The current Capacity Critical Hours (CCH) methodology identifies a single set of CCH applicable across the entire WRAP Region. This methodology was developed more than five years ago based on the anticipated WRAP footprint and an expectation of a relatively interconnected regional system.
As the WRAP footprint and associated modeling have developed, a single regional set of CCH has become less representative of the conditions under which capacity is needed and available within the Program. The WRAP footprint has meaningful transmission constraints between areas, and other WRAP reliability modeling generally recognizes these limitations through the use of Subregions. The Program therefore does not assume that capacity available in one part of the footprint will necessarily be available to address a capacity need in all other parts of the footprint.
The proposed change would determine CCH separately for each WRAP Subregion. Load and applicable resource output would be aggregated at the Subregional level, and each Subregion would have its own set of CCH reflecting the periods of highest capacity need within that Subregion. This would better align the CCH methodology with the geographic framework used in other WRAP reliability modeling and with the transfer capability assumed between areas of the footprint.
The proposal would also replace the existing prescriptive Regional Interchange adjustment with a more general Additional Adjustments component. Additional adjustments could include regional interchange, impact of scarcity as determined by price, or other factors that materially 3 affect the determination of CCH. This would allow the methodology to account for relevant system conditions without relying on an interchange methodology developed for an earlier configuration of the WRAP footprint. The BPM language provides for documenting the assumptions used in the Additional Adjustments section and publishing that with the CCH dataset.
Any WRAP metrics and qualifying capacity contributions calculated after the effective date of this proposal will use the methodology provided here.
1Please supply any comments related to the proposed changes in BPM 104 - Capacity Critical Hours2Please supply any comments related to the proposed changes in BPM 108 - Forward Showing Submittal Process3Please supply any comments related to the proposed changes in the WRAP Tariff4General Comment
Comment Topic
Overview
Lead Sponsor's (WPP) Description of the Issue:
The current Capacity Critical Hours (CCH) methodology identifies a single set of CCH applicable across the entire WRAP Region. This methodology was developed more than five years ago based on the anticipated WRAP footprint and an expectation of a relatively interconnected regional system.
As the WRAP footprint and associated modeling have developed, a single regional set of CCH has become less representative of the conditions under which capacity is needed and available within the Program. The WRAP footprint has meaningful transmission constraints between areas, and other WRAP reliability modeling generally recognizes these limitations through the use of Subregions. The Program therefore does not assume that capacity available in one part of the footprint will necessarily be available to address a capacity need in all other parts of the footprint.
The proposed change would determine CCH separately for each WRAP Subregion. Load and applicable resource output would be aggregated at the Subregional level, and each Subregion would have its own set of CCH reflecting the periods of highest capacity need within that Subregion. This would better align the CCH methodology with the geographic framework used in other WRAP reliability modeling and with the transfer capability assumed between areas of the footprint.
The proposal would also replace the existing prescriptive Regional Interchange adjustment with a more general Additional Adjustments component. Additional adjustments could include regional interchange, impact of scarcity as determined by price, or other factors that materially 3 affect the determination of CCH. This would allow the methodology to account for relevant system conditions without relying on an interchange methodology developed for an earlier configuration of the WRAP footprint. The BPM language provides for documenting the assumptions used in the Additional Adjustments section and publishing that with the CCH dataset.
Any WRAP metrics and qualifying capacity contributions calculated after the effective date of this proposal will use the methodology provided here.
Response Guide
Prompts
Responses
Comments Received