SDG&E and AES complete world’s largest lithium ion battery facility

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The unveiling of the new project in Escondido, California. Credit: Facebook, SDG&E

Utility San Diego Gas and Electric (SDG&E) and US-based storage provider AES Energy Storage, a subsidiary of AES Corporation, have completed what they claim to be the world’s largest lithium-ion battery energy storage facility in Escondido, California.

The 30MW/120MWh system is capable of storing enough energy for the equivalent of 20,000 customers for four hours. The two companies signed agreements to build two storage systems in August last year. The second system at El Cajon is 7.5MW in capacity. A total of 400,000 batteries were installed in nearly 20,000 modules in 24 containers.

The agreement came off the back of the California Public Utility Commission (CPUC) directing Southern California investor-owned electric utilities to fast-track additional energy storage options to enhance regional energy reliability last year in response to the Aliso Canyon gas leak.

John Zahurancik, AES Energy Storage president, said: “These two projects, including the world’s largest advanced energy storage site, are the latest proof of energy storage’s capacity to scale up and solve our most pressing grid issues in a short period.”

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Last year, Energy-Storage.News caught up with Brian Perusse, vice president of AES Energy Storage and Jim Avery, chief development officer of SDG&E, to discuss the unique challenges of the projects and the AES Advancion 4 energy storage platforms that were used.

By 2030, SDG&E expects to develop or interconnect more than 330MW of energy storage on the system. Last week, AES Corporation and investment manager Alberta Investment Management Corporation (AIMCo) agreed to acquire major US utility-scale solar developer sPower for an estimated US$1.58 billion.

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