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NPRR #548 · Revision Request

NPRR548  Remove NPRR153 Grey Boxes and Clarify Fixed Quantity Block Treatment in the DAM

Approved sponsor ERCOT posted 2013-06-21 ercot.com
ReasonThe ERCOT Board approved NPRR153 on 1/19/10, and on 11/13/12 assigned a priority of 2013 and rank of 790 for the associated project. Recently, at the 5/8/13 WMS meeting and 6/4/13 Qualified Scheduling Entity (QSE) Managers Working Group (QMWG) meeting, ERCOT discussed with Market Participants the potential market clearing price impacts of implementing NPRR153, namely that clearing prices could be artificially reduced. While currently the DAM has fixed quantity blocks for energy, because the Ancillary Services market is much smaller, the magnitude of the price difference between the marginal offer price and the clearing price could be large. This NPRR is a result of those discussions and will remove the NPRR153 grey boxes to eliminate the requirement and implementation. Further, ERCOT believes it would be beneficial to clarify the way that the DAM is designed to price and clear fixed quantity blocks. Due to the nature of the market design and mixed integer programming clearing process, fixed quantity block bids can clear at prices that exceed their bid price, and fixed quantity block offers can clear at prices that are below their offer price, when the blocks are marginal. Block offers and bids do not set the clearing price and are essentially price-takers once selected in the commitment phase of the DAM. Further, fixed quantity blocks may fail to clear when seemingly economic based on the final Settlement Point Price. The language introduced in Section 4.5.1 clarifies that, for certain products, the clearing prices are subject to these inconsistent pricing scenarios. The intent is to improve market education and minimize disputes based on this market design construct.
Created2013-07-18
Approved2013-11-19
Sections Affected
4.4.7.2.14.4.9.5.14.4.9.6.14.5.1
Summary
This Nodal Protocol Revision Request (NPRR) removes the grey boxes that are pending implementation of system changes associated with NPRR153, Generation Resource Fixed Quantity Block. Further, this NPRR provides clarification for how the Day-Ahead Market (DAM) currently considers blocked offers and bids for Ancillary Services.
Action Log 4 milestones
Amendments
DateBodyMotionResult
Jul 18 '13PRS To recommend approval of NPRR548 as revised by PRS and to request that WMS review NPRR548 and submit comments.Passed
Aug 22 '13PRS To endorse and forward the 7/18/13 PRS Report as amended by the 8/20/13 ERCOT comments and Impact Analysis for NPRR548 to TAC.Passed
Documents 9
NameTypePostedClassification
548NPRR-01 Remove NPRR153 Grey Boxes and Clarify Fixed Quantity doc Jun 21 '13 Revision Request
548NPRR-02 Impact Analysis 062113 doc Jul 18 '13 Staff Report
548NPRR-03 PRS Report 071813 doc Jul 19 '13 Committee Report
548NPRR-04 ERCOT Comments 073113 doc Aug 20 '13 Revision Request Comments
548NPRR-05 WMS Comments 081513 doc Aug 20 '13 Revision Request Comments
548NPRR-06 ERCOT Comments 082013 doc Aug 20 '13 Revision Request Comments
548NPRR-07 PRS Report 082213 doc Aug 26 '13 Committee Report
548NPRR-08 TAC Report 090513 doc Sep 5 '13 Committee Report
548NPRR-09 Board Report 111913 doc Nov 19 '13 Committee Report
Meetings That Took It Up 6
DateMeetingCommitteeStatus
Nov 19 '13 Board of Directors Meeting BOARD Concluded
Sep 5 '13 Technical Advisory Committee (TAC) Meeting TAC Concluded
Aug 22 '13 Protocol Revision Subcommittee (PRS) Meeting PRS Concluded
Aug 14 '13 Wholesale Market Subcommittee (WMS) Meeting WMS Concluded
Jul 31 '13 Joint Credit Working Group (CWG)/Market Credit Working Group (MCWG) Meeting CREDITWG Concluded
Jul 18 '13 Protocol Revision Subcommittee (PRS) Meeting PRS Concluded