WECC Path Rating Process

December 3, 2020

Peter Mackin, GridBright, Inc.

StS Chair

WECC Path Rating Process

Overview

 Project Coordination Process –

• Facilitates informing others of the opportunity to participate in or review a project and solicits participation

• intends to:

o Avoid duplication of projects

o Allow a new project to integrate the needs of other WECC member(s) by mutual agreement.

 Path Rating Process (also known as the 3-Phase Rating Process) –

• Provides new projects being integrated into the system with a Path rating, while recognizing protected ratings of other Paths.

 Progress Reports Policies and Procedures –

• Requires reports from project sponsors regarding potential significant additions and

changes to the Western Interconnection. WECC members are provided the opportunity to review and comment on these additions or changes.

Definition of Significant

 A significant transmission project is defined as 200 kV and above

(for transformer banks the operating voltage refers to the low side

of the transformer bank) unless granted a waiver by the Reliability

Assessment Committee (RAC) chair based on the two criteria

below and in accordance with the process outlined in Subsection 4

of the Project Coordination Process:

1. The purpose of the transmission project is to serve local load.

2. The transmission project does not have a significant impact on the operation of the Western Interconnection.

Timeline of Project Coordination and

Path Rating Processes

Notes:

 “Proposed Rating” – used at the initiation and throughout Phase 1 of the Path Rating Process.

 “Planned Rating” – final rating at the conclusion of Phase 1 of the Path Rating Process and used throughout Phase 2 of the Path Rating Process. Phase 2 consists of Phase 2A and Phase 2B. Completion of Phase 2 requires completion of both Phases 2A and 2B. Please refer to Section 5 of the Path Rating Process for more detailed description of Phases 2A and 2B.

 “Accepted Rating” – final rating granted at the conclusion of Phase 2 of the Path Rating Process and is also the rating that is used when the Project is placed in-service.

Project Coordination Process

(Phase 0)

Project Coordination Process

 Occurs independently and in parallel with Phase 1 of the Path Rating Process

 Must be completed prior to entering Phase 2

 Can be:

• Requested by RAC, or

• Project sponsor, or

• Affected member

 Project Sponsors form Project Coordination Review Group (PCRG) –

• will prepare a Project Coordination Report indicating how the project conforms or plans to conform to each of the 4 Project Coordination Review Objectives:

1. Undertake Integrated Project Evaluation

2. Conduct Coordination and Outreach

3. Describe Generation Resources and Related Policy Initiatives

4. Consider Reasonable Alternatives to the Project

Completing the Project Coordination

Process

 Project Sponsor writes a Project Coordination Report and submit to RAC

 Report to be posted for 30-day review and comment on the project’s conformity with the Project Coordination Review Objectives.

 WECC staff notifies all WECC members of the posting.

 Project Sponsor addresses comments from this review

 Project Sponsor will notify the RAC chair.

 The RAC chair will notify the Project Sponsor as well as the RAC and Studies Subcommittee (StS) of the completion of the Project Coordination Process.

 If a project sponsor does not demonstrate any evidence of activity for 18 months, the project will no longer be considered to be within the Project Coordination Process.

Progress Report Policy and Procedures

Progress Report Process

 Applicable to:

• Generators ≥ 200 MW

• New & upgraded transmission > 200 kV

• Other with significant impact to reliability

• Can include new, re-designs, upgrades, removals, loop-in, operating procedure changes, etc.

Unless a waiver is granted

Progress Report Process

Project Sponsors send Report(s) to StS and WECC Staff:

• Initial Progress Report

• Soon after project is made public

• Comprehensive Progress Report

• Soon enough to allow changes from member review & input

• Requirements 1-5 for all projects subject to this procedure

• Additional Requirements 6-11 for Projects intending to go through the Path Rating Process

• Supplemental Progress Reports – annually

• For Projects with no significant changes in Plan of Service, capacity, or in-service dates since the Comprehensive Progress Report was filed.

