WAPA » Transmission » Environmental review-NEPA

Arizona Peaking Capacity Energy Storage Project, DOE/EA-2123

About the project

Western Area Power Administration (WAPA) is preparing an environmental assessment (EA)* to evaluate the environmental effects of the Arizona Peaking Capacity Energy Storage Project (Project) in which the AES Energy Storage, LLC, has submitted a project proposal to WAPA for potential financing under the Transmission Infrastructure Program for the proposed Project.  WAPA could provide project financing from the United States Treasury under authority granted to WAPA under Section 402 of the American Recovery and Reinvestment Act of 2009 (Recovery Act) (Public Law 111-5), which amended the Hoover Power Plant Act of 1984 (Public Law 98-381). The proposed Project would involve the construction of a 100-megawatt (MW) battery energy storage facility adjacent to the existing Arizona Public Service Company's (APS) Westwing Substation within Maricopa County, Arizona.

*DISCLAIMER:  WAPA's preparation of the EA or performance of any other environmental analysis related to this Project is not a final decision or determination as to whether WAPA will provide project financing for this Project

project features

The proposed Project would construct a 100-MW battery storage facility in Maricopa County, Arizona. The proposed battery storage facility would utilize advanced technology batteries and control systems contained within an approximately 523-foot by 295-foot (154,300 sf or 3.5-acre) fenced area. The proposed battery storage facility would consist of battery storage containers, inverters/transformers, communications equipment, switchgear, and heating, ventilation, and air conditioning (HVAC) units. In addition, transmission poles and associated electricity transmission facilities would connect the project site to the APS Westwing Substation to the south.

current status
WAPA concluded the project scoping process which ended on October 25, 2019.  Project scoping is a process used to inform the public of a proposed activity, which in this case involves WAPA evaluating AES Energy Storage, LLC's request for project financing.  WAPA received a lot of good comments and insight to help guide us on our environmental review process.  The next step in our environmental review is the preparation of an Draft Environmental Assessment (EA) document which will outline the specifics of the project and it's potential to impact resources located in and near the project area.  ​When the ​Draft EA is available, interested parties will be receiving another letter from WAPA with instructions on how you can review and comment on the Draft EA and participate in public meetings that will occur near the project vicinity when the Draft EA is out. 


We would like to know of any issues, concerns, and suggestions you may have regarding the proposed Project. Your comments will help define issues and alternatives for consideration in the environmental review processes mentioned above. Comments can be provided in writing or by phone to the contact listed below.

Mail: Western Area Power Administration, HQ
ATTN: Andrew M. Montaño, NEPA Document Manager
P.O. Box 281213
Lakewood, CO 80228-8213
Phone: (720) 962-7253

Page Last Updated: 8/19/2020 10:09 AM