Marigold Energy Center
About the project
SRP is planning the Marigold Energy Center, a mixed generation and storage facility project designed to meet near-term energy and capacity needs in central Arizona.
Plans are anticipated to include:
A 230-kilovolt (kV)/500 kV substation | |
Approximately 4 miles of new 230 kV transmission lines | |
600 megawatts (MW) of solar generation | |
400 MW of battery energy storage | |
Up to 675 MW of gas-fired generation |
This project will build on SRP’s commitment to provide Arizona with reliable and affordable power to keep up with economic growth. The project has the potential for collaboration with Electrical District No. 3 (ED3), a regional public power utility serving the communities of Maricopa, Stanfield and the surrounding area. ED3 is evaluating a potential partnership with SRP to procure a portion of the energy generated by the Marigold Energy Center, enhancing its ability to serve local customers with reliable and competitively priced electricity.
Why is this project needed?
When completed, these generation and transmission resources will strengthen the power grid and help ensure that SRP can meet the electricity demand of a rapidly growing population. This combination of technologies will provide flexible, dispatchable capacity to support the growing customer base in Maricopa and Pinal counties while enhancing grid reliability and enabling the integration of intermittent renewable energy resources.
Power Plant and Transmission Line Siting Committee Hearing
After completing an evidentiary hearing which took place from Sept. 21-25, 2026, the Arizona Power Plant and Transmission Line Siting Committee voted to recommend the two Certificates of Environmental Compatibility (CEC) for the Marigold Energy Center.
The next step is for the applications to be brought before the Arizona Corporation Commission in an open meeting anticipated to take place in the next few months. Details will be posted here:
Hearings and Meetings | Arizona Corporation Commission (Opens in a new tab)
CEC Application
On Aug.14, 2026, and Aug.18, 2026, SRP filed CEC applications for the transmission line and thermal plant components of the Marigold Energy Center.
Additional documents filed with the ACC relating to SRP’s application
Class I Air Permit Application
On September 11, 2026, SRP submitted an application for an air permit with the Pinal County Air Quality District for the Marigold Energy Center thermal plant.
Proposed location
Current proposed Marigold Energy Center location.
Past events
July 28, 2026: Open House Meeting
SRP hosted an open house at the Stanfield Elementary School on July 28, 2026.
Mar. 25, 2026: Open House Meeting
SRP hosted an open house at the Stanfield Elementary School on March 25, 2026.
Dec. 10, 2025: Open House Meeting
SRP hosted an open house at the Stanfield Elementary School on December 10, 2025.
Contact us
If you have questions about the project, please complete the form below, call (602)236-2872(602) 236-2872 or email [email protected].
