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  • Estimate Your Solar Needs

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

    Some premises are better suited to a rooftop solar array than others.  Our WattPlan® service will help you estimate the electricity a system might generate at your premise and how much you might save each year on your electric bills.  Enter your address and basic information from your electric bills to receive your personalized solar estimate. 

    Another step in evaluating your solar array options is to understand Delaware renewable generating system sizing regulations.  While interconnection capacity regulations vary among states, Delaware customers can offset all or part of the energy they use from Delmarva Power.  In Delaware, the system capacity can be up to 110% of your annual historical energy consumption. To determine the maximum kV inverter rating of your proposed solar system, take the average of the total energy consumption (in kWh) for the two 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 Delaware rules.

    To view your historical usage or to authorize one or more solar contractors to access your historical usage data, log in to My Account. Choose Manage My Account and then Authorize Contractor Access to grant contractor access to view your usage data. If you do not have a My Account login, you can register here. For further information on the steps to take to authorize contractor access to your historical energy usage, visit the Request Customer Usage page.