Salt River Project joins big boys of battery storage

It is human nature to crave power, be it Alexander the Great’s conquests of the Mediterranean and beyond, or the rigorous training sessions weightlifters put themselves through. If you’re the Salt River Project (SRP), you crave not only electrical power, but its retention, too.
In this quest for power, the utility cooperative has made plans to construct a project the likes of which Arizona has never seen. The Sonoran Energy Center will be a 250 MW, 1,000 MWh battery project, located in Little Rainbow Valley, south of the Phoenix suburb of Buckeye. Sonoran will be the largest battery system in the state of Arizona and among the largest in the country.
SRP also announced the Storey Energy Center, a solar and energy storage system in Coolidge, Arizona, with 88 MW of solar and energy storage capacity. Oddly, SRP did not expand on that capacity, but it is likely that the 88 MW are the solar generation capacity, with the storage system being a four-hour battery – meaning it would be 352 MWh.
The project is impressive in its own right, but being announced on the same day as Sonoran makes it feel like the equivalent of scoring a game-winning touchdown on the same day that your brother lands on the moon. Both the Sonoran and Storey Energy Centers are set to come online by June 2023 and will be owned and operated by subsidiaries of NextEra Energy Resources.
Let’s get some perspective on the size of the Sonoran project. The world’s largest announced lithium-ion batteries are the 316 MW / 2528 MWh Ravenwood project in New York City, the 409 MW / 900 MWh FPL facility in Florida, the 300 MW / 1200 MWh system by Vistra Energy, and a 182.5 MW / 730 MWh system by Tesla at the Moss Landing facility in California, and the recently announced 300 MW / 1.2 GWh Eland project by 8minute Solar Energy in Los Angeles. So while Sonoran is not the largest, it will become a proud and prominent member of the Big Boy Battery Club (trademark pending).
While having a bit more than 200 MW of solar capacity to its utility name thus far, SRP is on the hunt to change that number – and fast. The co-op is looking to add 1,000 MW of new utility-scale solar energy to its portfolio by the end of 2025. So far, we know of a 100 MW plant in Eloy by sPower, a 100 MW plant, also in Coolidge by NextEra Energy Resources, a 250 MW project with storage near Buckeye, which will likely feed Sonoran, the aforementioned 88 MW Storey Energy Center and another 100 MW plant that is so juvenile it is shrouded in mystery.
All these projects will add considerable capacity to the state with the third most capacity in the country at 3,873 MW. With Florida and Texas adding more and more capacity by the day, it looks like SRP is doing all that it can to maintain Arizona’s considerable utility-scale solar status. Residential solar in Arizona is a story for another time.