• GPC Logo DC Clear
  • Frequently Asked Questions

  • We support renewable energy and partner with our customers to ensure safe and reliable interconnection of renewable energy into the electric grid.

    In the District of Columbia, you may have questions as you consider applying for small generator interconnections and net energy metering. We have compiled a list of a few frequently asked questions that may be helpful. If you have any further questions, contact our Green Power Connection™ team. You can also download a PDF version of the FAQs.

    Net Energy Metering FAQs

    What is Net Energy Metering?

    Customers who generate their own electricity with renewable energy sources can interconnect with the electric grid and receive bill credits for excess generation. A special net-capable meter measures the energy a customer uses off the grid and the excess generation the renewable system provides onto the grid, and calculates the difference or “net.” 

    What is Green Power Connection? 

    Green Power Connection (GPC) is our process for facilitating small generator and NEM interconnection requests.  Our dedicated team of consultants and account coordinators manage the customer’s experience – from processing applications to resolving issues – for residential and smaller commercial interconnection projects.

    What is a net-capable meter?

    A net-capable meter measures energy that flows in both directions between the customer-generator and the electric grid. 

    What technologies qualify for net energy metering?

    In the District, small generator technologies that qualify for NEM and interconnecting with our system include solar (photovoltaic or “PV”), wind, biomass, anaerobic digestion, geothermal electric, fuel cells using renewable sources, and cogeneration and microturbines. 

    When do I start the interconnection application process?

    Prior to installing and operating a generator system, you must apply and receive the utility’s written approval. District of Columbia customers refer to the Small Generator Interconnection Application Checklist in the District of Columbia or the Net Energy Metering and Small Generator Interconnection Application Checklist in the District of Columbia.

    Do I have to interconnect my renewable generating system to the grid?

    No. But if you wish to export excess generation to the grid and receive bill credits, the system must be interconnected and include a utility-supplied, net-capable meter. You must apply for this interconnection.

    Does the net-capable meter measure total generation?

    No. Generation occurs on the customer side of the meter. Any energy generated is first fed inside the premise for use by the appliances, electronics, lights, etc. The meter measures only the excess energy that is fed onto the grid. 

    How does the meter show when energy is fed or received?

    A smart net energy meter has dashes under the display that move in the direction of the energy flow.  When the dashes move from left to right, energy is flowing from the grid to the customer’s premise. When the dashes move from right to left, energy is flowing from the customer to the grid.

    Application and System FAQs

    How do I start the application review process?

    Prior to installing and operating a generating system, you must apply and receive the utility’s approval. Review the Net Energy Metering and Small Generator Interconnection Application Checklist.

    How long does the interconnection application process take?

    From the day you or your contractor first submits a complete application to the day Pepco issues your final Authorization to Operate, including the time it takes your contractor to install the solar generating system, the interconnection process in the District of Columbia takes approximately 80 business days. Click here to download a printable PDF of the application steps and timeline.

    How do I apply for interconnection?

    Review the detailed interconnection application process. Generally, but not always, installation contractors complete and submit the application on behalf of their clients. When you’re ready to begin, you can jump right to the online application portal

    What if I have questions while completing the application?

    If you have questions about your application, you can ask them at any time directly in the portal by clicking on the question mark icon in the left navigation.

    How do I approve my application? 

    Pepco will send you an email when your application is ready for your review and approval. This handy Customer Approval of NEM Application guide describes the steps. You can begin your review and approval by clicking on the link in Pepco’s email to you, or by entering the portal.

    How is my application fee determined?

    Fees are established by our regulators, and vary according to the generator system’s nameplate capacity. Review the application fees in the District. Our online interconnection application system automatically calculates any required fees, based on jurisdiction, system size and application level.

    When do I pay my application fee?

    After your interconnection application has been entered into the online portal, the system automatically determines if an application fee is required and calculates the required fee, based on the jurisdiction, system size, and application level.  The online system automatically creates and emails an invoice to the contractor or customer.

    How do I pay my application fee?

    The contractor pays the invoice by credit card or bank transfer either through Speedpay or by mailing in a check with the invoice. 

    Why could my interconnection application be delayed or denied?

