There have been 12 billion-dollar weather or climate disasters in the United States as of July 2023, and electric utilities are bracing for further impact. The growing threat of increasingly severe weather due to climate change will continue to test distribution grid reliability and resilience. At the end of this storm season, utilities will be able to see clearly which efforts have succeeded in improving resilience and reliability and which efforts they need to improve.
Some electric utilities will see relative improvements in reliability and resilience and will report their reliability metrics, as scheduled, to the regulatory bodies that govern them. Of particular focus is their system average interruption duration index (SAIDI) numbers. However, we must consider that these metrics exclude major storm events, creating what is called a resilience gap.
A growing resilience challenge
This resilience gap is explored in a recently updated study by S&C Electric Company. Not surprisingly, the research shows that resilience decreases when weather events are included in the calculation. For example, the SAIDI trend line reflects 33.5 minutes per year through 2021 when including major events, yet only 1.9 minutes in annual growth excluding major events. This 32-minute difference is known as the “resilience gap” because excluding weather events makes the grid appear more resilient than it is. But any electricity user would agree: no outage is acceptable. This means that, with extreme weather becoming more frequent, more attention and investment in the distribution grid is needed to improve resilience during days both sunny and stormy.
Managing grid capacity for transportation electrification
This increase in major weather events runs parallel to other growing complexities on the grid, such as electric vehicle (EV) penetration. Next year, for example, GMC plans to release a new set of electric trucks to the public for purchase. The move toward brand-agnostic charging infrastructure, such as Ford and GM drivers having access to Tesla chargers, will remove another barrier toward EV adoption and spur growth.
But where will this power come from? Additional capacity must be created on the distribution grid, and the time for investment is now. As electric utilities continue to look for ways to address weather events and the capacity challenges and opportunities of electrification, they must look to distribution to support grid reliability and resilience.
“In the next three years, I expect we’re going to see this clash of climate change, electric vehicles and people wondering why they can not charge their cars for multiple days,” said Mike Edmonds, chief commercial officer for S&C. “Customers expect that the power will always be on.”
Utilities will need to help manage customer expectations while also providing the transparency needed to convince regulators that reliability investments are worthwhile. Florida Power & Light Company (FPL), Florida’s largest power utility and a subsidiary of NextEra Energy, is one of a few utilities that have successfully articulated the value of their reliability improvements and received support from their local regulatory commission.
“I recommend all investor-owned utilities look at those rate cases,” Edmonds said. “The same FPL playbook was used by executives at Gulf Power to improve SAIDI from 120 minutes to 41 minutes, so there is a lot to be gained from studying how utilities are managing their grid reliability and resilience improvement efforts and articulating these efforts to the public.”
Preparing the utility of the future
Building the grid of the future starts with improving reliability, reducing the resilience gap and creating better end-user experiences. It will require new technology and practices that allow utilities to revolutionize their traditional approaches. Distribution automation and other smart grid technologies, for example, are being deployed to create a more resilient distribution grid, helping electric utilities to save time and reduce costs.
Utilities are also making their distribution systems more resilient by undergrounding overhead lines, replacing live-front equipment with dead-front equipment and installing concrete poles instead of wooden ones. Other utilities, such as Eversource, a northeastern U.S. energy company, are hardening their overhead systems using fault-testing technology that increases the resilience of their distribution systems and mitigates outages. With these improvements, utilities have made their overhead systems just as resilient and high-performing as underground systems.
S&C Electric Company, a global provider of equipment and services for electric power systems, is helping utilities push the boundaries with new technology. The company recently introduced its EdgeRestore® Underground Distribution Restoration System to bring self-healing technology to the grid edge and help accelerate these efforts.
With extensive damage from storms, crews often work long hours to find the underlying issues of outages and repair them, adding costs and time to restoration efforts. On underground lines, this can be particularly challenging. S&C’s EdgeRestore system reduces the impact of permanent outages from hours to 60 seconds or less, helping to quickly identify and isolate faults, restore power and improve reliability and resilience on underground residential lines. Visit sandc.com/EdgeRestore to learn more.
