NOTICE
DATE: June 9,
2008
NOTICE
TYPE: M-A060608-02 PRR
CLASSIFICATION:
Public
SHORT
DESCRIPTION: Implementation of PRR764, Zonal
Congestion and CSCs/CREs
INTENDED
AUDIENCE: QSE Settlement and Operations
personnel
DAY
AFFECTED: Operating Day June 9,
2008
LONG
DESCRIPTION: Effective 0800 CPT Monday, June
9, 2008 ERCOT has implemented congestion-management operations under Protocol
Revision Request 764, “Zonal Congestion and CSCs/CREs.” This revision was
approved by the Electric Reliability Council of Texas (ERCOT) Board on Friday
June 06, 2008. Other aspects of
PRR764, such as the reevaluation of CREs, remain to be
implemented.
The operations
revision specified by PRR764 requires that CSCs/CREs will be managed using zonal
congestion management guidelines.
Specifically Zonal Balancing Energy can be deployed only for Congestion
Management purposes to resolve flow limit violations on CSCs and CREs where the
base case or post-contingency limiting element is the CSC or CRE, unless an
Emergency Condition is declared by ERCOT.
In addition,
ERCOT Operations will determine CSC Limits as follows:
(1)
Determine the pre-contingency flow limit
on the directional CSC that results in the CSC or any directional CRE
corresponding to the CSC becoming the base case limiting element, for all
Congestion Zone-to-Congestion Zone transfer studies.
(2)
Determine the pre-contingency flow limit
on the directional CSC to withstand any single contingency that results in any
directional CRE, including elements comprising the CSC, corresponding to the CSC
to become the post-contingency limiting element for all Congestion
Zone-to-Congestion Zone transfer studies.
(3)
The lower of the CSC flow limits from (1) and (2) above sets the CSC
Limit
The day ahead advisory
limits will be posted on the ERCOT website at https://tcr.ercot.com/default.cfm?func=tcrpostings .
Real-Time the limits will
be posted http://mospublic.ercot.com/ercot/jsp/csc_cre.jsp each hour.
ADDITIONAL
INFORMATION: The revision modifies protocols
and specifies the use of zonal congestion for CSC/CREs, allowing the grid
operator to resolve a particular type of transmission congestion with
local-congestion management techniques, rather than the zonal-congestion
management used currently. .
The protocol revision specifies the use of
CSC’s and CREs for the contingency element/limiting element pair in
establishing the CSC limits. ERCOT will use Zonal Balancing Energy to solve
these congestions issues and will use local congestion to solve all non- CSC/CRE related
congestion.
Under
local-congestion management, the grid operator is able to deploy “out-of-merit”
generation, as opposed to “merit order” which is based on bids stacked from
least to most expensive.
The details of PRR764 may
be found on the ERCOT website at:
http://www.ercot.com/mktrules/issues/prr/750-774/764/
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
e-mail at [log in to unmask].
If you are receiving e-mail
from an 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.
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