SDG&E expands its microgrid and energy storage portfolio

Oct. 14, 2022
Microgrids and energy storage rescued California’s electric grid repeatedly this summer, and SDG&E is working to rapidly expand its portfolio of both.

Heatwaves and wildfires continue to strain California’s electric grid, and this summers’s record temperatures have once again put many parts of the state on the brink of rolling blackouts. Microgrids and energy storage systems have come to the rescue and helped to avoid power emergencies more than once this summer in San Diego Gas & Electric’s (SDG&E) services areas, and that’s one of the reasons the utility is working to rapidly expand its portfolio of both.

Breaking ground on the Tierrasanta microgrid

This week, SDG&E announced the start of construction on a new energy storage and microgrid project – one of four on its docket that will bring another 39 MW of battery capacity to its service area. The 10 MW Tierrasanta microgrid, located at the Elliott substation, will be able to power a fire station, a library that serves as a cooling center, the Tierrasanta Medical Center, and several of the area’s schools.

“Investing in innovative clean energy technology like the Tierrasanta Microgrid will bolster public safety while also bringing economic opportunity to local, family-owned businesses,” said San Diego City Council member Raul Campillo (District 7).

He added that extreme weather events, such as this summer’s heatwave, demonstrate how critical it is for the region to improve its resiliency.

Microgrids and energy storage deliver resilience

“Innovations like storage and microgrids are vital to building a more resilient electric grid that can extend the availability of renewable energy into peak demand hours and better prepare communities to manage through emergencies,” said Miguel Romero, said SDG&E vice president of energy innovation.

This summer’s heatwave forced SDG&E to rely on utility-scale battery storage systems for as much as 7% of its load during peak hours. Energy was provided both by the utility’s own 95 MW of storage, as well as from energy storage systems owned by third parties.

One of those third parties was the microgrid power plant located at Marine Corps Air Station (MCAS) Miramar, which came to SDG&E’s aid in August. The base’s microgrid ran for five hours, allowing the utility to provide continuous power to 300,000 San Diego area homes during a time of high grid demand.

SDG&E is rapidly expanding energy storage and microgrid capacity

The state of California has around 4,000 MW of battery storage capacity online.

SDG&E recently completed construction of a 40 MW energy storage project in Fallbrook, enough energy to power 25,000 homes. The facility is currently being tested and will ultimately be connected to the state’s grid allowing California Independent System Operator to distribute the energy as needed across the state.

SDG&E has more than 200 MW of utility-owned energy storage in development.

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About the Author

Kathy Hitchens | Special Projects Editor

I work as a writer and special projects editor for Microgrid Knowledge. I have over 30 years of writing experience, working with a variety of companies in the renewable energy, electric vehicle and utility sector, as well as those in the entertainment, education, and financial industries. I have a BFA in Media Arts from the University of Arizona and a MBA from the University of Denver.

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