The unofficial ERCOT peak for October was 59,193 MW. There were six frequency events in October. PMU data indicates the ERCOT system transitioned well in each case. There were four instances where Responsive Reserves were deployed, all of which were the result of frequency events. There were seventeen RUC commitments in October. Seven in the Northern region, seven in the Southern region and three in the Coastal region. All were due to local congestion. The level of reportable SCED congestion decreased in October. This congestion was due primarily to planned outages and area load/gen patterns. There were thirteen days of activity on the Generic Transmission Constraints (GTCs) in October. This included one day of activity on the Laredo GTC, nine on the Zorillo – Ajo GTC and three on the Valley Import GTC. There were no significant system events for the month of October. ERCOT Applications performed well throughout the month. There were no ERCOT related application performance issues. The ERCOT Interconnection experienced six frequency events in October, all of which resulted from Resource trips. The average event duration was approximately 0:04:42. When analyzing frequency events, ERCOT evaluates PMU data according to industry standards. Events with an oscillating frequency of less than 1 Hz are considered to be inter-area, while higher frequencies indicate local events. Industry standards specify that damping ratio for inter-area oscillations should be 3.0% or greater. All events listed below indicate the ERCOT system met these standards and transitioned well after each disturbance. Reported frequency events will include both frequency events where frequency was outside the range of 60±0.1 Hz as well as those determined to be Frequency Measurable Events (FME) as defined by BAL-001-TRE-1. Delta Frequency is defined as the difference between the and post-perturbation frequency. The Duration of Event is defined as the time it takes for the frequency to recover to lesser/greater of the frequency at the time of the frequency event (t(0) or “A-point”) for low/high-frequency events, respectively. Further details on FMEs can be found in the MIS posted BAL-001-TRE-1 PDCWG Unit Performance reports. A summary of the frequency events is provided below: Date and Time Delta Frequency Max/Min Frequency Duration of Event PMU Data Comments
Bevo Substation - Asherton 138 kV Hamilton Road - Maverick 138kV 320 $4,635,315 Orange Grove Switching Station - Lon Hill 138 kV Lon Hill - Smith 69kV 4186 $4,156,156 16TPIT0026 Rio Hondo 345_138_1l 345/138 KV Aderhold Sub - Elsa 138kV 121 $4,047,071 Falcon Seaboard - Midland East 345 kV Glenhaven - Odessa 138kV 70 $3,753,436 Base case North to Houston (Houston Import) 92 $3,656,328 4485, 3937, 3950 (a,b) Calaveras – Hotwells & Laredo1 138 kV Calaveras - Streich 138kV 738 $3,654,243 Falcon Seaboard to Morgan Creek Ses 345 kV Crmwd 8 Tap - Glenhaven 138kV 65 $3,638,593 ERCOT The unofficial ERCOT peak load for the month was 59,153 MW and occurred on October 12th during hour ending 17:00. This demand value was a record peak for ERCOT. None. None. PMU ERCOT analyzes PMU data for any significant system disturbances that do not fall into the Frequency Events category reported in section 2.1. The results are summarized in this section once the analysis has been completed. There were no reportable events in October. TRE/DOE 10/13/15 - ERCOT issued a Media Appeal for energy conservation as a precautionary measure due to a potential Rio Grande Valley Import limit exceedance. None. SPS None. None.