The world’s largest single-phase battery is now online


Axium Infrastructure and Canadian Solar’s subsidiaries of Recurrent Energy and CSI Energy Storage announced the two have installed and activated what they are calling the world’s largest single-phase energy storage facility. Named Crimson Storage, the site holds 350 MW / 1400 MWh of standalone battery energy storage, delivering flexible power to California’s grid.

The project is held by a fund managed by Axium (80%) and Recurrent Energy (20%). CSI Energy Storage operated as the turnkey system integrator of the project, delivering engineering, procurement, and construction (EPC) services. The EPC will continue to provide long-term operational support for the site.

“The Crimson Energy Storage project epitomizes California leadership – clean energy, innovation, and economic development through good, union jobs. We’ve been laser focused on quickly bringing projects like this online to achieve our goal of a 100% clean energy grid. Congratulations to the people across the public and private sectors who are responsible for bringing this major project online to the benefit of all Californians,” said California Governor Gavin Newsom.

On average, the project is expected to store and dispatch enough electricity to power more than 47,000 homes each year. It is estimated that Crimson Storage will offset 275,000 tons of carbon dioxide emissions as compared to natural gas fired turbines.

During construction, the project employed about 140 union workers, including International Brotherhood of Electrical Workers, International Union of Operating Engineers, Laborer’s International Union of North America, and the International Association of Bridge, Structural, Ornamental and Reinforcing Iron Workers Union. It is expected to bring about $30 million in property tax revenue to the local community over the life of its operation.

The project is located in the California desert on Bureau of Land Management (BLM) lands. BLM approved the project in May 2021, marking the first standalone energy storage project to be approved on BLM lands under the Biden-Harris administration.

Image: Recurrent Energy

Image: Recurrent Energy

“The project represents another major step forward in the Biden-Harris administration’s goal of a carbon pollution-free power sector by 2035. We look forward to supporting additional projects like Crimson Storage that ensure responsible energy development on BLM lands,” said Karen Mouritsen, BLM California state director.

Upon activation, Crimson Storage became the largest active single-phase storage project in the world, and second-largest energy storage project currently in operation of any configuration. The project holds two long-term contracts with utilities Southern California Edison and Pacific Gas and Electric. Both contracts are part of reliability mandates made by the California Public Utilities Commission (CPUC).

  • Southern California Edison: 200 MW / 800 MWh 14-year and 10-month contract with Southern California Edison under a full tolling agreement.
  • Pacific Gas and Electric Company: 150 MW / 600 MWh 15-year contract with Pacific Gas and Electric Company for Resource Adequacy only; Recurrent Energy and Axium will operate the battery system in the California wholesale power market.

“Recurrent Energy began developing Crimson Storage and our larger energy storage pipeline in 2015 when no large-scale storage projects yet existed. Last year, we started bringing these projects to fruition also thanks to our CSI Energy Storage team. Today we celebrate how far we have come in delivering the much-needed flexible generation that will support the U.S. and California’s transformative climate goals,” said Shawn Qu, CEO of Canadian Solar.

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