About the Energy Efficiency Investment Fund

This is a collection of questions and answers about the Delaware Energy Efficiency Investment Fund (EEIF).

If you have questions on program eligibility, the application process or need help completing the application, email or call 802-482-5645. Please refer to the program guidelines for more details for the specific pathway requirements and full list of eligible measures.

What is the Energy Efficiency Investment Fund?

The Energy Efficiency Investment Fund (EEIF) is a rebate program that provides financial assistance to Delaware non-residential entities (e.g. commercial, industrial, non-profits, etc.) seeking to replace aging, inefficient equipment with energy efficient alternatives.

The primary purpose of EEIF is to improve the energy efficiency of businesses by reducing energy consumption, maximizing energy savings, and improving environmental performance. Additionally, EEIF encourages businesses to decrease energy use in order to not only curb greenhouse gas emissions, but also ensure that the program remains aligned with the sustainability and energy conservation goals outlined in Delaware’s Climate Action Plan.

Who can participate in the EEIF program?

The EEIF Program is available to all non-residential, commercial, and industrial entities throughout the State of Delaware who pay the public utility tax (PUT) on their monthly electric/natural gas utility bills. Applicants that do not pay the PUT may be able to receive funds through the Regional Greenhouse Gas Initiative (RGGI) as they become available, though not a guarantee.

What types of projects can receive funding through EEIF?

The EEIF Program offers four primary rebate pathways to Delaware non-residential entities with both existing building and new construction projects.

Prescriptive pathway rebates are for common energy-efficient improvements, such as lighting and lighting control measures, HVAC and water heating equipment, and appliances and food service equipment.

Custom pathway rebates are designed for more complex, non-standard measures that go beyond the equipment funded by Prescriptive rebates. These include, but are not limited to: steam system, building envelope, and chiller and boiler improvements.

Energy Assessment pathway rebates are designed to support both single-purpose and comprehensive energy audits that aid facilities in need of technical evaluations for appropriate, cost-effective energy efficiency improvements, specific to each building’s needs.

Combined Heat and Power (CHP) pathway rebates are ideal for large facilities with high annual hours of operation and high thermal loads. The CHP rebate pathway provides incentives for five CHP systems, including microturbines, reciprocating engines, gas turbines, steam turbines, and fuel cells.

For more information on specific pathway requirements and eligible measures, please refer to the EEIF Program Guidelines and Operational Procedures.

Is there a cap on the amount of funding EEIF can provide for a single project?

Yes. With the exception of energy assessments, the EEIF program will not pay more than 60% of the energy efficiency related project costs for any proposed project up to $250,000 per individual address per calendar year, whichever is less.

For energy assessment rebates, EEIF may award the applicant up to the lesser of (1) 50% of the cost of the energy audit or (2) the maximum award cap of $5,000 for a single-purpose audit or $10,000 for a comprehensive energy audit.

How do I apply for an EEIF grant?

Prior to applying, it is recommended to first review the Program Guidelines and Operational Procedures for your specific rebate pathway’s eligibility and documentation requirements. If you have any questions about the application process or need help completing the application, please email or call 802-484-5645.

To start a new application, visit the Energy Efficiency Application Portal and register as either an applicant or contractor/installer. Once registered, choose the rebate pathway that best suits your proposed project and begin to answer all required application questions and submit all required documents for pre-approval prior to construction. It is important to note that Prescriptive and Energy Assessment project applicants may choose to forego pre-approval and apply for rebate funds within 30 days of the invoice date.

Is there a deadline for submitting applications?

Applications are accepted on a year-round, rolling basis. All rebate awards are subject to funding availability.

How are rebates selected?

All rebates are provided on a first-come, first-serve basis for qualified applicants and projects. Estimated rebate awards can be determined using the energy calculators found in each rebate pathway in the online Energy Efficiency Application Portal. 

Does my project have to be pre-approved?

