Two years ago, a new vanadium flow battery helped support California’s energy grid and keep it safe from additional wildfire outages. Now, the battery is making news at a San Diego Gas & Electric (SDG&E) substation as the first of its kind to use the emerging flow technology with microgrids to power communities and critical facilities with zero-emissions energy during adverse weather and public safety power shutoffs.
The utility started research on the battery technology in 2017. Collaborating with partners from a Japanese technology and industry group, the California Governor’s Office of Business and Economic Development (GO-Biz) and Sumitomo Electric, they continue to evaluate the vanadium flow battery’s microgrid capabilities and study its ability to support the grid with other services such as voltage and frequency regulation.
Unlike the more widely used lithium-ion batteries, vanadium flow batteries contain tanks of liquid electrolytes and pumps. They last longer and may degrade less from repeated charging cycles over time than other chemical battery technologies.
The California Independent System Operator’s wholesale electricity markets used vanadium flow batteries in December 2018 and again in the summer of 2020 to help minimize the impact of rotating outages during a record heatwave.
The collaboration working with SDG&E is continuing its research to determine if flow battery technology can lower the delivery costs of reliable energy to customers, add more renewable energy to the mix and increase grid operation flexibility. The collaboration’s project extends until the end of 2021.
“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% renewable energy on our grid and to power microgrids during emergencies,” said Caroline Winn, CEO of SDG&E. “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.”