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

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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.

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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.

“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.

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