With the exception of Prescriptive and Energy Assessment projects, all other projects must be pre-approved before equipment is purchased or any work has started. Since there is a limited amount of rebate funds available, funding for your project will be reserved once your application has been pre-approved. Applicants who do not secure pre-approval for their Prescriptive or Energy Assessment projects assume full risk of project ineligibility or lack of funds.

What documentation is required for pre-approval?

Each EEIF rebate pathway has specific required documents listed in the application portal. In general, all projects require:

  • Specification (cut) sheets and model numbers for all equipment
  • Itemized quotes and estimates for all equipment
  • Scope of work
  • Electric and/or natural gas utility bills
  • Completed EEIF online application and energy savings calculator

What documentation is required for final approval?

Each EEIF rebate pathway has specific required documents listed in the application portal. In general, all projects require:

  • Itemized invoices for all equipment and the scope of work
  • Cut sheets with specific model numbers included for all equipment (if changed after pre-approval)
  • Proof of final payment
  • Online registration through the State of Delaware eSupplier Portal
  • Completed eSupplier Information Sheet
  • Installer’s Commercial General Liability Insurance certificate
  • Installer’s business and appropriate professional licenses for the State of Delaware

How long will EEIF funds be reserved for my project?

The length of time funds will be reserved for depends on the rebate pathway:

  • Prescriptive Pathway Reservation Period: 120 days
  • Custom Pathway Reservation Period: 12 months
  • Energy Assessment Pathway Reservation Period: 120 days
  • Combined Heat and Power Pathway Reservation Period: 18 months

Funding will be reserved starting from the date listed on your pre-approval letter. Failure to submit supporting documents needed by the end of your initial reservation date will result in your funds being forfeited. If there are scope changes that affect your project’s completion, we recommend notifying us as you learn of the changes. If your project is running behind, you may request a one-time 60-day extension prior to your expiration date by contacting

When can I expect to receive my rebate following final approval?

Once your project is complete and final approval is issued, you will receive a final approval letter via email. You can expect to receive the rebate check within 10-12 weeks of receiving the letter.

Are there other DNREC programs that I might qualify for?

DNREC offers a series of other energy efficiency and renewable energy programs, many of which can be used to supplement rebates issued through EEIF.

DNREC Programs

The Cool Switch Low Impact Refrigerant Program (Cool Switch) offers rebates to participants seeking to replace existing refrigerants with low global warming potential (GWP) refrigerants or install new systems that use low GWP refrigerants. EEIF participants with qualifying refrigeration projects are encouraged to apply for additional funding through Cool Switch in order to maximize building energy savings and improve environmental performance. For additional information, please visit the Cool Switch website at:

The State Energy Program Revolving Loan Fund (RLF) offers low-interest loans to any Delaware entity pursuing a qualifying energy project. Financing provided through the RLF can be used to support numerous energy efficiency and renewable energy measures, including equipment retrofits and replacements and rooftop and community solar installations. Borrowers can be from the commercial, industrial, non-profit, educational, government, agricultural, and institutional sectors. Loan approval will not compromise an applicant’s EEIF rebate, meaning that loans can be used in combination with a rebate to help cover project costs. To apply for a loan, please fill out the following application form.

The Green Energy Program provides rebates for residential and commercial customers seeking to install renewable energy systems, like solar panels, solar water heaters, geothermal heat pumps, and wind turbines.

The Weatherization Assistance Program helps income-qualified homeowners and renters cut their energy bills by weatherproofing and improving the energy efficiency of their homes. Eligibility is based on both household income and household size, with income eligibility defined as those with annual incomes verified at or below 200% of the federal poverty level. Typical weatherization services provided through the program include insulation, air-sealing, heating system repairs, and broken glass replacements.

Other State Programs

In addition to DNREC, Energize Delaware, also known as the Delaware Sustainable Energy Utility, offers several programs to help residents and businesses save money through clean energy and energy efficiency. Information about these programs is available at

What if my question was not answered?

If your question was not answered in the FAQ, please give us a call at 802-484-5645 or email us at