Project Overview

Sierra Estrella Energy Storage is a 250 MW / 1,000 MWh state-of-the-art battery energy storage system that provides clean, firm capacity to Arizona utility Salt River Project. The facility is located on approximately 11 acres of land on a disused portion of an operating dairy plant.

Sierra Estrella interconnects to the utility at the existing Rudd substation directly adjacent to the project site. The project received approval on a Conditional Use Permit from the City of Avondale, Arizona in December 2021.

Sierra Estrella commenced commercial operations in June 2024 and is supporting the integration of higher amounts of low-cost, readily available renewable energy. The facility operates as a zero-emissions, carbon-free system that provides power and stability to the Arizona and Western electric grids.

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