ACC Votes to Add Nearly 5,000 MW to the Arizona Electricity Grid; Continues to Prioritize Reliability, Affordability and Diversity

Phoenix, Ariz. - Since January 2025, at the start of the new year and after inaugurating three incumbent, and two new Commissioners, the Arizona Corporation Commission has voted and approved several items that will help Arizona electric utilities continue to meet the ever-increasing projected energy demand.

So far this year, the Commission has publicly heard, debated, and voted on several items during its monthly Open Meetings that support energy reliability and expand the state's energy infrastructure. From January through August 2025, the Commission has approved several applications, and energy-related projects, which will lead to the construction of about 42 miles of new transmission lines, and the increase of the state's electricity net generation and net summer capacity by about 4,750 MW. That includes 4,550 MW of new solar generation and battery storage facilities, as well 200 MW of natural gas expansion.

"Ushering in the next era of generation and transmission in Arizona is a ​challenge that is going to require cooperation from all levels of government," said Chair Kevin Thompson. "Thankfully, the Commission is already well down this path, addressing natural gas infrastructure, data center rate policies, and the future of new nuclear in the state."

"As Arizona continues to grow, we must ensure the power grid keeps pace to meet the growing energy demands of the future," said Vice Chairman Nick Myers. "Every megawatt and mile of transmission approved by the Commission represent more than growth and economic development - they represent a more reliable and resilient grid and a commitment to long-term energy security for families and businesses across the state."

"Comprehensive and diverse generation and transmission projects should continue to be explored and adopted," said Chair Thompson. The latest data from the U.S. Energy Information Administration's Electric Power Monthly report reveals the current diversity of Arizona's energy portfolio. The data indicates that 43% of the state's net generation in June 2025 came from natural gas, followed by nuclear at 26%, utility-scale solar at 17%, coal at 6%, hydroelectric at 5%, and wind at 3%. Compared to nationwide data, the U.S. net generation of utility scale solar was 8%. Arizona solar facilities produced more than twice that amount in the month of June.

"The Commission continues to prioritize grid reliability in its actions to ensure that all ratepayers and especially vulnerable Arizonans have electricity especially on the hottest summer days," said Commissioner Márquez Peterson. "Energy reliability is also key to the continued economic development success our state has experienced. Arizona is facing incredible energy load growth. We will continue to balance the needs of our ratepayers across the state with the investment in infrastructure needed to ensure our grid reliability."