be charged a $132 interconnection fee.
  • Customers with eligible systems larger than 1 MW will be charged the standard $800 interconnection fee and will be responsible for paying the costs of applicable transmission and/or distribution system upgrades that may be required.
  • Customers participating in the Single-family Affordable Solar Housing Program do not have to pay an interconnection fee.
  • NEM-ST customers will be billed non-bypassable charges (NBCs) on the net kilowatt-hours (kWh) delivered by SDG&E during each metered interval.
  • NBCs are made up of the following rate components:
    • Public Purpose Programs (PPP) charge
    • Nuclear Decommissioning (ND) charge
    • Competition Transition Charge (CTC)
    • Department of Water Resources Bond Charge (DWR-BC)
  • In the event an existing Schedule NEM customer increases NEM generator system size in excess of the following limitations, the customer will be responsible for paying NBCs on 100% of the net kWh delivered by SDG&E during each metered interval:
    • Systems that are 10 kilowatts (kW) or smaller can be increased by no more than 1 kW.
    • Systems that are larger than 10 kW can be increased by no more than 10% of the existing system size.
  • NEM-ST customers receiving service under a multiple tariff facility arrangement will also be billed NBCs on 100% of the net kWh delivered by SDG&E during each metered interval.
  • NBCs cannot be avoided by installing a generation output meter.
  • SDG&E customers who begin service under NEM-ST on or after the initial effective date of the tariff and for up to 120 days after the initial effective date of SDG&E’s General Rate Case Phase 2 (GRC P2) TOU rates can choose to receive service under an optional TOU rate or the existing tiered rate.
  • SDG&E customers can continue to receive service under their current rate for up to five years after they received permission to operate their system.
  • SDG&E customers who begin service under NEM-ST after 120 days from the initial effective date of the GRC P2 TOU rates must be on a TOU rate.

All NEM-ST applicants must certify that a warranty of at least 10 years is provided for on all system equipment and installation

Eligible customers can continue to receive service under NEM-ST for up to 20 years from the original year they received authorization to operate their systems.  The following criteria, which are not mutually exclusive, will apply in the event NEM-ST is closed to new customers:

  • Customers whose system capacity is 10 kW or smaller can increase the capacity by up to 1 kW.
  • Customers whose system capacity is larger than 10 kW can increase capacity by up to 10% of the original capacity.
  • In the event a system is transferred to a new owner, the new owner will maintain the 20-year transition period so long as the system remains eligible for service under NEM-ST at the same location.
  • A paired energy storage system will be subject to the same transition period as the renewable facility that it is paired with. 
  • The virtual NEM successor tariff, Schedule NEM-V-ST, allows customers who are connected to different service delivery points on the same property to participate as Qualified Customers under the tariff.

NEM rates

For homeowners, the bill credits you earn and the electricity you consume (usage not covered by bill credits) are based on the electric or billing rate you select when you join the program. You can opt for the NEM billing rate or elect to stay with your residential rate.  Click below to do a self-analysis of your regular energy usage to select the rate that's right for you.

Learn more

Your NEM bill

Now that you're generating part or all of your own power needs, your billing will change to reflect this. You should expect to receive two bills from SDG&E; one bill for the meter your renewable generator is associated with and another bill for your gas meter and other electricity meters, if you have any. Click below for the specifics.

How You’re Billed with NEM

Billing FAQs

Understanding Your NEM Statement

NEM Programs and Benefits

Apply for NEM

1In its decision adopting NEM-ST, the California Public Utilities Commission (CPUC) established a requirement that all residential customers receiving service under NEM-ST must be billed on a TOU rate.  Prior to that decision, SDG&E submitted a proposal to the CPUC in its most recent GRC P2 Application that will, if approved, result in a change to the current TOU billing periods.  Because of this, SDG&E asked for and received approval from the CPUC to delay the implementation of mandatory TOU rates for residential NEM-ST customers until the GRC P2 rates become effective.   

NEM Documents

Everything you and your contractor will need to know to get you setup on our NEM program.

Learn More