    Applications will be delayed if required information is incomplete or missing, or documents are unsigned. In some regions, our utility may not have an open circuit, making net metering interconnection unavailable. In the District of Columbia, we currently do not have any restricted circuits. For more details contact our GPC team.

    How is the size of the renewable system determined?

    Add up the total energy consumption (in kWh) as shown on your last 12 Pepco bills. Divide that sum by 1,200. The result is the maximum inverter nameplate rating you can install. We use the formula 12-month kWh usage / 1,200 = maximum kW inverter rating, to comply with District of Columbia rules, meet all or part of your electrical needs, and follow our regulatory requirements.

    What is the maximum size of a small generator system I can install?

    Customers who install a renewable generating system can offset all or part of the energy they use from Pepco. Interconnection capacity restrictions vary among states and jurisdictions. In the District of Columbia, the system capacity can be up to 100% of your 12-month historical energy consumption.

    How can I see how much energy my system generates?

    Your system's installer can provide details on obtaining a generation monitoring device compatible with your system.

    What standards does Pepco apply when approving inverters and system components for interconnection?  

    Institute of Electrical and Electronics Engineers (IEEE) Standard 1547 provides the criteria and requirements for interconnecting small generator equipment to the electric grid. Underwriters Laboratory (UL) Standard 1741 sets the requirements for the inverters and charge controllers used in photovoltaic (PV) power systems. In most cases, inverters that comply with IEEE 1547 and UL 1741 will be acceptable for interconnection. The equipment on the Acceptable Inverters List  has been accepted for use in other small generator interconnection project requests.

    Will my system generate power during a utility power outage?

    No. If your system is interconnected to the grid, do not attempt to use it during a power outage. The electric inverter immediately shuts down to prevent power from back-feeding to the grid and injuring nearby utility workers. The inverter is the component that converts direct current (DC) power from the renewable generator into alternating current (AC) power used at your premise.  

    If I have new construction project that will incorporate a small generator system, can I interconnect?

    Yes. For a facility that is under construction and requires electricity, you will need to set up electric service prior to installing the generation system. Without any historical energy consumption data, the interconnection application will require a proposed energy usage calculator.

    I want to install a large generation facility and sell power directly to the grid.  Do I work with the GPC team?

    Another department within Pepco administers these large PJM power purchase agreements. The GPC team will be glad to refer you to that department.

    Are customers with third-party energy suppliers eligible?

    Yes.

    NEM Billing FAQs

    Now that my system is interconnected, what can I expect on my Pepco bills? 

    After interconnecting a renewable generating system to the electric grid, many customers anticipate very low utility bills – or no bills at all.  You may have questions about how NEM will affect your Pepco bills.  This printable Net Energy Metering and Your Pepco Bill FAQ answers most questions.  If you still have others, please call 866-634-6977.  

    What is a Solar Renewable Energy Credit (SREC)?

    An SREC is equivalent to one megawatt-hour (MWh) of electricity derived from an eligible solar resource. Electricity suppliers must purchase SRECs in order to meet compliance obligations under the law. For more information, visit energy.gov.

    Other FAQs

    Are there other factors to consider?

    Yes. Electric generation from solar sources can fluctuate as a result of several factors — clouds, darkness, and dirty panels all limit generation. Your renewable system may not generate enough energy to meet all of your electrical needs. Prior to installation, understand how your system will operate under varying conditions, and how these conditions can impact your utility bill.  

    Can I operate my generation facility prior to receiving the final written Authorization to Operate?

    Pepco prohibits the interconnection of generation facilities to the electric grid without our written approval. Operating an unauthorized small generator system tied to our grid can:

    • Endanger Pepco workers, who will not have a record of the system
    • Pose a safety risk to the customer, system components, facility, and nearby general public
    • Cause voltage over overload problems on the grid, preventing safe and reliable electric service
    • Lead to a cease-and-desist notification
    • Lead to disconnection of electric service 

    How can you ensure your system is authorized?


    Can you recommend a reputable installer?

    No. We recommend you research and consult with an installer or contractor by using publically available resources.  If you decide to work with a contractor, you are responsible to ensure they are using the appropriate forms, fees, and documentation throughout the interconnection process.