Coolidge Generating Station

The Coolidge Generating Station will be doubling in size over the next few years in order to accommodate increasing energy needs in the region. The increase in electric power will support an increase in Salt River Project’s renewables portfolio.

COOLIDGE — More people means more electricity. Due to increasing regional population, Salt River Project’s Coolidge Generating Station, located on the southern edge of the city, will more than double in size over the next five years.

The expansion of the project is being framed as necessary for SRP’s increased renewable commitments, despite the station's running on natural gas.

SRP representatives explained that the potential confusion is because in order to accommodate increased solar and other renewables on the grid, the utility will have to assure it can provide power at peaking times.

“When the sun goes down or it's not windy, those renewables cannot generate power directly,” said SRP spokeswoman Erica Sturwold. 

Sturwold added that while SRP is investing in battery storage and has two pilot projects it is currently monitoring, battery capacity is not yet enough to offset the need for other sources of electricity.

SRP’s stated goal is to add 2,025 megawatts of solar energy by 2025, and 350 megawatts of battery storage by 2023.

In addition to three new solar plants to help support Facebook’s data center in Mesa, SRP is actively working on a number of other new solar projects.

“There’s no doubt we are going to meet our expanded commitment,” Sturwold said on the company’s renewable projections. “It’s also definitely needed because of the sheer near-term energy demand we are seeing.”

The Coolidge expansion is being planned as a peaking resource; times of maximum energy need include very hot summer days, when air conditioners are running well into the evening hours. Due to climate change, the need to counteract extreme heat in the Valley will continue to intensify.

SRP is anticipating a 16% increase in peak energy demand by 2025, up to 1,200 megawatts.

Despite the close proximity to the scene of a natural gas line fire that killed two Coolidge residents, Sturwold confirmed that the broken pipeline was not connected to the generating station, on Randolph Road west of Sunshine Boulevard, and did not impact the site at all.

SRP paused operations the day of the accident to allow for an investigation, but got assurance from pipeline owner Kinder Morgan that it was a different pipeline, and the Coolidge station recently passed inspections in June.

The Coolidge gas plant was constructed by TransCanada in 2011 and was bought by SRP in 2019. Currently the site has 12 turbines. The expansion will add an additional 16 generating stacks, which are expected to be nearly identical to the current 85-foot-tall units at the site. Construction is expected to begin in 2023, with all of the new units going online by 2025.

City Economic Development Director Gilbert Lopez said that officials are excited for the potential benefits to Coolidge.

Although the power generated by the plant will go to cities and towns in Maricopa County, the construction will generate jobs and over $76 million in property taxes from 2024 to 2033.

“That’s a really good benefit to us,” Lopez said. “They’ve been a good, transparent neighbor.”

SRP is hoping to hold a virtual open house on the expansion by late September, and depending on the COVID situation and federal guidance, could hold in-person meetings later in the fall.

Those interested in learning more about the expansion project can check out


Aaron Dorman is the Casa Grande reporter at PinalCentral, covering government, schools, business and more. He can be reached at

(0) comments

Welcome to the discussion.

Keep it Clean. Please avoid obscene, vulgar, lewd, racist or sexually-oriented language.
Don't Threaten. Threats of harming another person will not be tolerated.
Be Truthful. Don't knowingly lie about anyone or anything.
Be Nice. No racism, sexism or any sort of -ism that is degrading to another person.
Be Proactive. Use the 'Report' link on each comment to let us know of abusive posts.
Share with Us. We'd love to hear eyewitness accounts, the history behind an article.