***** EXTERNAL email. Please be cautious and evaluate before you click on links, open attachments, or provide credentials. ***** NOTICE DATE: December 10, 2019 NOTICE TYPE: M-A102419-03 Settlements SHORT DESCRIPTION: ERCOT Board approval of Real-Time market (RTM) price corrections for Operating Days (ODs) October 16 - 20, 23 24, 26, 29 31, 2019, and November 4 & 6, 2019 INTENDED AUDIENCE: QSE and CRRAH Settlement Personnel DAYS AFFECTED: October 16 - 20, 23 24, 26, 29 31, 2019, and November 4 & 6, 2019 LONG DESCRIPTION: On October 21, 2019, ERCOT became aware of a software error that occurred during an update to ERCOTs Energy and Market Management System (EMMS), and immediately implemented an emergency fix and began investigating RTM prices for Operating Days (ODs) October 16 21, 2019. ERCOT determined that the software error resulted in incorrect Real-Time Locational Marginal Prices (RTLMPs), Real-Time Settlement Point Prices (RTSPPs), Real-Time Settlement Point Prices for Energy-Weighted (RTSPPEWs), and Real-Time Prices for Energy Metered for Resources (RTRMPRs) for certain intervals on ODs October 16 21, 2019. On October 24, 2019, ERCOT notified Market Participants that it would be seeking ERCOT Board review of such prices. See Market Notice M-A102419-01. On November 14, 2019, ERCOT issued a second notice informing the market that ERCOT identified a separate but related software error that impacted ODs October 16, 2019 November 7, 2019. ERCOT informed Market Participants that there were no pricing impacts to the ODs affected by the original software error (i.e., ODs October 16 21, 2019). ERCOT further noted that there were no pricing impacts to ODs October 22, 25, 27 28, 2019, November 1 3, 5 or 7, 2019, as a result of the separate but related software error. However, for ODs October 23 24, 26, 29 31, 2019, and November 4 and 6, 2019, ERCOT determined that the second software error impacted prices, and therefore, ERCOT stated that it would be recommending these additional ODs to the Board for review of prices. See Market Notice M-A102419-02. On December 10, 2019, the ERCOT Board reviewed RTLMPs, RTSPPs, RTRMPRs, and RTSPPEWs for ODs October 16 20, 23 24, 26, 29 31, 2019, and November 4 & 6, 2019, determined that such prices were significantly affected by a software error, and directed ERCOT to implement the appropriate price corrections pursuant to ERCOT Protocol Section 6.3(4). See ERCOT Board of Directors Meeting (December 10, 2019) Agenda Item No. 9.<http://www.ercot.com/calendar/2019/12/10/161482-BOARD> In accordance with the RTM Settlement posting dates per the Settlement Calendar<http://www.ercot.com/mktinfo/settlements>, ERCOT will include the price corrections in the RTM Final Statements for ODs October 16 20, 23 24, 26, 29 31, 2019, and November 4 & 6, 2019. ADDITIONAL INFORMATION: The corrected prices will be posted in both CSV and XML formats in the RTM Price Corrections<http://www.ercot.com/mktinfo/prices/> folder. 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 [log in to unmask]<mailto:[log in to unmask]>. 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<http://lists.ercot.com/>. mm