Scatter Wash Energy Storage rendering
Scatter Wash Energy Storage / PhoenixAZ
How do you build one of the largest energy storage projects in Arizona?

Mortenson was selected as the EPC for this 255 megawatt / 1,020 megawatt-hour battery storage project in Phoenix Arizona. Once complete, the project will be one of the largest in the state of Arizona. 

The 255 MW / 1,020 MWh facility is expected to become operational in April 2025. The project’s batteries can store enough electricity to power more than 250,000 homes for 4 hours daily for 20 years. 

Scatter Wash will provide APS customers with reliable energy, support increased power demand, and store significant amounts of renewable energy from solar power plants on its grid to use when it is needed, particularly in the summertime when extreme heat and electricity demand is high in Arizona. 

Strata entered into a 20-year tolling agreement with APS for its Scatter Wash battery storage complex last year. This award resulted from the All-Source RFP APS conducted, which was initiated to meet the growing needs of residential and business customers with affordable, reliable, and clean electricity. Under the terms of the agreement, Strata will build, own, and operate the Scatter Wash battery storage complex as part of the firm’s growing portfolio of clean-energy assets. 

Tesla’s Megapack 2XL, a fully integrated battery system featuring advanced battery technology, software, and power conversion systems, will be used throughout the project. These battery systems will efficiently store and dispatch electrical energy to and from the grid during optimal periods. 

Strata's development of Scatter Wash is supported by the Investment Tax Credit (ITC) for standalone energy storage created by the Inflation Reduction Act (IRA) of 2022. Mortenson facilitated IRA compliance for Strata on the project. 

Facts And Figures

Completion: 2025

255MW / 1020MWh energy storage 

Delivery Methods


The Team