B2U Brings Second-Life EV Battery Storage Online on Texas, US Grid

A battery storage facility built entirely from retired electric vehicle packs has crossed into commercial service, marking a step for second-life battery technology in one of the country's most active storage markets.

B2U Storage Solutions announced that its Bexar Martinez battery energy storage system (BESS), located in Texas, has begun commercial operations and is delivering 28 MWh of grid services to the Electric Reliability Council of Texas (ERCOT), the state's main grid operator.

Built From Retired EV Packs, Not New Cells

The defining characteristic of the Bexar Martinez project is its battery supply. According to B2U's announcement, the facility runs exclusively on repurposed electric vehicle batteries rather than newly manufactured cells.

The full 28 MWh of storage capacity at the site is derived from second-life EV packs that have been given a subsequent use in stationary storage. The company presents the project as a demonstration of second-life battery technology deployed at utility scale.

With commercial operations now underway, the announcement states that the facility is operating in commercial service on the ERCOT grid, making Bexar Martinez an example of repurposed EV batteries supporting grid-level storage rather than remaining confined to pilot or demonstration stages.

A Site Near San Antonio Inside CPS Energy's Footprint

Geographically, the project sits near San Antonio, placing it within one of the largest metropolitan areas in Texas. The announcement specifies that the facility is located within the service territory of CPS Energy, the municipally owned utility serving that region.

The commercial operation of the project marks its entry into active service on the ERCOT grid, where it will provide its 28 MWh of storage capacity in the form of grid services.

B2U's announcement did not elaborate on the specific commercial arrangements behind the facility or the duration of any grid service commitments associated with it.

What the Announcement Does and Does Not Cover

The confirmed points from B2U Storage Solutions' announcement, which was published on September 26, 2026, are these: the Bexar Martinez BESS project has started commercial operations; the facility is located in Texas near San Antonio; it sits within CPS Energy's service territory; it will deliver 28 MWh of grid services to ERCOT; and its battery fleet consists entirely of repurposed EV batteries.

Several details were not included in the available material.

The announcement provided no power rating in MW for the facility, no information on where the repurposed batteries originated, no identification of the counterparties purchasing the storage services, no interconnection timeline, and no description of the second-life battery supply chain supporting the site. Those specifics would require further disclosure from B2U Storage Solutions or its project partners.

The ERCOT Market Angle

ERCOT, the grid operator receiving the services from Bexar Martinez, manages the electric grid serving the majority of Texas.

The arrival of a second-life battery facility into commercial operation in this market is notable precisely because the site's storage capacity comes entirely from repurposed EV batteries, as stated in the announcement.

The central claim of B2U's announcement is Bexar Martinez's status as a commercially operating, second-life BESS. The company describes the project as demonstrating the deployment of second-life battery technology, and with commercial operations now begun, the facility is providing its 28 MWh of grid services on a going-forward basis.

As of the announcement date, no additional performance data, financial terms, or expansion plans for the Bexar Martinez site were included in the available material. This article will be updated as further information from B2U Storage Solutions or the project's stakeholders becomes available.