Tucson, Ariz. – UniSource Energy Services’ 2026 Integrated Resource Plan (IRP) describes a balanced approach for providing safe, reliable and affordable electric service over the next 15 years while advancing the company’s energy independence and supporting community growth.

The plan is designed to maintain reliable service and manage costs while continuing the transition to a more diverse resource portfolio that reduces reliance on regional energy markets.

After evaluating several potential scenarios, UniSource selected a balanced portfolio that will provide reliability at the lowest cost while delivering environmental benefits. The preferred portfolio would add 321 MW of new natural gas capacity, 190 MW of solar power, and 190 MW of battery storage by 2041. The IRP calls for increased energy reserves and includes resource adequacy analyses designed to ensure sufficient energy and capacity resources are available under a wide range of operating conditions.

“Our customers expect energy that is safe, reliable and affordable. This balanced, cost-effective plan puts us on a path toward meeting those expectations,” said Susan Gray, Chief Executive Officer. “By adding flexible natural gas resources, solar energy and battery storage, we can reduce our reliance on market power, strengthen reliability and prepare responsibly for future growth.”

Customer affordability remains a critical consideration in UniSource’s planning decisions. The preferred portfolio produced the lowest overall cost while maintaining reliability requirements. Projected customer costs under the preferred portfolio are about $40 million to $225 million lower than other portfolios analyzed. UniSource will continue using competitive all-source requests for proposals to identify cost-effective resources that can meet customers’ needs.

The plan includes solar resources that can provide low-cost energy during daylight hours and battery systems to shift that energy into higher-demand periods. It also includes flexible natural gas resources that can provide sustained output when renewable production is limited and stored energy has been depleted.

Some resources are already under development, including Dandelion Energy Park, a 140 MW solar power system paired with a 140 MW four-hour battery energy storage system in Maricopa County scheduled to begin operation in 2028. The preferred portfolio also includes the Black Mountain Expansion Project, which would add 196 MW of natural gas combustion-turbine capacity in 2030.

In addition to the preferred portfolio, UniSource evaluated high-load-growth scenarios to understand the resources and infrastructure needed to support economic development opportunities without shifting costs or creating reliability risks for current customers. The preferred portfolio provides a foundation capable of supporting future growth while preserving flexibility to respond as conditions evolve.

UniSource provides electric service to 106,000 customers in Mohave and Santa Cruz counties. It also provides natural gas service to 171,000 customers in northern and southern Arizona. For more information about UniSource, visit uesaz.com.

UniSource and its parent company, UNS Energy, are part of Fortis, Inc., a leader in the North American regulated electric and gas utility business. For more information visit fortisinc.com.

News Media Contact:
J.D. Wallace
520-801-6392
jd.wallace@uesaz.com