Salt River Project will pilot a 5 MW/50 MWh iron flow battery from ESS Tech, marking one of Arizona’s first large-scale LDS tests. (Utility Dive)
The project will use iron, salt, and water chemistry—materials ESS says are 90% US-sourced. The capacity will be sold to SRP under a 10-year storage agreement.
Why it matters: SRP plans to double its generation fleet over the next decade to meet surging demand in metro Phoenix. The utility already runs nearly 1,300 MW of storage, mostly lithium-based, and wants to see how iron flow performs in Arizona’s heat.