Reducing the impact of power outages is increasingly complex. Electricity demand is soaring. Energy resources are becoming more distributed. Extreme weather events are more common and less predictable. More than ever, intelligent grid automation is vital to improve grid service.
The U.S. Energy Information Administration (EIA) projects American power demand will rise to an unprecedented 4067 billion kWh in 2024 as economic growth and electrification continue. At the same time, the EIA reports climate change is causing more frequent and intense heat waves, droughts and downpours, and the average duration of a power outage in the U.S. grew from approximately 3.5 hours in 2013 to more than seven hours in 2021.
Establishing a fault location, isolation and service restoration (FLISR) system turns sustained outages into momentary ones. Using feeder automation software, utilities are leveraging real-time data to detect distribution system disturbances and automatically reconfiguring their system for significant reliability improvements. Carroll Electric Membership Corp. (EMC) in western Georgia can attest to the benefits of feeder automation technology. Every dollar it invested in grid automation software has helped to continually reduce outage durations for the members it serves.
Following the success of its three-phase automation projects, the utility is applying the proven model to its single-phase network to set a new standard for a smarter, healthier grid. The utility’s long-term FLISR system, including software and electronic devices, is supporting a remarkable 38% reduction in outage durations. The utility anticipates an even greater reduction over time.
A Successful Strategy
Carroll EMC distributes approximately 1 billion kilowatt-hours of electricity annually across seven counties, 54,000 accounts, 5500 miles (8851 km) of distribution line and 25 distribution substations. The utility’s electric distribution system is designed, constructed, maintained and operated to maximize reliability at a reasonable cost for customers. However, with a quickly growing membership and expansive service area, it became a difficult and time-consuming process to manually respond to system outages.
The electric cooperative sought to deploy a FLISR system to minimize the impact of grid interruptions. One of the utility’s primary goals was to implement a feeder automaton solution that would give it complete management over control schemes, so it could easily adjust the system to grow alongside the needs of its infrastructure. To reduce complexity and costs, the coop needed the grid automation technology to operate seamlessly with its legacy equipment from many different manufacturers.
Carroll EMC’s strategy was to focus first on its three-phase feeders, which contributed significantly to overall outage durations across the utility’s network. Next, the coop would expand this intelligent and automated approach to a portion of its single-phase lines located in residential areas to further reduce outages.
The project kicked off in 2012 and the first two phases focused on the three-phase network, including the installation of 192 intelligent devices. The third phase addressing single-phase automation began in 2021 and continued into 2023, with about 60 intelligent devices installed[CP1] . To date, nearly 250 intelligent electronic devices have been deployed across the utility’s network, working with the Eaton feeder automation software to automatically isolate damaged sections and restore power to as many people as possible.
Overall, the utility’s strategy is paying off, and it is minimizing the number of members impacted during an outage and preventing entire neighborhoods from growing dark. Since the start of its distribution automation program, Carroll EMC has continually reduced its system average interruption duration index (SAIDI) year-over-year. The utility anticipates a 41% reduction in outage duration, including a 34% reduction from the three-phase deployment and an additional 7% reduction from the single-phase project.
In 2022 alone, Carroll EMC calculated the feeder automation solution reduced outage time by about 75 minutes for members.
In the past, the coop required an entire crew of personnel to manually isolate an impacted circuit and restore service. With the feeder automation platform, all stages of the outage isolation process are now completed automatically from a central location, transforming Carroll EMC’s approach to managing outages and improving service for members.
Carroll EMC is realizing powerful benefits from the feeder automation platform that go far beyond advanced outage response and management. It also uses the software to do the following:
- Quickly detect and isolate faults, so unaffected load sections can be restored by feeders
- Automatically detect loss of voltage situations, so impacted line sections can be isolated from the feeder and unaffected sections can be restored
- Continuously monitor and track historical loading on the system to prevent overload events
- Easily add and remove devices using a standardized interface without the need to reprogram reconfiguration algorithms.
Additionally, a simulator, communications dashboard and post-event reporting capability are built into the platform to help Carroll EMC turn distribution automation into an integrated process driven by real-time data. These robust, standardized tools empower the utility’s engineers to easily change automation settings in minutes rather than months by eliminating costly custom programming and trial-and-error debugging.
Further, the software platform maintains a complete log of each device operation and changes in device status. During any event, the steps are traced through each automation logic decision with supporting preprogrammed logic comments for actions based on available data. All entries are time- and date-stamped and can be synchronized with device sequence-of-event records.
It is vital the utility fully understands the events that occur across its electric distribution system to continually improve the quality of service. This detailed event logging enables staff to easily investigate and audit events that occur across the entire service area from one centralized location, which mitigates the need for personnel to expend valuable time and labor performing field investigations.
Flexibility, Scalability, Interoperability
Carroll EMC values the flexible and scalable architecture of the FLISR system, which simplifies integration and improves system performance. Additionally, the feeder automation software can operate both integrated with or completely independent from the supervisory control and data acquisition (SCADA) system, which enables Carroll EMC to upgrade its legacy SCADA system independently, without impacting its ability to reduce outage times during the transition period.
Many distribution automation solutions have limited functionality or require complex third-party engineering. Following installation, these systems are often difficult to modify because of limited configurability or the need to recontract with the original engineering vendor. As a result, both vendors and utilities tend to approach feeder reconfiguration as a project rather than an integrated process.
To avoid these issues, Carroll EMC recommends utilities prioritize distribution automation solutions that support the easy addition and removal of intelligent devices using a standardized interface without reprogramming of reconfiguration algorithms. By using these interoperable platforms, the number of sources and switching devices that can be automated is only limited by the physical load flows of the power system and communications infrastructure.
Additionally, interoperable distribution automation solutions allow for virtually any existing control and standard communications protocol to be integrated into automation systems, eliminating the need for additional hardware or protocol converters. This feature, alongside compatibility with existing legacy controls and the next generation of controls, can help utilities to meet requirements today and challenges tomorrow — with the added ability to expand feeder automation programs across single- and three-phase lines seamlessly.
A More Intelligent Future
Today, there is an enormous opportunity to transform U.S. distribution networks to support an increasingly electrified world with far more reliable power.
As extreme weather and natural disasters reach new extremes, there will be more service interruptions and safety concerns for the utility workers who need to repair or replace equipment. And as the world electrifies, the importance of maintaining a resilient energy supply only grows.
The distribution network can work harder and do more to power an electrified, resilient future. Limiting the repercussions and frequency of grid outages is a major step in this journey that can be simplified by establishing a foundation of grid intelligence.
Utilities across the U.S. are prioritizing investments in modern automation capabilities that help to balance the grid, reduce interruption frequency and duration and remotely isolate and manage faults. Working closely with utilities, industry suppliers are helping to set the stage for success by developing creative, interoperable smart grid technologies that drive operational efficiency and simplify resilience.
Jasmin Giroux-Maltais is an electrical engineer with more than a decade of experience in delivering intelligent automation solutions to customers in Canada, the U.S. and Europe.
James Layton is a seasoned electrical engineer, serving as vice president of engineering and technology at Carroll Electric Membership Cooperative. With nearly two decades of experience, he has played a pivotal role in implementing innovative technologies and solutions to enhance the reliability and sustainability of the coop’s electric grid that powers more than 55,000 homes and businesses.