• Non-significant additions or revisions to the projects.

• Review of Progress Reports & Projects

• Presentations at StS meetings

Path Rating Process

Timeline of Project Coordination and

Path Rating Processes

Notes:

 “Proposed Rating” – used at the initiation and throughout Phase 1 of the Path Rating Process.

 “Planned Rating” – final rating at the conclusion of Phase 1 of the Path Rating Process and used throughout Phase 2 of the Path Rating Process. Phase 2 consists of Phase 2A and Phase 2B. Completion of Phase 2 requires completion of both Phases 2A and 2B. Please refer to Section 5 of the Path Rating Process for more detailed description of Phases 2A and 2B.

 “Accepted Rating” – final rating granted at the conclusion of Phase 2 of the Path Rating Process and is also the rating that is used when the Project is placed in-service.

Path Rating Process

Paths Subject To This Procedure

 The limiting condition (e.g., thermal limit, stability, or voltage) in determining the Total

Transfer Capability of the path or the System Operating Limit for transmission facilities that impact the path is on another system and the affected member system requests the path be rated.

 The path must be operated within the constraints of a nomogram to meet NERC Reliability Standards and WECC Criteria, the elements of the nomogram (e.g., path flows or generation levels) are in different systems, and one of those systems or a neighboring member system requests the path be rated.

 The path owners or operators have requested a seasonal or operational Total Transfer Capability for a new path or the path owners or operators have requested a seasonal or

operational Total Transfer Capability that is in excess of an existing path’s rating (Accepted, Existing, or Other).

 A facility (generator, series, or shunt reactive equipment; Remedial Action Scheme; etc.) that an Existing or Accepted Rating depends on is modified¹⁰ or retired from service, without regard to whether the facility is owned by the same system as the rated path.

10 If the modified RAS is functionally equivalent to the existing RAS and is approved by the RASRS, then the Path does

Loss of Rating Status – Phase 2

The start time is initiated once a Project enters Phase 2A. The following requirements shall be met or the

Project in Phase 2 will either revert back to Phase 1 or Phase 2A (depending on if the Project is in Phase 2A or 2B) under the following conditions:

Elapse time (calendar days)

without activities*

Project reverts back to If project sponsor does not form a Project Review

Group while in Phase 2A

StS

chair/StS 60 days Phase 1

If project sponsor does not initiate any study on

simultaneous Path Transfer Capability limits PRG 12 months¹⁶ Phase 1 If project sponsor misses completing any Project study

milestones by 12 months or more PRG 12 months¹⁷ Phase 2A

If project sponsor does not show any evidence of any activity for 12 months during Phase 2.

StS

chair/StS 12 months Phase 1 If the project sponsor cannot be located by the StS

chair or WECC staff, or no response is received from the project sponsor after a formal WECC

announcement on the Project status has been made.

StS

chair/StS 18 months Remove the project from the WECC

Log

Recent Changes to the PRP

 Process to Re-rate an existing Path Rating limited by Common Corridor Outages

 The following steps will be used as the process to rerate a path.

 This process would also be applicable to future criteria changes, if any.

Step1

•Notification asking if the Owners of existing Paths limited by common corridor outages wish to re-rate their Paths

Step 2

•Notifications announcing which Paths are requesting rerating

Step³

•Path Owners perform studies and prepare

Comprehensiv e Progress Reports (CPR) with proposed Planned (new) Ratings

Step 4

•Notification with CPRs to WECC

members

Step 5

•Path re-rating request

withdrawal

Step 6

•A revised list of Paths that still wish to proceed with the re-rating process

Step 7

•Path Owners that remain in the path re- rating study process form PRGs if there is interests in their re-rating process

Step 8

•Path Owners and PRGs follow the normal path rating process to complete Phases 2A, 2B and 3

Recent Changes to the PRP

 Changes necessary to align the Path Rating Process with the

current criteria.

 Clarifying the terms Regional and Sub-regional Planning Groups

and Project Sponsor.

