Maintains Reliable Energy at the Lowest Cost, Reduces Carbon Emissions by 40 Percent

At a Glance:

• Tucson Electric Power plans to convert Units 1 and 2 at the coal-fired Springerville Generating Station to operate on natural gas by 2030 to maintain reliable, affordable service and support local employment.
• The project will help TEP maintain reliable, affordable service for existing customers by replacing nearly 800 megawatts (MW) of retiring coal-fired capacity. The need for replacement capacity was communicated in TEP’s 2023 Integrated Resource Plan.
• The fuel conversion will reduce the units’ carbon emissions by 40 percent, helping TEP make progress toward our goal of net zero direct greenhouse gas emissions by 2050. TEP already has reduced carbon emissions from power generation by more than 38 percent since 2019.

TUCSON, Ariz.--(BUSINESS WIRE)--Jul. 29, 2025-- Tucson Electric Power (TEP) plans to convert two units at the coal-fired Springerville Generating Station (SGS) to run on natural gas by 2030. The project will maintain access to affordable, around-the-clock energy while reducing carbon emissions and preserving local jobs.

“Our SGS conversion project will extend the life of a plant that has powered Tucson’s growth for more than four decades,” said Susan Gray, TEP’s President and CEO. “It will help us provide reliable, affordable, and increasingly sustainable service while extending our productive partnership with communities in the White Mountains region.”

Arizona Governor Katie Hobbs praised the project. “A resilient grid that’s reliable, affordable, and sustainable is core to delivering on the Arizona Promise,” Hobbs said. “This plan will deliver cleaner air and lower costs, while strengthening communities in northeastern Arizona and building a more resilient energy future.”

Cost-Effective Capacity

The conversion will provide comparable capacity to the coal-fired units while costing less than building new resources such as a new combined cycle natural gas-fired facility or solar plus long-term energy storage systems that provide comparable reliability.

The natural gas conversion also will provide greater cost certainty compared to the continued use of coal. TEP’s 2023 Integrated Resource Plan called for the retirement of SGS Units 1 and 2 in 2027 and 2032, respectively, due to rising fuel costs, increasing delivery risks, anticipated mine closures, and environmental considerations and regulation. Although current federal policy is supportive of coal-fired generation, those long-term risks remain.

Natural gas-fired generators provide advantages over coal-fired power plants on today’s energy grid, as they can better accommodate and support increasing levels of intermittent wind and solar power. Coal plants are designed to operate at steady levels and cannot easily ramp up or down in response to customer needs and renewable energy output.

Lower Carbon Emissions

The conversion will reduce the units’ carbon dioxide emissions by 40 percent, supporting TEP’s goal of achieving net zero direct greenhouse gas emissions by 2050 without compromising on reliability or affordability. We are pursuing that aspirational goal through a balanced energy mix that also supports greater resiliency and energy security.

Natural gas generation can serve as a “bridge” to a cleaner energy future, providing ready, reliable power while newer technologies mature. Options may include cost-effective long-duration storage, small modular nuclear reactors, and a switch to hydrogen as a carbon-free fuel source for plants previously powered by natural gas.

“Achieving our 2050 net zero goal will require an all-of-the-above approach, including investments in clean energy solutions and partnerships with customers to encourage thoughtful energy use,” Gray said. “While we cannot predict exactly how we’ll achieve net zero carbon emissions, we know that efficient, reliable natural gas generation will be a part of our path toward that goal.”

Supporting Local Economies

The SGS repowering project will support the continued availability of affordable, reliable power in Southern Arizona for local residents and businesses. It will also maintain jobs and tax revenues for Springerville, Eager, St. John’s and other White Mountains communities that our SGS employees call home.

“This transition at Springerville is a step toward a more sustainable energy future that doesn’t leave rural Arizona behind,” said U.S. Sen. Ruben Gallego (D-Ariz.). “By moving away from coal while maintaining affordable and reliable power, TEP is showing that we can protect jobs, while propelling innovative energy solutions at the same time. Arizona needs smart, balanced solutions like this that support working families, strengthen local economies, and keep us moving toward our clean energy goals.”

TEP has been operating SGS since 1985 on a high desert plain about 175 miles northeast of Tucson, near the Arizona-New Mexico border and about 15 miles outside of Springerville, Ariz. It was one of several coal-fired power plants developed during the 1970s and 1980s in the Four Corners area to support growing communities in the southwest United States.

“Springerville Generating Station isn’t just a power plant. It’s a lifeline to the Round Valley communities,” said Springerville Mayor Shelly Reidhead. “This commitment to repower the plant with natural gas helps ensure a brighter future for this region, saving jobs, stabilizing the tax base and attracting future energy investments.”

SGS Unit 1 came online in 1985, while Unit 2 came online in 1990. TEP owns Units 1 and 2 and operates all four units at the plant, including Unit 3, a 400 MW unit owned by Tri-State Generation and Transmission Association, and Unit 4, a 400 MW unit owned by Salt River Project (SRP).

Please visit our Media Resource Page for a video interview about TEP's plan to repower SGS and b-roll footage of the plant.

TEP provides safe, reliable electric service to more than 450,000 customers in Southern Arizona. For more information, visit tep.com . TEP and its parent company, UNS Energy, are subsidiaries of Fortis Inc., a leader in the North American regulated electric and gas utility industry. For more information, visit fortisinc.com .

View source version on businesswire.com: https://www.businesswire.com/news/home/20250729220047/en/

News Media Contact:
Joseph Barrios
(520) 884-3725
jbarrios@tep.com

Source: Tucson Electric Power