MIS LOG IN

NPRR486

Summary

Title: Calculation of Generation to be Dispatched
Next Group:
Next Step:
Status: Withdrawn

Action

Date Gov Body Action Taken Next Steps
12/13/2012 PRS Deferred/Tabled PRS for consideration.
11/15/2012 PRS Deferred/Tabled PRS for consideration.
10/18/2012 PRS Deferred/Tabled PRS for consideration.

Voting Record

Date Gov Body Motion Result
12/13/2012 PRS To table NPRR486. Passed
11/15/2012 PRS To table NPRR486 for one month. Passed
10/18/2012 PRS To to table NPRR486 and to refer the issue to WMS and ROS Passed

Vote tallies here reflect individual votes, not the weight of the votes by market segment. Affirmative votes are not recorded in these vote tallies. For additional details on the voting record, please consult the Recommendation or Action Report, or the official vote tally if available, as posted in the key documents.

Background

Status: Withdrawn
Date Posted: Oct 3, 2012
Sponsor: Luminant Energy Company LLC
Urgent: Pending
Sections: 6.5.7.3
Description: This Nodal Protocol Revision Request (NPRR) proposes revisions to specify the method for calculation of generation to be dispatched. This NPRR specifies that the generation to be dispatched input should be based on the sum of expected Updated Desired Base Points for all Generation Resources plus the amount of Regulation Service deployed at the time of the determination of GTBD for each execution of the Security-Constrained Economic Dispatch (SCED).
Reason: As a result of the analysis of actual amounts of Regulation Service deployed on an hourly basis since the Nodal market implementation, it has been noted that the quantities of Regulation Service energy deployed have generally increased over time due to the bias toward Regulation Up Service (Reg-Up) compared to Regulation Down Service (Reg-Down). Additionally, there have been many hours where Regulation Service in only one direction has been deployed for the entire hour. Paragraph (2) of Protocol Section 6.5.7.3 specifies: "the SCED solution must monitor cumulative deployment of Regulation Services and ensure that Regulation Services deployment is minimized over time." In addition, paragraph (4)(b) of Protocol Section 6.5.7.6.2.1, Deployment of Regulation Service, requires that "ERCOT shall minimize Reg-Up and Reg-Down energy as much as practicable in each SCED cycle." Changing the current calculation of the generation to be dispatched input from using the sum of actual generation to using the sum of desired generation (i.e., Updated Desired Base Point), plus the amount of Regulation Service, will better minimize actual Regulation Service deployed. Data reviewed in the Qualified Scheduling Entity (QSE) Managers Working Group (QMWG) indicates there are many Generation Resources that have small deviations between actual output and desired output that are too insignificant to cause those Resources to fail Generation Resource Energy Deployment Performance (GREDP) metrics or incur Base Point deviation penalties, but that in aggregate, cause significant deployments of Reg-Up. For example, if 200 Generation Resources are On-Line and deviate from their Base Points by only one MW each in the same direction, the amount of Regulation Service deployed is consistently biased to deploy an extra 200 MW.

Key Documents

Related Content