Challenge
Extreme weather conditions can cause power outages, or electric utilities may decide to temporarily de-energize parts of the power grid to maintain safety. In California, winds, dry conditions, and wildfires are of particular concern.
Microgrids are one way to make the grid more resilient. Even during a broader outage, microgrids maintain electric service to community hubs and critical customers, such as hospitals.
But it’s a challenge to protect and control multi-customer microgrids because such microgrids may have many sources with widely varying properties, spread out across the system.
Collaboration
Pacific Gas and Electric Company, a subsidiary of PG&E Corporation, is a combined natural gas and electric utility serving more than 16 million people across 70,000 square miles in Northern and Central California. The company is a pioneer in developing new technology to meet customer needs in the face of extreme weather events.
Sandia National Laboratories has decades of experience with microgrids, including simulation, computer modeling, and control and protection. Its experience extends from military bases to large cities, with the work tied to Sandia’s energy security mission.
“This collaboration between PG&E and Sandia was initiated to utilize their expertise and research in inverter modeling, power system simulations, and controls for microgrids. Having a research partner like Sandia allows the utility to focus on technology development and yields a powerful R&D combination to solve real world engineering challenges.”
– Franz Stadtmueller
Pacific Gas and Electric Company
Solution
In this project, multi-customer, multisource microgrids are being studied to better understand their dynamic behaviors, determine how best to use the tools provided by the latest interconnection standards in such systems, ensure that these systems can remain properly controlled and protected, and identify limits and “rules of thumb” that can be broadly applied to this kind of system as they are deployed in more communities.
Impact
With resilient local microgrids, the power can be kept on for more utility customers, even during weather-driven outages. Situations which previously led to long outages might now create only momentary interruptions. Once demonstrated in California, the new knowledge, practices, and tools developed by this Sandia-PG&E partnership can also be applied elsewhere to make the grid more resilient.