Graph Trend Definitions Telemetered SCE: Sum of all QSE’s Telemetered SCE (uses “Left” scale). Regulation Deployed: Sum of all Regulation Ancillary Service. PLUS = increase generation, MINUS = decrease generation. (uses “Left” scale). Responsive Deployed: Sum of all Responsive Ancillary Service. Positive Only. (uses “Left” scale). Balancing:Balancing awarded: Sum of all QSE’s award. (uses “Left” scale) Spinning Reserve: Sum of all QSE’s telemetered Spinning Reserves. (uses “Left” scale.) Total Generation: Sum of all QSE’s “Total Generation” telemetered to ERCOT. (On some NOI’s this may include bilateral purchases/sells). (uses “Right” scale.) BPS & Dynamic: Sum of all QSE’s Base Power Schedules and Dynamic Schedules. Most QSE’s have one or the other, some have both. (uses “Right” scale). OLC “On-Line Capacity”: Sum of all QSE’s – Sum of Total Generation and Spinning Reserve as telemetered from each QSE. (uses “Right” scale). Obligation – Total Up Physical Obligation: Sum of all QSE’s. Sums for each QSE: Base Power Schedule, Dynamic Schedule, Regulation “UP” Physical obligation, Responsive Physical obligation, any Non-Spin that has been deployed, Balancing Energy Deployed and Frequency Obligation (QSE bias times frequency deviation). (uses “Right” scale). Excess: Difference between “OLC” and “Obligation”: Sum for all QSE’s. MINUS = QSE’s “deficit” (uses Right scale). Load Imbalance: Difference between “Total Generation” and the sum of “Base Power Schedules and Dynamic Schedules”. (uses “Left” scale)

ERCOT Totals Feb 24 06:00 to 08:00

Feb 25 06:00 to 08:00

Feb 25 08:00 to 10:00

Feb 25 10:00 to 12:00

Feb 25 12:00 to 14:00

Feb 26 06:00 to 08:00

Load Imbalance Feb 24 06:00 to 08:00

Feb 25 06:00 to 08:00

Feb 25 08:00 to 10:00

Feb 25 10:00 to 12:00

Feb 25 12:00 to 14:00

Feb 26 06:00 to 08:00

Total Governor Response Feb 24 06:00 to 08:00

Feb 25 06:00 to 08:00

Feb 25 08:00 to 10:00

Feb 25 10:00 to 12:00

Feb 25 12:00 to 14:00

Feb 26 06:00 to 08:00