San Diego Gas & Electric will use a $4.5 million federal grant to upgrade the Borrego Springs microgrid with new technology so it can operate on completely clean energy, the utility announced Friday.
The grant, from the U.S. Department of Energy's Solar Energy Technologies Office, will provide funds to purchase smart power inverters, controls and an energy management system. The new devices will improve energy reliability, stabilize the microgrid and help it become 100% renewable.
A microgrid is a mini power grid and may include a power source like solar energy, an energy storage component and controls and switches that allow it to operate independent of or parallel to the larger grid. The Borrego Springs microgrid is the first such utility-owned grid in the nation.
RELATED: SDG&E's 50-Year Contract With San Diego Expires In January. So, What's Next?
"This grant award comes at a pivotal time for our customers, our company and the next evolution of microgrid technology," said Will Speer, vice president of electric engineering and construction for SDG&E. "Microgrids are one of the tools to enhance community resiliency and maintain energy service during emergencies. With the smart grid technology that we will incorporate into the microgrid, we are confident that this facility can become a model for future clean energy microgrids."
The Borrego Springs microgrid began operations in 2013 after SDG&E saw an opportunity to improve energy resiliency for the approximately 2,800 people in Borrego Springs — a remote desert town subject to extreme heat and monsoonal weather. Until then, the town relied on a single transmission line and distribution circuit for its power. The microgrid is connected to a local 26-megawatt solar field — owned by a third party — two battery storage systems, two generators and an ultracapacitor to keep power flowing to the town during emergencies and planned outages on the larger grid.
RELATED: San Diego Set To Solicit Bids On New Utility Franchise Deal
"This is great news for Borrego Springs, especially during emergencies like severe weather," said County Supervisor Jim Desmond. "It's important for San Diego County that we continue to move towards a healthier and more sustainable future."
Due to unstable voltage conditions and solar energy output fluctuations, it is challenging to operate the microgrid using 100% clean energy. The new inverter, controls and energy management system will help address these challenges and transition the microgrid to a true 100% clean energy facility.
SDG&E operates two microgrids — including the Borrego Springs location — within San Diego and southern Orange counties. The company is currently constructing four additional microgrids set to be completed in 2020 and 2021 as part of its Wildfire Mitigation Plan.