Salt River Project inks deal with Invenergy for 200-megawatt solar plant in Pinal County
Arizona nonprofit utility company Salt River Project says it has entered an agreement with power infrastructure development company Invenergy LLC to build a new solar and battery storage project.
Called SunDog Energy Center and located in Pinal County south of Phoenix, the project will add 200 megawatts of energy to SRP’s grid, along with 200 megawatts of four-hour battery storage.
SRP said the project will provide enough capacity to power as many as 45,000 homes in the Valley, where the utility serves more than a million customers. SRP said it is another step in its efforts to more than double its power system’s capacity in the next decade as demand continues to increase amid explosive residential and industrial — especially data center — growth.
“Adding solar and storage resources is part of SRP’s all-of-the-above strategy to meet our customers’ growing energy needs with reliable, affordable and sustainable power,” said Bobby Olsen, SRP associate general manager and chief power system executive, in a statement. “We look forward to working with Invenergy to bring the benefits of the SunDog Energy Center to our customers and the community.”
The added storage capacity follows momentum in recent years that has made Arizona the state with the third-highest amount of utility-scale energy storage as of 2025, with the fastest rate of growth.
While this project isn’t Chicago-based Invenergy’s first in Arizona, it is its first partnership with SRP.
“From the start, SRP has been clear about what it needs to serve its customers, and we’re able to bring the right energy mix as they plan for growth,” said Ted Romaine, Invenergy’s executive vice president for origination, in a statement. “As energy demand continues to grow in Arizona and across the country, hybrid projects like SunDog help strengthen the grid and give utility customers reliable, affordable energy solutions they can trust.”
Invenergy also has several projects alongside APS
Invenergy’s other Arizona projects include partnerships with Arizona Public Service, including on the 70-megawatt Yuma Solar Energy Center, which reached commercial operations about a year ago. Other APS collaborations include the El Sol Energy Storage Center in Youngstown and the Hashknife Solar Energy Center in Navajo County, amounting to 250 megawatts of energy capacity as of last year.
The Yuma facility was Invenergy’s first solar production facility to reach commercial operations in Arizona, but it was its 11th energy storage center in the state at the time. The new SRP facility brings Invenergy’s project count in Arizona to 17.
In total, Invenergy’s operational and under-construction portfolio in the Grand Canyon State accounts for 545 megawatts of solar power and 736 megawatts of energy storage.
The SunDog plant will be Invenergy’s first operational site in Pinal County, where the company expects to make a $209 million impact in local tax revenue, land costs and lease payments connected with the project. In addition construction is expected to support between 200 and 400 jobs.
SRP recently proposed giving its customers a temporary 3% price cut for the upcoming summer months, and the utility’s board of directors is scheduled to vote on that proposal March 26. That proposal comes a few months after SRP put into effect an overall 2.4% price increase in November to raise base revenue by $169 million to pay for upgrades to the electric system and cover other costs.
SRP’s latest actions comes as the it prepares for a hotly contested battlefor seats on its energy and water boards. The board election is April 7.