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Proposed Revision Request Detail Help
PRR Life Cycle*****Stakeholder Meeting on Recommendation****
PRR Details
PRR #
1663
Title Changes due to the day-ahead market enhancements and extended day-ahead market policy initiatives
Date Submitted 2/27/2026 5:07 PM
PRR Category C
Priority Normal
Owner Mohammed-Ali, Abdulrahman (CAISO)
Status Stakeholder Meeting on Recommendation
Status End Date 4/14/2026 11:59 PM
Related BPM Reliability Requirements
BPM Section 7
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Existing Language

​See attached redline BPM document.

Proposed Language

​See attached redline BPM document.​​

Reason For Revision

​BPM changes due to the new rules introduced by the Day-Ahead Market (DAME) and Extended Day-Ahead Market (EDAM) policy initiatives. 

Click here to view the Recommendation Details for this PRR
BPM PRR Submitter

Mohammed-Ali, Abdulrahman (CAISO)
Modified BPM language proposed by the PBM Chnage Management Coordinator

​See attached

Identification of the authorship of comments

Action

Approve the BPM PRR as submitted

Proceed with the original draft language as submitted.
Statement of apparent requirements of the BPM PRR

CAISO reply comments to initial comments are attached to PRR.
Priority and rank for any BPM PRR requiring a CAISO system change

Proposed effective date(s) of the BPM PRR

5/1/26
Other recommended actions

Announcements
Please note updated PRR attachment posted 3/3/26
Posted On - 3/3/2026 5:17 PM
Impact Analysis
PRR Impact Analysis Form 1663.doc    
Notes:
Initial Comments
PG&E’s comment: this section establishes an 8:00 AM Day Ahead Market reassignment deadline on the calendar day prior to the trading day.  PG&E notes that this 8:00 AM deadline is not specified in the tariff, so this can be altered if the BPM review process determines that it should. In PG&E’s view, an 8:00 AM deadline impacts dependencies outside of the ISO. Notably, the EDAM entities that are being reassigned to will require the source information before the 8:00 AM deadline. Given current trading and scheduling practices, confirming a source (EDAM or non-EDAM) before 8:00 AM is difficult and often not possible. This could result in an increase in unspecified schedules being submitted to the ISO. The ISO should clarify the intended purpose of the 8:00 AM deadline and consider whether an adjusted reassignment timeline is necessary in light of the intertie scheduling realities and third party SC approval requirements.
3/17/2026 4:27 PM
Logged By - Alan Meck (PG&E)
The Six Cities have the following questions concerning revisions included in the indicated sections for PRR 1663 - -
Re § 7.1.2(9) - - The Six Cities have been unable to locate any tariff section relating to the concept of overlapping RA capacity described in § 7.1.2(9), and the reference to a “true-up settlement” is unclear.  What would be “trued-up” in the situation of overlapping capacity.  The Six Cities request that the CAISO provide additional explanation regarding the purpose and mechanics for the described LSE-RA Resource True-up settlement, including an illustrative example.
Re § 7.4, next to last paragraph - - The language stating that “[t]he SC will be able to adjust or cancel reassignment for future TDs that have not had the DAM run for that TD” appears to conflict with the requirement that reassignments be submitted and approved by 8:00 a.m. on the calendar day before the trading day.  The Six Cities request that the CAISO clarify the timing for submission of an adjustment to or cancellation of a reassignment.
3/17/2026 2:32 PM
Logged By - Bonnie Blair (Cities of Anaheim, Azusa, Banning, Colton, Pasadena, and Riverside, CA)
SCE Comments for PRR1663.pdf    
Please see Southern California Edison's comments.
3/17/2026 2:10 PM
Logged By - John Diep (Southern California Edison)
Recommendation Comments
CAISO EDAM - DAME Implementation PRR 1663 Reliability Requirements - Vistra.pdf    
We have received written comments from Cathleen Colbert on behalf of Vistra on 4/14/26. Please see attached.
4/15/2026 9:03 AM
Logged By - Madrigal, Radha (CAISO)
TerraGen-Recommendation-Comments-PRR-1663.docx    
We have received written comments from Jake McDermott on behalf of Terra-Gen on 4/7/26. Please see attached. In addition, the following notes were provided for context: There are redlines in the attached doc on page 89 relevant to the NGR (Non-REM) for the summary of bidding requirements for resources providing RA capacity. (See Sec 7.1.1.). Terra-Gen recommends these redlines as needed changes to PRR 1663 to account for the fuel-limited nature of hybrid resources participating as NGRs. Without those redlines, the CAISO would assume that resources are required to submit RUC/RCU/RCD bids during all hours of the day which may not be possible for hybrids overnight.
4/7/2026 11:39 AM
Logged By - Madrigal, Radha (CAISO)
Attachments