Green Grant – Solar Hot Water and Geothermal

The non-residential and non-profit solar hot water and geothermal program is jointly run by DNREC and the SEU. This incentive program offers grants to qualified installations of solar hot water and geothermal systems in Delaware based on system sizes.

This program is open to all non-residential and non-profit solar hot water and/or geothermal customers in Delaware regardless of utility.

Program Highlight:
The maximum grant is appropriately sized for large systems. For both solar hot water and geothermal systems, the grants are capped at $200,000 per project.

Application Procedure:
The application should be submitted online and approved by the program before the construction process. If a grant for a non-residential or non-profit system is approved, it will be paid directly to the grantee after the completion of the construction.

To begin an application for the program, please click here. This will prompt you to set up an account at After you have set up an account, you can log in here and begin your grant application. Applications can be saved and edited before final submission.

To learn more about the online application steps, click here for an application example.

Details of the Grant:
The grants are based on the size of systems:

Solar Hot Water Non-Residential Non-Profit
($/OG300 or PE* Calculated kWh Saved) ($/OG300 or PE* Calculated kWh Saved)
SWH Water Heater Only $1.00 $1.50
SWH with Integrated Heating $1.00 $1.50
Maximum Grant $200,000.00 $200,000.00
Geothermal Heat Pumps Non-Residential Non-Profit
EER ≥18/COP≥3.6 Partial Load ($/ton) ($/ton)
First 2 Tons $800.00 $1,000.00
Over 2 Tons $700.00 $800.00
Maximum Grant $200,000.00 $200,000.00
*PE=Licensed Delaware Professional Engineer required if the system is not OG-300 compliant

Note: Grants for solar hot water systems cannot exceed 50% of the project cost. All solar hot water grants will be capped at 50% of the system cost. 

System Requirements:
• Eligible system size is limited to 80% of the thermal load.
• Solar hot water systems must either meet OG-300 certification by the Solar Rating and Certification Corporation (SRCC) or have energy savings calculated by licensed Delaware Professional Engineers.
• Geothermal systems must meet an Energy Efficiency Rating (EER) of at least 18 and a Coefficient of Performance (COP) of at least 3.6.

For further information about the program, please contact the Executive Director, Tony DePrima, at the DE Sustainable Energy Utility at 302-883-3048 or by email at

Learn more about solar hot water and geothermal systems:
US Department of Energy, Solar Water Heaters
US Department of Energy, Geothermal Heat Pumps