 Requirements/ responsibility of a Path owner in the event of

resource retirement if the Path Rating is dependent on that specific

resource.

 Examples of different Path Rating scenarios have been updated

based on the updates to the PRP.

Contact:

Peter Mackin

StS Chair

[email protected]

Backup Slides

Path Rating Review Process

• Objectives

• Integrate projects while preserving reliability and efficiency

• Communicate plans, performance & limitations

• Discover simultaneous limitations & resolve

• Participation in review of project studies

• Conclude studies in a timely manner

• Facilitate development of curtailment sharing agreements

• Result: Determine mitigation and by whom

Phase 1 - Path Rating Review Process (1)

• Begins with Announcement

• Significant Additions Report, or

• Letter of Notification to StS, Staff & RAC, or

• Initial Progress Report

• ** Proposed Rating **

Phase 1 - Path Rating Review Process (2)

• Completed when:

• Project Coordination Report complete, accepted by RAC

• Modeling given to Staff for WECC base cases

• Comprehensive Progress Report

o Given to StS, Staff & RAC

o Minimum 60 day review after received by Staff

o Staff record of Member comments are resolved, or

o Project Sponsor can agree to resolve outstanding issues in Phase 2

Phase 1 - Path Rating Review Process (3)

• StS Chair notifies RAC and StS

• Acceptance of Comprehensive Progress Report (not approval)

• Checks with Staff on comments and resolution

• 60 day Comprehensive Progress Report period may overlap Phase

2 in Expedited Process - discussed later

Phase 2 - Path Rating Review Process (1)

** Planned Rating **

• Considered on equal basis where similarly situated in Phase 2 (See

Appendix B):

• Phase 2A = Projects completed Phase 1

• Phase 2B = Phase 2 Projects that have completed and obtained approval by the

PRG of a study plan and the first base case (or Foundational Base Case) needed to perform simultaneous studies.

• Project sponsor send letter to Staff, StS, RAC, and OC requesting interest

in participating in a Review Group

• Members have 30 days from date letter is received by Staff to respond with interest

Phase 2 - Path Rating Review Process (2)

• Project Review Group (PRG) purpose

• Demonstrate meets Planning Standards

• Identify non- and simultaneous path limits

• Address mitigation of simultaneous limits

• Resolve comments on Comprehensive Progress Report

Phase 2 - Path Rating Review Process (3)

• Completed when

• Project Sponsor issues Phase 2 Rating Report

• 60 day Review Group review after Staff distributes

• Staff record of Review Group comments are resolved

• RAC Chair notifies RAC, StS, and OC

• Acceptance of Phase 2 Rating Report (not approval)

• Checks with Staff on comments and resolution

• Project has entered Phase 3

Phase 3 - Path Rating Review Process

** Accepted Rating **

• Monitoring Project Progress, at risk if:

• Fails to complete plan of service

• Failure of other projects required for rating

• Failure to follow schedule (> 12 month delay)

• Completed when

• Construction is complete

• Operating procedures are accepted

• Placed in operation

Expedited Process

• Phase 1 review of Comprehensive Progress Report (60 days) -

OVERLAYS - Phase 2 invitation for Review Group (30 days) and

Phase 2 Rating Report

• Project Sponsor

• Declares intention to follow Expedited Process, and sends

o Letter of Notification

o Comprehensive Progress Report

o Requests interest for Review Group

Expedited Process

• Members have 60 days to review Comprehensive Progress Report

• Members must state their interest in a Review Group in 1st 30 days

• Project Sponsor include OPS and TOS if upgrade is within 6

months

• Project stays in Phase 1 until completion of Expedited Process

Loss of Rating Status – Phase 3

Phase 3 Accepted Rating Status may be lost if:

• a delay in meeting any Project milestones by 12 months or more

occurs, or,

• a change in the Project's Plan of Service adversely impacts the

Accepted Rating.

The PRG and the StS have the responsibility of monitoring the

progress of the Project in this Phase.