Southern Power retrofitting 640MWh of battery storage at two California solar power stations

LinkedIn
Twitter
Reddit
Facebook
Email
Image: Southern Power.

US wholesale energy provider Southern Power is adding battery energy storage to two solar sites in California.

Storage will be added to the company’s Tranquillity Solar Facility and Garland Solar Facility, with Southern Power – a subsidiary of the Southern Company – also announcing it has signed 20 year power purchase agreements (PPAs) with Southern California Edison (SCE) for the two sites.

At the 205MW Tranquillity Solar Facility in Fresno County California, a 72MW / 288 MWh energy storage system will be added, whilst at the 200MW Garland Solar Facility in Kern Country a 88MW / 352MWh storage facility will be added.

The energy storage components will provide flexibility to SCE and the California ISO (CAISO), enhancing grid reliability and enabling further renewable energy integration.

This article requires Premium SubscriptionBasic (FREE) Subscription

Try Premium for just $1

  • Full premium access for the first month at only $1
  • Converts to an annual rate after 30 days unless cancelled
  • Cancel anytime during the trial period

Premium Benefits

  • Expert industry analysis and interviews
  • Digital access to PV Tech Power journal
  • Exclusive event discounts

Or get the full Premium subscription right away

Or continue reading this article for free

“These projects will be two of the first co-located solar and storage projects operating in the California market,” said Southern Power president Bill Grantham, adding that the company was excited to be part of the effort to “enhance California’s grid reliability.”

“The addition of these storage resources to our clean energy portfolio is a great strategic fit for our business and will further position Southern Power to meet our customers’ needs as the energy industry continues to evolve.”

Both energy storage projects will be owned in partnership with AIP Management and Global Atlantic Financial Group, who already have existing ownership interests in the two facilities. Southern Power will be responsible for operating the storage, building on their operation of both solar sites since they went into commercial operation in 2016.

This story first appeared on PV Tech.

3 November 2026
Málaga, Spain
Understanding technology and supplier selection for Europe’s utility-scale PV market in 2027. PV ModuleTech Europe 2026 is a two-day conference that tackles these challenges directly, with an agenda that addresses all aspects of PV module, inverter and battery supplier selection; product availability, technology offerings, supply chain traceability, quality assurance, factory auditing, system reliability, and supplier bankability.

Read Next

October 26, 2026
Gingerah Energy has referred a 1GW data centre complex with a 5GWh BESS in Western Australia to Australia’s EPBC Act.
October 23, 2026
Tech giant Google and distributed energy resource (DER) platform Voltus have announced an expanded agreement to build a 1GW virtual power plant (VPP) in the US.
October 23, 2026
German home energy storage and virtual power plant (VPP) company sonnen GmbH, sold by gas major Shell in August, has filed for insolvency.
October 21, 2026
Spain-headquartered power electronics manufacturer Ingeteam has supplied power conversion systems (PCS) for around 65MW/130MWh of battery storage projects in Victoria, New South Wales (NSW) and South Australia.
October 20, 2026
US utility Dominion Energy plans to build 3.5GW of battery energy storage systems (BESS) over the next 20 years according to its recently filed integrated resource plan (IRP).