NOTICE DATE: September 9, 2025

NOTICE TYPE: M-D082925-02 Operations

SHORT DESCRIPTION: Support requirements and details leading up to the live production two-hour test for RTC+B closed-loop frequency control on September 11, 2025 between 10:00-13:00

INTENDED AUDIENCE: All Qualified Scheduling Entities (QSEs) with Resources

DAYS AFFECTED: September 10-11, 2025

LONG DESCRIPTION: This notice is to provide high-level timelines and communications expectations for the September 11 live production RTC+B closed-loop testing and to request supporting contact information from QSEs with Resources.  Although the ERCOT Control Room will manage the test with Hotline calls, ERCOT will also require close support and communication leading into and during the test in the following three manners:

First is an additional Market Trials call: ERCOT is hosting an additional market trials preparations WebEx on September 10, 2025 from 10:00 am - 11:00 am (9/10 RTCB Market Trials Preparation for Production LFC Test Webex).

Second is a secure WebEx: ERCOT sent an email yesterday directly to all Authorized Representatives (AR), Backup Authorized Representatives (BAR), and RTC+B Accountable Executives (RTC+B AE) with the details of the secure WebEx that ERCOT will use to coordinate with QSE staff leading up to the closed-loop test.  If you are supporting the test and have not received this WebEx information, please contact your AR/BAR/RTCB-AE first, and if not successful then contact RTCB@ercot.com if you need assistance.  For this WebEx, ERCOT prefers only two or three participant connections from each company (to keep the population of attendees limited).  These participants should be staff that can provide EMS, AGC, SCADA applications cutover/cutback status and/or resolve any QSE telemetry and market submissions issues for the real-time Load Frequency Control (LFC) test. 

Third is a request for QSEs' appropriate contact phone numbers: ERCOT is requiring that each QSE provide phone numbers as a contact list in case ERCOT observes any issues to be resolved related to the following three areas between September 10, 3:00 pm and September 11, 1:00 pm:

        Telemetry Contacts: Primary and back-up names and phone numbers

        EMS/ SCADA/AGC Applications Contacts: Primary and back-up names and phone numbers

        Market Submissions Contacts: Primary and Back-up names and phone numbers

Please send the contact list to RTCB@ercot.com.

Below is the high-level summary of ERCOT expectations and timeline of support:

• On September 10, 2025:
  • By 3:00 pm, QSE should have updated RTC+B systems with parallel production data for each Resource in their September 11, 2025 portfolio:
    • Current Operating Plan
    • Ancillary Service Offers (ensure they are not set to expire before test and are in alignment with $0/$2,000 offer guardrail requirements)
    • Energy Offer/Bid Curves (ensure energy offer/bid are the same as production price and quantity)
  • ERCOT is targeting initial outreach at 4:00 pm to QSEs on any observed issues
  • ERCOT is targeting next outreach at 7:00 pm to QSEs on any observed issues
• On September 11, 2025
  • ERCOT starts the secure WebEx with QSEs to establish direct communication from 7:00 am - 1:00 pm
    • 7:00 am - 9:00 am: ERCOT and QSEs work to resolve any market submission issues and/or telemetry issues
    • 9:00 am - 1:00 pm: Coordination of real-time cutover and cutback

Lastly, a reminder that if the QSE has a Resource that cannot comply with RTC+B dispatch, the QSE can submit an exception request ahead of the LFC test to the ERCOT Control Room using the NDCRC application (more details on slide 13 from September 4 LFC Workshop #3).

ERCOT appreciates the continued support and details supporting this Market Notice will be posted as part of tomorrow's meeting (9/10 RTCB Market Trials Preparation for Production LFC Test Webex).

ACTION REQUIRED: QSE should send the required LFC support contact information to RTCB@ercot.com by September 10, 2025 at 3:00 pm.

CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at ClientServices@ercot.com.

If you are receiving email from a public ERCOT distribution list that you no longer wish to receive, please follow this link in order to unsubscribe from this list: http://lists.ercot.com.

dg