The PJM Interconnection Planning Stakeholder (IPS) meeting on November 24 focused on multiple near-term operational issues and long-term planning changes shaping the 2026 Regional Transmission Expansion Plan (RTEP). The agenda included winter readiness, generator performance, modeling refinements, queue coordination challenges, long-term scenario development, and updates on affected-system study reforms. IPS continues to be PJM’s most technical planning forum, where TOs, developers, and PJM’s planning teams align on the assumptions and models underpinning the region’s reliability standards. Below is an expanded summary of all major takeaways.
Winter Readiness & Generator Performance Review
PJM provided a detailed update on expected winter conditions, emphasizing the divergence between average-weather forecasts and high-impact winter scenarios that have become increasingly common. Key points included:
- Updated Winter Peak Forecast: PJM highlighted elevated peak-load uncertainty driven by data center expansion in Virginia, Maryland, New Jersey, Pennsylvania, and Ohio. Many campuses are pursuing multi-phase growth plans, significantly affecting winter peaks because most of these facilities operate at constant loads even in cold weather.
- Cold Weather Generator Performance: PJM walked through historical performance data from the 2014 Polar Vortex, 2018 cold snap, December 2022 Winter Storm Elliott, and multiple smaller-scale winter events. Forced outages, cold-weather derates, and frozen instrument lines remain persistent risks among gas-fired units.
- Gas-Electric Coordination Challenges: PJM discussed its winter coordination efforts with regional pipelines and balancing authorities, highlighting nomination timing misalignment, insufficient firm transport contracts, and pipeline constraints near key load pockets.
Stakeholders noted that planning assumptions must incorporate realistic generator availability during extreme winter cold rather than the “idealized” average seasonal performance long used in steady-state analyses.
Planning Model Updates & Study Assumptions
IPS then transitioned to the heart of long-term planning: model development and the assumptions fed into thermal, voltage, short-circuit, and stability analyses. Key Modeling refinements reviewed:
- Load Model Enhancements: The load model now includes finer granularity at the EDC level, with improved modifiers representing data centers, electrification, hydrogen/hybrid facilities, and behind-the-meter resources.
- Generation Dispatch Scenarios: PJM detailed dispatch-case updates for high-renewable penetration, storage-dominated scenarios, and high-thermal-retirement cases. These outputs will directly influence the 2026 RTEP.
- Queue-Based Resource Modeling: IPS reviewed criteria determining which queue projects appear in the planning models. The new model distinguishes between early-stage queue resources with speculative COD dates and advanced-stage projects with PPAs, financing progress, or construction activity.
- Short-Circuit and Stability Model Clean-Up: PJM flagged material inconsistencies in short-circuit contributions for inverter-based resources and inaccuracies in dynamic models submitted during 2024–2025. A supplemental “model validation package” is forthcoming.
These modeling refinements have ripple effects for both TOs and developers, influencing congestion forecasts, needed transmission upgrades, and the likelihood of cost allocation changes affecting developers.
Long-Term Transmission Planning (LTRTP) & Scenario Development
PJM provided an update on long-term planning progress, tied closely to anticipated FERC Order 1920 compliance. Key topics included:
- Resource Shift Trends: Renewables and storage are rapidly displacing aging thermal units, altering system flows and requiring new transmission to maintain east–west and north–south reliability margins.
- Multi-Driver Project Evaluation: PJM reviewed candidate multi-value transmission projects intended to alleviate both reliability and market-efficiency constraints.
- 2035 & 2040 Scenarios: PJM walked through electrification assumptions (heat pumps, EVs, building electrification), offshore wind additions, solar clusters, and regional policy drivers.
Stakeholders stressed the importance of transparent modeling methodologies, as many members remain concerned that long-term assumptions could drive unnecessary or premature transmission expansion.
Queue Reform, Affected-System Processes & Interregional Dependencies
As always, IPS spent considerable time addressing persistent queue issues across PJM’s vast footprint. Key updates included:
- Affected-System Coordination: PJM provided updates on study coordination with MISO, NYISO, and TVA. Increased cross-border impacts from storage and hybrid projects continue to delay some clusters.
- Stability Study Backlogs: Inverter-based resources continue to require repeated model corrections, extending review cycles. Many projects remain held up due to missing EMT models or poorly aligned PSSE files.
- Queue Transparency Requests: Stakeholders asked PJM for visibility into when queue projects may be excluded from models due to incomplete data or low commercial viability.
TOs also requested consistent modeling standards for hybrid solar + storage facilities, specifically regarding control-mode interactions during disturbances.
Next Steps
PJM will publish updated model assumptions in December, with IPS reconvening in early 2026 to support the first phase of RTEP thermal and voltage screening.
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