CPS Energy Closes Bidding for 20 MW San Antonio Battery Storage and Microgrid RFP

The CPS Energy San Antonio battery storage microgrid RFP reached its proposal deadline August 7, moving the city-owned Texas utility into evaluation of bids for up to 20 MW of distribution-scale battery energy storage and a microgrid intended to strengthen resilience for customers and critical infrastructure. CPS Energy plans to own and operate the resulting assets, making the procurement a direct utility investment in distributed storage and islandable power infrastructure rather than a solicitation for energy from independently owned projects.

The utility plans two battery storage sites in the eastern and southern portions of San Antonio, with one of the battery systems supporting a microgrid capable of disconnecting from the larger electric system during prolonged outages and other grid disturbances. CPS Energy is targeting commercial operation by the second quarter of 2028 and says it plans to make selections later in 2026 after evaluating the proposals.

The procurement combines distribution batteries with an islandable microgrid

According to the CPS Energy procurement announcement, the utility is seeking up to 20 MW of distribution-scale battery energy storage systems and a microgrid powered by one of those systems.

The distinction between the battery projects and the microgrid is important. Battery storage can provide energy and power services on the distribution system, while a microgrid adds controls and electrical architecture that allow a defined group of loads and generation resources to operate independently when conditions require it.

CPS Energy says the proposed microgrid will be able to remain connected to the larger utility system during normal operations or disconnect and operate in island mode during prolonged outages, extreme weather and other grid disturbances.

That capability can allow designated facilities or infrastructure within the microgrid boundary to maintain electricity service even when the surrounding distribution system is unavailable.

CPS Energy plans to own and operate both storage sites

The CPS Energy San Antonio battery storage microgrid RFP is structured around utility ownership rather than a power purchase agreement with a third-party asset owner.

CPS Energy says it plans to own and operate both battery storage sites. The installations are expected to be located in the eastern and southern portions of San Antonio, although the utility has not publicly identified the precise project sites in its announcement.

The utility is targeting the second quarter of 2028 for the projects to become operational.

That schedule leaves time for proposal evaluation, contracting, engineering, permitting, equipment procurement, construction, interconnection work and commissioning after the competitive process is completed.

The projects are tied to a federally supported resilience program

The battery systems and microgrid are part of CPS Energy’s Community Energy Resiliency program, which the utility says is supported by the U.S. Department of Energy.

The program focuses on grid innovation as San Antonio’s electricity needs continue to grow. Distribution-scale storage can provide utilities with a flexible resource closer to customer loads than conventional centralized generation, while microgrids can add another layer of resilience for selected facilities.

The U.S. Department of Energy’s resilience resources describe grid resilience in terms of the ability to prepare for and recover from disruptive events, a role increasingly associated with combinations of distributed generation, storage and advanced controls.

For CPS Energy, the planned installations also create an opportunity to gain operating experience with utility-owned batteries on its distribution network and with an islandable microgrid serving local infrastructure.

The proposal window has closed, but no winner has been announced

CPS Energy’s current procurement schedule identifies August 7 as the deadline for proposal submissions and the point when the portal closes and evaluation begins.

The utility says it intends to make selections later this year. It has not disclosed the number of bids received, bidder identities, proposed battery technologies, project costs or the exact amount of storage capacity represented by the submissions.

The 20 MW figure is therefore a solicitation ceiling, not an announced award.

CPS Energy also has not disclosed the megawatt-hour capacity or discharge duration required for the batteries in its public announcement. Without that information, the systems should not be characterized as two-hour, four-hour or any other specific duration.

San Antonio is adding resilience as electricity demand grows

CPS Energy serves more than 996,000 electric customers and describes itself as the nation’s largest public power, natural gas and electric utility.

Adding storage at the distribution level can provide operational flexibility without relying exclusively on new centralized generation. Depending on final system design and operating strategy, batteries can support peak management, grid operations and resilience while responding more rapidly than many conventional generating resources.

The microgrid component gives the procurement additional significance because it tests how storage can be combined with controls and distribution infrastructure to maintain service during disruptions.

Once evaluations are completed, the selected projects should provide more detail about how CPS Energy intends to use the batteries during normal grid operations and which critical loads the microgrid will be designed to protect during islanded operation.

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The Microgrid Media Editorial Desk reports on microgrids, energy storage, grid modernization, data center power demand, distributed energy resources, and energy policy. Reporting published under the Editorial Desk byline is developed from primary regulatory records, utility filings, government documents, company disclosures, and independently verifiable sources, and is reviewed under Microgrid Media’s editorial standards.

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