San Diego Gas & Electric (SDG&E), in collaboration with AES Energy Storage, has unveiled a new 30MW energy storage facility in California, US.

Claimed to be the largest energy storage system in the world, the facility can store up to 120MWh of energy, which is equivalent to power about 20,000 households for up to four hours.

The energy storage project was undertaken by SDG&E in response to directions given by the California Public Utility Commission (CPUC) to speed up the process of installing additional energy storage options.

SDG&E contracted AES Energy Storage to build two lithium-ion battery energy storage projects with a total capacity of 37.5MW. 

While a 30MW facility was built in Escondido, California, a smaller 7.5MW energy storage system has been installed at El Cajon.

Featuring batteries similar to those used in electric vehicles, the energy storage facilities includes about 400,000 batteries installed in nearly 20,000 modules and placed in 24 containers.

SDG&E president Scott Drury said: “San Diego County is a community of leadership and innovation, so it is only fitting that this community should receive the benefit of this unique project.

“For more than a decade, SDG&E has been at the forefront to deliver results consistent with state and local clean energy and carbon emission goals.  These projects affirm our commitment to deliver clean energy to customers and to provide a more reliable power supply to our electric grid when it is most needed.”

AES Energy Storage president John Zahurancik said: “SDG&E is a leader in providing clean, reliable power to their customers, and we’re honored that they chose Advancion energy storage to serve their needs.

“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."

SDG&E expects to develop or interconnect over 330MW of energy storage facilities by 2030.

Image: SDG&E official at inaugural of the energy storage system. Photo: Courtesy of San Diego Gas & Electric.