CPS Energy, the largest municipally owned electric and natural gas utility in the United States, and OCI Energy, a leading developer, owner, and operator of utility-scale solar and battery energy storage projects, have entered into a long-term storage capacity agreement (SCA) for a 120 megawatt (MW) – 480 megawatt-hour (MWh) - battery energy storage project called "Alamo City ESS LLC" which will be located in southeastern Bexar County, Texas.

Under the SCA, OCI Energy will develop, finance, construct, own, and operate the Project. CPS Energy will have operational control of the Project to serve electrical demand in the San Antonio region.

Additionally, as part of a related community benefits agreement, OCI Energy will contribute $250,000 to the University of Texas at San Antonio (UTSA). OCI Energy will work with UTSA to establish educational initiatives tied to the $250,000 contribution.

This four-hour duration battery storage project will be newly constructed and is expected to be online in late 2026, serving the energy needs of the San Antonio community for a 20-year period. Four-hour duration means the amount of time the battery storage project can discharge at its full power capacity (120 MW) before entirely depleting its stored energy.

The addition of this 120 MW project is a continuation of the utility's execution of its Vision 2027 generation plan and brings CPS Energy's battery storage under contract to 520 MW.

"Our community is growing at an exponential rate, and we have been focused on our Vision 2027 strategy to meet this growth," said Rudy D. Garza, President & CEO of CPS Energy. "I'm proud of our team for delivering on our commitment to increase energy capacity for our growing community. Every megawatt that we can provide our customers counts."

"As a San Antonio-based company, we are thrilled to build on our successful, and more than a decade-long collaboration with CPS Energy, said Sabah Bayatli, President of OCI Energy. "Together, we've delivered multiple utility-scale solar projects to Texas's power grid, paving the way for renewable energy in San Antonio and across Texas. Now, we're embarking on an exciting new chapter—introducing large-scale battery energy storage to San Antonio to help secure reliable and sustainable power for our community today and for generations to come."

"This agreement is another important step toward a future focused on reliability, sustainability, and clean energy," said Mayor Ron Nirenberg. "This battery storage project continues the productive relationship between CPS Energy and OCI Energy that has helped our community become a national leader in the renewable solar power industry and preparing for the energy landscape of the future."  

In January 2023, the CPS Energy Board of Trustees approved a generation plan as part of the utility's Vision 2027 strategy to power the community into the future. CPS Energy has since added 1,710 MW of owned natural gas generation, 500 MW of natural gas firming capacity, an additional 84 MW of wind capacity, and contracted 730 MW of solar energy.

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