Regional Inertia Estimation Using Actual Event Measurements: Florida Case

Conference · Sun Nov 30 23:00:00 EST 2025

DOI:https://doi.org/10.1109/NAPS66256.2025.11272260· OSTI ID:3009487

Dulal, Saurav ^[1]; Olama, Mohammed M ^[2]; Ekti, Ali Riza ^[2]; Stenvig, Nils ^[2]; Liu, Yilu ^[2]

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1. University of Tennessee, Knoxville (UTK)
2. ORNL

As inverter-based resources’ integration in power grids increases, their uneven distribution across the electrical network leads to the formation of local regions that are weakly coupled to the larger interconnection. This signifies the necessity of regional frequency dynamics investigation and analyzing various inertia metrics. This paper presents a practical methodology for estimating regional rate-of-change of frequency (RoCoF) using actual event recordings, which is then used to evaluate regional inertia. Florida (FL) is selected as the region of interest due to its distinct regional frequency dynamics and the rising levels of solar generation. We identify and analyze confirmed events from 2017 to 2024 that occurred in FL. The results indicate that FL contributes about 14% to the total inertia of the US Eastern Interconnection, which approximately matches its share of generation capacity. Results also highlight seasonal fluctuations in energy generation, which play a significant role in influencing inertia and thus the RoCoF levels. This emphasizes the importance of estimating regional inertia to enhance grid operations for a future that focuses on distributed generation.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Electricity Delivery and Energy Reliability (OE); USDOE
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 3009487
• Resource Relation: The 57th North American Power Symposium (NAPS 2025) - Hartford, Connecticut, United States of America - 10/26/2025-10/28/2025
• Country of Publication: United States
• Language: English