Salt River Project said Tuesday that it plans to seek approval from its board in September to develop the mixed-resource Marigold Energy Center, about 45 miles south of Phoenix, in order to serve growing demand in Maricopa and Pinal counties, Arizona.
The project includes 400 MW of battery storage, 600 MW of solar generation, up to 675 MW of gas generation, a new substation and four miles of 230-kV transmission lines, the public power utility said.
The Marigold project was announced last year, along with informational sessions for the local community of Stanfield, Arizona. On Tuesday, SRP said it would host an additional in-person open house and virtual meeting “to share information, seek public input and answer questions” about the project.
SRP plans to hold an informational session July 28 in Stanfield and a virtual open house on July 29. Previous sessions were held at the Stanfield Elementary School in December and March.
The project “will build on SRP’s commitment to provide Arizona with reliable and affordable power to keep up with economic growth,” according to the utility’s web site. The project has the potential for collaboration with Electrical District No. 3, a regional public power utility.
“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,” SRP said.
SRP is expanding the storage resources on its system to meet rising demand reliability, affordably and with cleaner energy, the utility says.
In June, the utility announced an agreement with Google-backed Energy Dome to add a 19-MW, 10-hour carbon dioxide-based battery system to the grid, co-located at SRP’s Coronado Generating Station in St. Johns, Arizona. The project was selected through a request for proposals that SRP issued in 2024.
And in October, SRP tapped ESS Tech to develop a 5-MW/50-MWh iron flow battery through a pilot project and storage purchase agreement.
