Officials from SRP, Plus Power LLC, and the City of Avondale met on Wednesday for a ceremonial groundbreaking to kick off construction mobilization at the new large-scale battery facility, Sierra Estrella Energy Storage on West Broadway Road in Tolleson.

The facility will store up to 250 megawatts (MW), or 1,000 megawatt hours (MWh), and will be the largest standalone battery facility built in Arizona once online in 2024. Storage from the project will serve SRP customers during times of peak electricity demand and facilitate the continued integration of renewable resources into the SRP power system.

“This facility will have enough stored energy to power more than 56,000 average size homes for a four-hour period,” said Grant Smedley, Director of Resource Planning at SRP. “Battery storage can help provide energy to the grid when other resources may not be available and is part of SRP’s overarching strategy to meet rising energy demand while reducing carbon emissions.”

The Sierra Estrella facility is one of two battery storage projects SRP announced in fall of 2022 with Plus Power, with both projects scheduled to come online by summer of 2024. The other, a 90 MW, or 360 megawatt-hour, project called Superstition Energy Storage, will soon be built in Gilbert, AZ. These projects along with additional battery contracts that SRP has entered, will help SRP surpass 1,100 MW of battery storage by 2024, which is among the largest utility-scale battery investments in the Western U.S.

Sierra Estrella Energy Storage is expected to generate 30 to 40 high-paying construction jobs throughout its development, utilize lithium-ion technology manufactured by Tesla in the U.S., and expand the Avondale district property tax base. Plus Power will design, build, and operate the facility to updated national safety codes and standards for Battery Energy Storage Systems.

“We are thrilled to partner with SRP on the Sierra Estrella battery storage project, and to contribute to local grid reliability with job and tax benefits for Avondale and the nearby communities,” said Molly Emerson, Director of Project Development at Plus Power. “Plus Power’s projects represent a bold step forward for the Southwest energy market, and will act as a cornerstone of our growing portfolio of operating projects.”

Plus Power is coordinating with the Avondale Fire Department to prepare a thorough Emergency Response Plan for the facility. In the coming months the two organizations will conduct onsite training to ensure local first responders are engaged in safety planning throughout project construction and operation.

“Avondale is proud to partner with SRP and Plus Power to welcome the Sierra Estrella Energy Storage facility which will be a valuable asset to our community for decades to come,” said Avondale Councilmember Veronica Malone. “The project will provide necessary power to the region with no onsite air polluting emissions, will incorporate the latest safety standards, and has been designed with thorough planning and preparation.”

SRP will continue to develop and deploy evolving storage technologies safely and cost-effectively as part of the SRP’s commitment to reducing carbon intensity (from 2005 levels) by more than 65 percent by 2035 and 90 percent by 2050.  SRP has also closed the largest coal plant in the Western U.S. and will have retired approximately 2,600 MW of coal-fired generation by 2032. With these strategic resource additions and decisions, nearly half of all retail energy delivered to SRP customers will come from carbon-free resources by 2025.