News and Updates

The Information You Need

If you are a member of the media, please email ngarcia@azcc.gov or call (602) 542-0728.

Commissioner Walden Votes to Strengthen Commission Oversight of Arizona’s Transmission Grid

Oct 16, 2025, 09:52 by Nicole Garcia

Phoenix, Ariz. - During the October 15, 2025 Open Meeting, Commissioner Rachel Walden voted to hold utilities accountable to provide the Arizona Corporation Commission with the information necessary to ensure our state’s electric transmission grid is reliable. Arizona Revised Statute requires any developer or utility to provide information about their ten-year transmission plan to the Commission. However, ensuring our grid is reliable and ready to meet our future energy needs requires that our utilities provide more information than has been required of them to submit from previous Commissioners spanning 26 years. 

 “Finding the least cost, most reliable model includes transmission, not just electricity generation. None of the answers from our state utilities today inspired any confidence in me that these issues are a priority," said Commissioner Walden.  "I am not convinced that additional build out of renewables, while also having to add firm capacity as well as back up generation, is saving Arizonans money. I know that Arizonans are concerned with these issues, especially as we head into accelerated growth in our state. The Commissioners, as elected by the public, are faced with these questions and comments almost daily, and our actions are held accountable to the public."

Arizona utilities biennially file a Ten-Year Forecast for their transmission systems. The Thirteenth Biennial Assessment indicates a projected growth rate of approximately 3% per year each year for the next ten years between 2024 to 2033. This is slightly higher than has been forecasted in prior years’ assessments. The Commission noted that as Arizona continues to deploy more renewables, the utilities must increasingly work together with neighboring utilities in other states to address new operational challenges that arise due to the addition of intermittent resources being added to our State’s grid.

“Arizonan’s will not bear the costs and impacts of supporting neighboring states’ Green New Deal policies”, Commissioner Walden stated emphatically.

“Ensuring our utilities have sufficient generation capacity to serve our customers during peak demand along with a reliable transmission grid to handle that capacity is paramount,” said Commissioner Walden. “The Commission must ensure that any transmission or generation solutions to mitigate grid concerns, such as line congestion created by the interconnections from new generation sources, or offtakes from the grid by large customers such as data centers and hyperscalers, are borne by the creators of those grid concerns, not Arizona ratepayers.”

Commissioner Walden introduced an amendment, which passed by a 5-0 vote, requiring utilities to submit business confidential reports to the Commission regarding line congestion on their systems, along with projections of load growth pockets on their systems to better enable the Commission to assess grid reliability and impacts of interconnection requests on the transmission grid as a whole. 

Commissioner Walden supported and thanked Commissioner Lea Márquez-Peterson for her amendment, which would require that utilities submit reports on all grid enhancing efforts, such as line reconductoring, grid hardening, etc. that they perform on their systems.

"I will be watching the Biennial Transmission Assessments and Integrated Resource Plans closely, and investigating these issues in all future rate cases," concluded Commissioner Walden.