PJM IMM Doubles Down on Sampling Safeguards, Adds CBL-Based Performance Metric Demand in Second Round of FERC Briefing

The PJM IMM filed a November 4, 2026 Answer in FERC Docket No. EL26-4 responding to a October 22, 2026 Answer from Voltus/Mission:data that had opposed the IMM's October 14 Reply Brief safeguards. The new IMM filing enumerates its full list of 11 required conditions for any statistical sampling approval (including a specific 100 UCAP MW initial cap, a pre-implementation pilot test, PJM's 5%/95% standard, and ongoing validation/audit authority), and adds new substantive demands: replacing PJM's PLC-based performance metric with a CBL-based incremental-reduction metric, strengthening nonperformance penalties specifically for sampling-based resources, ending cross-footprint CSP netting that masks local underperformance, and rejecting manipulation-risk dismissals tied to CSP-customer interaction asymmetries. The IMM also rebuts Voltus's framing of sampling as a 'temporary bridge' pending ComEd's 2028-2029 automated data-sharing initiatives, flags Voltus's stated intent to sell sampling-based residential capacity to data centers as inappropriate risk-shifting, and asks the Commission to order PJM, Voltus, and the IMM to jointly develop detailed screening and statistical-method criteria.

The dispute has expanded beyond whether and how much statistical sampling to allow into a parallel fight over how demand response performance itself is measured and penalized, meaning any FERC-approved framework will likely need to resolve both the sampling-eligibility question and a redefinition of the performance baseline (CBL vs. PLC) used for settlement. This widens the scope of the eventual order and raises the stakes for CSP revenue models, since a shift to CBL-based measurement and stricter, sampling-specific penalties would materially change compensation and liability exposure for underperforming demand resources, while the data-center angle highlights how sophisticated commercial counterparties could exploit a residential-targeted accommodation.

This second round of adversarial briefing signals the record is becoming more contested rather than converging, which typically precedes either a narrower, more conditional Commission approval or a request for further technical conference/compliance filing rather than a clean up-or-down ruling. The IMM's explicit ask for a Commission-ordered collaborative process to jointly develop screening criteria and statistical methods suggests the IMM itself anticipates that FERC may not resolve implementation details in its initial order, implying a likely multi-phase rulemaking-style sequence (threshold approval, then detailed compliance filing) rather than immediate go-live of any sampling methodology. The CBL/PLC performance-metric fight, if adopted by FERC even for metered resources' sampling-adjacent treatment, could become a template dispute point for other RTOs' demand response accreditation rules.

FERC Federal Power Act proceeding, Docket No. EL26-4; PJM Open Access Transmission Tariff (OATT) Attachment K Appendix, Operating Agreement, Reliability Assurance Agreement, and PJM Manuals 11 and 19

FERC Commission order resolving the paper hearing in Docket No. EL26-4

Primary sources