***** EXTERNAL email. Please be cautious and evaluate before you click on links, open attachments, or provide credentials. ***** NOTICE DATE: December 31, 2018 NOTICE TYPE: W-A123118-01 Operations SHORT DESCRIPTION: Change to maximum Shadow Prices for constraints previously determined as irresolvable by SCED INTENDED AUDIENCE: ERCOT Market Participants DAY AFFECTED: January 1, 2019 and January 30, 2019 LONG DESCRIPTION: Section 3.6.2 of the Other Binding Document, Methodology for Setting Maximum Shadow Prices for Network and Power Balance Constraints, requires ERCOT to review annually each constraint previously determined irresolvable by Security-Constrained Economic Dispatch (SCED) and determine (1) if the constraint has become SCED-resolvable, and if not, (2) re-determine the maximum Shadow Price. Effective January 1, 2019, the following changes will be made to the set of constraints that remain consistently irresolvable by SCED: Contingency Name Constraint Name From Station / kV Description Current Maximum Shadow Price ($/MWh) Maximum Shadow Price Effective 1/1/19 ($/MWh) BASE CASE VALIMP N/A Valley Import Base Case 2,000.00 2,000.00 SJUNYEL9 HEXT_YELWJC1_1 YELWJCKT / 69 Loss of Yellow Jacket to Junction 69KV line overloading the Yellow Jacket to Hext LCRA 69 kV line 2,000.00 2,000.00 SWINYUC8 M_69_F3_1 WICKETT / 69 Loss of the 138 kV line from Wink Sub to Yucca Drive Switch overloading the 69 kV line from Wickett TNP to Winkler County 6 TNP 2,000.00 2,800.00 DCASTXR8 MHONDOCR_1 MOORE / 138 Loss of the 138 kV double-circuit from Razorback/Txresrch to Castrvll overloading the 138 kV line from Moore Switching Station to Hondo Creek Switching Station 2549.21 3500 SWCSBOO8 BARL_FTSW1_1 FTSW / 69 Loss of the 138 kV line from Fort Stockton Plant to Barilla and Solstice overloading the 69 kV line from Barilla to Fort Stockton Switch 2,800.00 2,800.00 Additionally, effective January 30, 2019, the following constraints will no longer be considered irresolvable by SCED: Contingency Name Constraint Name From Station / kV Description SBAKHL48 6596__F HLTSW / 69 Loss of Bakke Tap to Unocal Parker Bakke 138 kV line overloading the 69 kV line from Emma Tap to Holt Switch SWCSBOO8 6332__A YUCSW / 138 Loss of Solstice to Fort Stockton Plant 138 kV line overloading the 138 kV line from Yucca Drive Switch to Gas Pad Section 3.6 of the Other Binding Document requires a 30-day notice before the Shadow Price caps for SCED-resolvable constraints are reset to their default values. Accordingly, the identified constraints will have their Shadow Price caps reset to their default Shadow Price cap values on January 30, 2019. Per Section 3.6.3 of the Other Binding Document, the net margin values for constraints that remain irresolvable by SCED will be reset to zero on January 1, 2019. ADDITIONAL INFORMATION: The Other Binding Document, Methodology for Setting Maximum Shadow Prices for Network and Power Balance Constraints, may be found on the Other Binding Documents List<http://www.ercot.com/mktrules/obd/obdlist> page of the ERCOT website. 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. mm