SDG&E’s Battery Project Continues to Advance Clean Energy Microgrids
March 2021
To deliver on our industry’s clean energy commitment, EEI’s member companies are forming domestic and global partnerships and are using innovative technologies to achieve deep carbon reductions while keeping electricity reliable and affordable. With international support, San Diego Gas and Electric’s (SDG&E’s) vanadium redox flow battery demonstration project is being extended. 

This battery was the first of its kind to be connected to the California energy grid to help support reliability and to maximize the use of clean energy at one of SDG&E’s substations. 

"Long-duration energy storage and microgrids are both key to helping California meet its clean energy, reliability, and resiliency goals. We need breakthrough technologies to achieve 100 percent renewable energy on our grid and to power microgrids during emergencies," said SDG&E CEO Caroline Winn. "SDG&E is proud to play a role in developing innovative solutions, like the flow battery technology, to help solve California's climate-related challenges." 

SDG&E and Sumitomo Electric launched the initial battery demonstration project in 2017 with support from Japan's New Energy and Industrial Technology Development Organization and the California Governor's Office of Business and Economic Development. 

The emerging battery technology is being tested to help achieve zero-emission microgrids – a tool to keep communities and critical facilities powered with clean energy during adverse weather conditions and Public Safety Power Shutoffs. The collaboration recently was extended through the end of 2021 to further test the battery's microgrid capabilities and to maximize its ability to support the grid with ancillary services such as voltage and frequency regulation. 

The battery began participating in the California Independent System Operator’s wholesale electricity markets in December 2018 and was used last summer to help minimize the impact of rotating outages during a record heatwave. 

"I'd like to express my deepest gratitude to GO-Biz, San Diego Gas & Electric, and NEDO for implementation of the Sumitomo flow battery in California,” said Hideo Hato, senior managing director of Sumitomo Electric. “This is a reliable, long-duration technology that offers a high degree of operational freedom and fire safety, using non-flammable and re-usable electrolyte. Based upon these advantages, I'm confident the flow battery contributes to grid reliability in California. I am determined to help California reach its clean energy goals. I look forward to continuing our partnership with San Diego Gas & Electric." 

To learn more, visit SDG&E’s website.​