A large investor-owned utility in the Southeast operates more than 80,000 miles of overhead distribution lines and serves approximately 9 million customers across a fast-growing service territory. Sustained demand growth—driven by new residential development, electrification, and economic expansion—has required the utility to add new circuits across an already dense distribution network.
Maintaining reliability at this scale is not optional. Every operational decision carries systemwide impact.
Challenge
As the utility added more circuits to meet growing demand, fault activity began to increase across the network. Protective devices were doing their job—reclosers operated correctly and cleared faults—but the utility faced a new operational reality:
- Faults were occurring more frequently as network density increased
- Many faults were momentary, but still required investigation
- Crews were being dispatched without clear insight into root cause
- Reliability metrics, including SAIDI, began to feel pressure
The problem was not protection failure. It was lack of visibility into fault behavior as the system grew more complex.
Without understanding why faults were happening—or whether they were isolated or systemic—the utility was forced into a reactive posture that increased O&M costs and operational risk.
Solution
To close this gap, the utility deployed Electrical Grid Monitoring (EGM) line sensors in combination with reclosers, creating a more observable and intelligent distribution network.
As new neighborhoods were commissioned, the utility standardized the deployment of:
- Reclosers for protection and isolation
- EGM line sensors placed strategically along feeders and laterals
- EGM analytics software to turn raw fault data into operational insight
EGM’s platform provided detailed, real-time visibility into each fault event, capturing:
- Fault magnitude
- Direction
- Phase involvement
- Event patterns across circuits
This intelligence allowed engineering and operations teams to move beyond fault clearing and into root cause analysis at scale—something that was previously impossible across such a large network.
With EGM in place, the utility fundamentally changed how it responded to fault activity:
- Cleared faults no longer automatically triggered truck rolls
- Crews were dispatched based on data, not uncertainty
- Engineering teams identified recurring fault patterns tied to load growth and circuit expansion
- Maintenance practices evolved from routine investigation to targeted intervention
Instead of reacting to individual events, the utility gained system-level awareness of how growth was affecting reliability.
Results
The operational improvements delivered clear, defensible outcomes within the first year:
- Up to 25% reduction in truck rolls, driven by fewer unnecessary investigations
- 7.5 SAIDI minutes saved across the system in a single year
- $3.7 million in O&M savings, with no compromise to safety or protection
- Improved reliability performance as new load and circuits continued to come online
These results were achieved while the utility continued to grow, proving that reliability and expansion do not have to be tradeoffs.
Benefits
For large IOUs, the challenge is no longer whether faults can be cleared—it is whether the grid can be understood as it operates under increasing load and complexity.
EGM helps utilities answer critical questions:
- Are faults isolated events or early indicators of stress?
- Where is growth changing fault behavior?
- Which events require action—and which do not?
By delivering practical, real-time grid intelligence, EGM enables utilities to operate with confidence as their networks evolve.
Conclusion
By adding situational awareness where it mattered most—downstream of protective devices—the utility transformed how it understood and responded to fault activity. What was once a reactive investigation process became a data-driven operating model grounded in real-time insight.
This deployment demonstrates how targeted grid visibility can deliver meaningful reliability improvements at scale, without requiring an overhaul of existing infrastructure. As distribution systems continue to grow in size and complexity, visibility is no longer optional—it is foundational to sustaining performance.
Bring Visibility to Your Distribution Network
Learn how Electrical Grid Monitoring helps utilities turn fault data into actionable insight—supporting reliability as systems grow and evolve.