We support renewable energy and partner with our customers to ensure safe and reliable interconnection of renewable energy into the electric grid.
We understand that you may have questions as you consider applying for small generator interconnections. 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.
What is Net Energy Metering (NEM)?
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 Delaware, eligible renewable technologies include solar (photovoltaic or “PV”), wind, hydro-electric, fuel cell, and organic anaerobic digestion.
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. For more details, refer to the Net Energy Metering and Small Generator Interconnection Application Checklist.
Do I have to interconnect my generator system to the grid?
Most customers install renewable generator systems to reduce their use of utility-supplied electricity. For these behind-the-meter systems to be able to draw energy off the grid when needed, the system must be interconnected to 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 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.
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. When you're ready to begin, you can jump right to the online application portal.
How long does the interconnection application process take?
From the day you or your contractor first submits a complete application to the day Delmarva Power issues your final Authorization to Operate, including the time it takes your contractor to install the solar generating system, the interconnection application process in Delaware takes approximately 77 business days. Click here to download a printable PDF of the application timeline.
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?
Delmarva Power 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 Delmarva Power’s email to you, or by entering the
How is my application fee determined?
Fees are established by the Delaware Public Service Commission, and vary according to the generator system’s nameplate capacity. Our online interconnection application system automatically calculates any required fees, based on jurisdiction, system size and application level. See our table of the fees for Delaware.
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. This fee invoice must be paid before Delmarva Power can issue the Authorization to Operate your renewable generator system.
How do I pay my application fee?
The contractor pays the invoice either by credit card or bank transfer through
Speedpay or by mailing in a check with the invoice.
Why could my interconnection application be delayed or denied?
Applications are 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. For more details contact our GPC team.
How is the size of the renewable system determined?
Take the average of the total energy use for the 2 previous 12-month periods, as shown on your Delmarva Power bills. Divide that average by 1,200. Multiply that total by 1.1. The result is the maximum inverter nameplate rating you can install. We use the formula [(average of the 2 previous 12-month periods' kWh usage)/ 1,200] x 1.1 = maximum kW inverter rating, to comply with state 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 Delmarva Power. Interconnection capacity restrictions vary among states and jurisdictions. In Delaware, the system capacity can be up to 110% of your 12-month historical energy consumption.
How can I see how much energy my system generates?
The installer of your renewable system can provide details on obtaining a generation monitoring device compatible with your system.
What standards does Delmarva 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?
For safety reasons, the system's inverter tied to the grid will shut down automatically with an outage. The inverter coverts direct current (DC) power from the renewable generator into alternating current (AC) power used at your premise. Only systems designed to operate independently during an outage will be able to operate. A system designed in this fashion must be clearly identified on the interconnection application and agreement. A single-line diagram showing the equipment and controls necessary to operate safely when isolated must accompany the application.
If I have a 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?
No. Another department within Delmarva Power administers these large wholesale power purchase agreements. The GPC team will be glad to refer you to that department.
How is excess generation shown on my utility bill?
Customers in Delaware will see negative energy consumption in the Details of Your Energy Charges section of the bill, showing excess carryover history. The excess is carried over month to month until used or until the customer’s anniversary pay out.
Why does my bill still show charges, if I had excess generation credits?
Customer service charges apply to all bills, regardless of energy charges or excess generation credits. If the service charges are more than the generation credits your account would show a balance due.
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
What is the difference between monthly data and interval data?
Monthly data is the total monthly kilowatt hours (kWh) for which you are billed. Interval data is the hourly kWh reported by your AMI meter.
What is Green Button?
The Green Button initiative is an industry-led effort that responds to a White House call-to-action to provide utility customers with easy and secure access to their interval usage information. A Green Button interval data file can be read with an application that supports Green Button standard.
When I request historical data, what time frame of data will I receive?
You will receive up to 24 months of data.
On the contractor’s NEM Dashboard, why does Pending status only show the customer’s account number?
It is a security standard that customer name and address not be visible until authorization to download customer data has been approved.
How can I contact Delmarva Power regarding my solar request status?
Please contact us at firstname.lastname@example.org.
Why isn’t my organization listed in the list of contractors found in my customer’s/client’s My Account?
Contractors who have created logins for Green Power Connection's online net energy metering application system are listed alphabetically in the Manage My Account section of My Account. If your organization is not listed, a contractor login has not been created and your organization will not appear in My Account. Contractors cannot be approved via My Account until a login has been created for Green Power Connection's online net energy metering application system. Contractors can register here.
Why won’t my attachment load to the website?
Your attached file may not be the correct file type. Only Adobe Acrobat (PDF) documents and image files (JPG, PNG, GIF) are accepted.
Why does the interval format give more current results than the monthly option?
Monthly data is shown by billing month. Interval data is shown daily, and may include data up to the day before your download.
When will authorization to download a customer’s data expire?
Access will expire one year from the signature date on the authorization form or one year from the day the customer authorizes your organization in My Account.
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?
No. The Delaware Public Service Commission 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:
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, it is your responsibility to ensure they are using the applicable forms, fees, and documentation throughout the interconnection process.