Energy Storage

CPS Energy Signs MOU To Deploy Used EV Batteries For Storage

CPS Energy in San Antonio, Texas, has signed a memorandum of understanding (MOU) to test recycled electric vehicle batteries to store energy produced by solar panels.

Under the MOU, signed with OCI Solar Power and Hyundai Motor Group, the parties aim to install an energy storage system by September 2022. The storage system was developed by Hyundai, which is also providing the used, or “second life,” batteries at no cost. OCI Solar Power will procure some of the storage system components and supervise construction. CPS Energy will operate the storage system. All the partners will share data from the project.

After about seven or 10 years of use, a lithium-ion battery is no longer suitable to power an electric vehicle, but the battery still has enough capacity to be used in a stationary storage application.

Stationary storage powered by used electric vehicle batteries could exceed 200 gigawatt-hours (GWh) by 2030, according to a 2019 analysis by McKinsey & Co.

“We are taking a very important step in advancing our technology in regards to battery storage, thanks to this new collaboration with OCI Solar Power and the Hyundai Motor Group,” Fred Bonewell, chief operating officer at CPS Energy, said in a statement. “Evaluating these innovative technologies is key to discovering the next firming capacity that would be needed to replace fossil fuels.”

CPS Energy already has a 10 megawatt (MW), 1 hour duration battery storage system it installed about two years ago as part of a 5 MW solar facility. The $16.3 million project was done in partnership with the Southwest Research Institute, which provided the land.

The project aims to explore the potential for using batteries to shift solar power output to times when it is most needed on the grid. The solar-plus-storage project was also supported by a grant from the Texas Commission on Environmental Quality.

At 500 kilowatts (kW), the newly announced project using second life batteries will be much smaller than the solar-storage project. And while it may connect to a CPS solar project eventually, the scope of the new project will likely be wider than solar shifting.

“We are calling it a small scale limited deployment project,” Jonathan Tijerina, senior director of business and economic development at CPS Energy, said. The battery system will likely do “a little bit of everything. We’ll try a lot of different scenarios,” he said, adding that the MOU is still in the early stages and one of the next steps will be to finalize the use cases for the new battery system.

The MOU will also evaluate the recycled batteries over the three to five year life of the project to assess how long the batteries can perform.

Late last year, CPS Energy issued a request for proposals to add up to 900 megawatts (MW) of solar, 50 MW of energy storage and 500 MW of firming capacity as part of its FlexPOWER Bundle initiative designed to replace some aging generation capacity and introduce new technologies as firming capacity to help ensure energy reliability for San Antonio.

The FlexPOWER program is part of CPS Energy’s broader Flexible Path resource plan that aims to move the San Antonio area to a decarbonized future by 2050 or sooner. The new second life battery project fits within the framework of CPS Energy’s Flexible Path plan, Tijerina said.

As of October 2020, CPS Energy had over 500 MW of solar power and more than 1,000 MW of wind power.