Title West Zone SCE Performance Conditions
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Next Step
Status Approved on 05/22/2008


Date Gov Body Action Taken Next Steps
06/17/2008 BOARD Approved
06/05/2008 TAC Recommended for Approval Consideration by the ERCOT Board.
05/22/2008 PRS Approved

Voting Record

Date Gov Body Motion Result
06/17/2008 BOARD To approve PRR762 as recommended by TAC and directed ERCOT Staff to report its impacts to the ERCOT Board 60 days after the implementation of this provision. Passed
06/05/2008 TAC To recommend approval of PRR762 as recommended by PRS. Passed
05/22/2008 PRS To grant Urgent status to PRR762. The motion passed with three opposing votes from the MOU (2) and Consumer Market Segments and four abstentions from the IREP (2), MOU and IPM Market Segments.All Market Segments were present for the votes. Passed


Status: Approved
Date Posted: Apr 21, 2008
Sponsor: AEP
Urgent: Yes
Sections: 6.10.6, ancillary service deployment performance conditions
Description: The PRR revises Section 6.10.6 to exclude from consideration of performance periods where Qualified Scheduling Entities (QSEs) operating controllable units in the West zone are called upon to deploy and recall Balancing Energy in response to high wind production and Congestion in the area.
Reason: Due to the limited transmission capability in the West zone and the abundance of uncontrollable renewable Resources, often times even coal fired generation operates on (or above) the margin and is called upon to reduce output to relieve Congestion. These instructions to reduce generation are, at times, short lived and subsequently recalled. Due to the competing and conflicting incentives of the market deployment and Scheduling Control Error (SCE) performance requirements, coal fired units can offer only a portion of their ramping capability or risk SCE performance violations. This additional exception from the SCE performance calculation will allow QSEs representing such units to make available higher amounts of ramping capability to reflect their ability to ramp down to resolve Congestion more quickly, while at the same time recognize they can not recall (re-load) the unit at the same rate. Making such additional ramping capability available should reduce the curtailments (down balancing, OOME or otherwise) necessary from other lower cost, likely wind, Resources.

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