PRS unanimously voted to recommend approval of NPRR249 as revised by PRS
Jul 5, 2010
3.2.5, Publication of Resource and Load Information 6.4.5, Resource Status 188.8.131.52, Ancillary Service Qualification and Testing
This Nodal Protocol Revision Request (NPRR) removes the requirement for Qualified Scheduling Entities (QSEs) with Resources to submit a text reason to ERCOT when a Resource’s telemetered High Sustained Limit (HSL) or Low Sustained Limit (LSL) deviates from a normal high or low limit.
Protocol Section 6.4.5, as written, creates a degree of ambiguity as to the trigger when a QSE must submit a text reason for the modification of an HSL. The ambiguity stems from the phrase "normal limit" and to the reference of the Resource Parameter list in section 3.7.1, Resource Parameter Criteria. The only limits identified in Section 3.7.1 are the high reasonability limit and the low reasonability limit. These limits are considered guardrail limits to ensure that a QSE does not enter a HSL or LSL inadvertently in the Current Operating Plan (COP) that shows a capacity for the Resource significantly beyond the true capability of the Resource (i.e. if a QSE is entering a COP for a 100 MW Resource with a High Reasonability Limit (HRL) on 125, this will prohibit a data entry error of a 1000 MW HSL).
The issue that this Protocol requirement addressed is the ability to maintain a record of reasons why a Resource telemetered a capacity limit that was greater than a stated capacity for the Resource, but in Real-Time could not produce the energy up to the telemetered limit. On January 19, 2010, the ERCOT Board of Directors passed NPRR194, Synchronization of Zonal Unannounced Generation Capacity Testing Process, which replaced the seasonal testing requirement with unannounced testing. NPRR194 also required Resources to update their HSL seasonally. NPRR194 combined with paragraph (2) of Section 184.108.40.206, which states that a Resource may not submit an HSL above its stated Net Dependable Capability as set via general capacity tests, creates a Protocol violation for any Resource that overstates its capacity capability. This removes the need to maintain a text reason why a Resource telemeters an HSL above its Net Dependable Capability. Thus, this NPRR removes the need for QSEs to provide a text reason when the HSL or ramp rate is modified.