Austin Energy signs a 200-megawatt battery deal with Jupiter Power. The council approved up to $320 million in July

Austin Energy has signed an agreement with Jupiter Power for up to 200 megawatts of battery storage at the company's existing site in Austin, the city announced Oct. 28. The two-hour batteries are expected to begin operating in 2030.

Batteries matter to Austin Energy customers because they can store power when it is cheap and release it during the hottest, most expensive hours on the Texas grid. The city says the deal brings the utility's battery portfolio to 340 megawatts, above the 300-megawatt target for 2030 in its Resource, Generation and Climate Protection Plan.

What the city announced

According to the release, Austin Energy issued an all-resource request for proposals in November 2025. Jupiter Power already has a contract with the utility for a 100-megawatt battery expected online by the end of 2027, and it bid additional batteries at the same Austin site. The release says Austin Energy will not pay to build or maintain the project.

"Battery storage is a crucial tool for balancing our grid," General Manager Stuart Reilly said in the release.

What our records add

The council approved the money in July. The deal is a capacity agreement: Jupiter Power builds and runs the batteries, and Austin Energy pays for the right to use them. On July 23, the council approved an agreement with Balcones Ridge Resiliency II, a Jupiter Power subsidiary, for up to 200 megawatts at up to $16 million a year for up to 20 years, or a maximum of $320 million. It passed on consent, 10-0, with one member absent. The Electric Utility Commission reviewed it first. According to the staff backup, costs under battery agreements are recovered the same way as power purchase agreements, through the Power Supply Adjustment charge on customer bills.

The first 100 megawatts. In July 2025, the council unanimously approved Jupiter Power's first agreement, through Balcones Ridge Resiliency, for up to 100 megawatts at up to $14.4 million a year, or $288 million over 20 years.

A deal that fell through. In May, the council approved a 100-megawatt, two-hour battery agreement with OCI Energy, worth up to $8.25 million a year. At the time, staff said it would bring the utility's pipeline to 240 megawatts, well past an earlier 125-megawatt goal. The July backup says Austin Energy first favored OCI's project for geographic diversity, but the two sides could not agree on commercial terms, so staff recommended Jupiter Power's larger project instead.

Smaller batteries, too. In April, the council approved up to 40 megawatts of distributed batteries from Base Power, at up to $4.08 million a year for 10 years. Asked by Council Member Mike Siegel in July whether those counted toward demand response, Chief Operating Officer Lisa Martin said they would be treated more like a dispatchable resource counted toward the battery goal.

Add it up and the 340 megawatts in the city's release matches the council's approvals: Jupiter Power's 100 and 200 megawatts, plus Base Power's 40.

What two-hour means. In May, staff explained that a 100-megawatt, two-hour battery can deliver 100 megawatts for two hours, or less power for longer. Austin Energy's average daily demand is around 2,000 megawatts, with peaks around 3,100.

What's next

Jupiter Power's first Austin battery is due by the end of 2027 and the new one in 2030, according to the city. Separately, the council votes Nov. 5 on authorizing up to $695 million in Austin Energy revenue bonds, which are repaid from utility revenue rather than property taxes. Our Nov. 5 agenda guide explains that item.