Arizona utility APS signs 20-year tolling agreement with Strata for 1GWh BESS

LinkedIn
Twitter
Reddit
Facebook
Email

Developer Strata Clean Energy and utility Arizona Public Service (APS) have agreed a 20-year tolling agreement for a 255MW/1GWh battery energy storage system (BESS).

The pair announced the agreement, which will see Strata build, own and operate the project but exclusively provide its energy to APS over the period, yesterday (24 May).

The project, called Scatter Wash, is located in Phoenix and will increase clean energy capacity in one of the US’ fastest growing cities and stabilise the grid in a drought-prone region. A spokesperson said it has an investment value of US$500 million.

It resulted from an All-Source request for proposals (RFP) that APS conducted in May last year which saw it commit to adding 1GW of clean energy resources. The utility is the largest in Arizona, serving 1.3 million homes and businesses.

This article requires Premium SubscriptionBasic (FREE) Subscription

Enjoy 12 months of exclusive analysis

Not ready to commit yet?
  • Regular insight and analysis of the industry’s biggest developments
  • In-depth interviews with the industry’s leading figures
  • Annual digital subscription to the PV Tech Power journal
  • Discounts on Solar Media’s portfolio of events, in-person and virtual

Or continue reading this article for free

The four-hour duration is similar to the market standard in California, which is required by grid operator CAISO’s Resource Adequacy framework and means BESS projects primarily monetised through energy and capacity, rather than ancillary services.

Scatter Wash first announced it was working on the project in late 2021, when it said it would be connected to the grid in 2024. Yesterday’s announcement did not give a firm commercial operation date, however. A related substation for the project may not be coming online until the end of 2023 according to this regulatory document.

Josh Rogol, president of Strata Clean Energy, commented: “We believe that APS will continue to be a leader in battery energy storage and that our experienced Scottsdale-based team is well positioned to help move the state towards achieving its clean-energy objectives with projects like Scatter Wash. We have a large pipeline of additional clean energy projects in the Western United States and world-class execution capabilities.”

The project is the same in energy capacity as a 250MW/1GWh BESS being developed by Plus Power for another big Arizona Utility, Salt River Project (SRP), set to come online in 2024. Tucson Electric Power (TEP) is the other large utility in the state.

Grid-scale BESS projects in the Arizona have been on the larger side.  Recent ones covered by Energy-Storage.news include an 860MWh project system integrator Powin is deploying and a co-located 600MWh project being developed by developer BrightNight.

Read Next

August 21, 2025
CATL has partnered with renewable energy developer ACEnergy to supply 3GWh of battery energy storage systems (BESS) in Australia.
August 20, 2025
US-based renewable energy developer National Renewable Solutions (NRS) announced its 140MWac solar energy and 50MW battery storage Shallow Basket Energy project is now operational.
August 20, 2025
US Environmental Protection Agency (EPA) Administrator Lee Zeldin recently held a press conference in Hauppauge, New York, to address the concerns of battery energy storage system (BESS) installations with Long Islanders.
August 19, 2025
Major US utility company Duke Energy has submitted its final license application to the Federal Energy Regulatory Commission (FERC) to extend operation at the Bad Creek Pumped Storage Hydroelectric Station for an additional 50 years.
August 19, 2025
The Minnesota Public Utilities Commission (PUC) has approved a site permit for Spearmint Energy’s 150MW/600MWh battery energy storage system (BESS) in Kalmar Township.

Most Popular

Email Newsletter