ERCOT Congestion Management Working Group Meeting Notes - 10/18/21

1.

Antitrust Admonition

2.

Agenda Review

3.

RUC for Congestion on 9/21/21

·      ERCOT presentation posted and given (RUC for Congestion 20210921).

·      There was a lengthy discussion about where the constraints were versus the location of units that were RUC’d.

·      ERCOT was also asked why they RUC’d units on this day: to address binding constraints or for voltage support. (i.e., are they RUC’ing for reliability or economics). They answered that there were violations that they were resolving. They were asked about the relationship between units around Houston and issue in west Texas, and whether resource-specific information can be revealed. ERCOT could not give this specific information, but there was an unresolved contingency in the Houston area due to lack of generation and reactive support, and restricted flow in the west Texas GTC due to outages. Houston generation was committed because the voltage issues were in the Houston area.

·      They were asked about the relationship between SCED and shadow prices. ERCOT didn’t have the specific information in front of them, but indicated that the RUC helped relieve these constraints. ECOT may do an analysis on this.

·      ERCOT will provide additional information next month based on this discussion.

4.

Improving the CRR Auction Models

·      A presentation was given on this last month, and the presenter followed-up on the discussion. The main issue is that short -term derates were being included in the long-term auctions.

·      Three options were proposed to address concerns that were raised and an SCR would likely be necessary:

1.             Including an estimated end date for NOMCR submission. TSP’s had some concerns about operational impact of this idea and the question was asked about what would happen if the derate lasted longer than expected and the TSP forgot to update the NOMCR. However, ERCOT initially thought that this option might be the most accurate because it would be specific to each outage. This could result in an incorrect line rating, but the operational impact would be mitigated if they system is set up not to trigger anything based on the end date provided. This issue could be addressed in the SCR.

2.             Requiring TSP’s to submit a corresponding NOMCR to bring the derated line back to its original/updated rating. It was pointed out that this could result in an incorrect line rating if the actual work completed differs from what was input.

3.             Include a flag that designates a line outage as temporary. TSP’s though it was interesting because they might be able to use this flag for other things. ERCOT thought this might result in a bigger window and result in incorrect inclusion of outages.

·      This discussion will continue next month and is also being discussed at NDSWG.

5.

RENA Update (Questions Only)

·      ERCOT presentation posted (Review of July RENA CMWG).

6.

Other Business

·      A question was asked about whether PST’s were being optimized in the CMWG auction model. ERCOT answered that these still are being optimized and will continue to be.

7.

Adjourn