Large Load Interconnection Process
Application-through-energization paths for hyperscale loads, including expedited tracks and BTM generation reforms.
Lessons
PJM Expedited Interconnection Track (EIT) — Order 2023 reforms
FERC Order 2023 (issued July 28, 2023) mandates serial-to-cluster interconnection-study reform at all FERC-jurisdictional RTOs (PJM, MISO, SPP, ISO-NE, NYISO, CAISO; ERCOT exempt as non-FERC-jurisdictional). Backdrop: PJM's queue holds >300 GW of pending generation (mid-2025); ~80% of legacy serial-queue projects withdrew before commercial operation. Cluster mechanics: 60-day scoping window, ERIS vs NRIS service types, DFAX-based cost allocation, Affected Systems Studies for cross-RTO impacts. PJM's Expedited Interconnection Track (EIT, 2024): fast lane for shovel-ready projects targeting 12-18 month studies vs 24-36 month standard cluster. Three gates — Feasibility → SIS → Facilities Study + ISA — with escalating milestone deposits forfeitable on withdrawal. Material modification (MW/technology/POI) kicks project out of EIT. Hyperscale relevance: load interconnection follows PJM Manual M-14H (separate from Order 2023), but most hyperscale projects accompany themselves with co-located/contracted generation that faces the cluster process — generation queue is now the gating factor for most PJM hyperscale energization timelines.
ERCOT Batch Zero — expedited large-load process
PUCT Substantive Rule §25.494 (adopted November 2024) defines the Large Load interconnection framework for ERCOT. Backdrop: >150 GW of pending Large Load Interconnection Applications (~2× total ERCOT peak of 85.5 GW). Threshold: Large Load = ≥75 MW at single POI. Batch Zero = first batch under the new rule (captures legacy backlog); 4-5 batches per calendar year thereafter. Sponsoring TDSP is the legal applicant on behalf of the end-use customer. Flow: LIA filed → Pre-screening → Impact Study → Facilities Study + Interconnection Agreement → construction → energization (~24-48 months total). 50% MW deposit required at Impact Study entry; withdrawal forfeits deposits unless force majeure. Material modification (MW/POI/load-type) triggers restudy (+6-12 mo). Hyperscale dimensions: co-location (Configuration A pure BTM, Configuration B separately metered), Emergency Response Service (ERS) load curtailment participation, compliance with IEEE 2800 / PRC-024 ride-through. FERC Order 2023 does NOT apply (ERCOT non-FERC-jurisdictional) — ERCOT runs its own queue process.
Large Load Interconnection Studies — LLIS / RTP / RPG end-to-end
Three-tier engineering-study sequence governs every large-load interconnection at PJM (Manual M-14H), MISO (BPM-015), ERCOT (§25.494), and CAISO. Tier 1 Feasibility (60-120 d, $50-200 K) — high-level yes/no + cost range. Tier 2 System Impact Study / SIS (6-12 mo, $0.5-2 M) — powerflow under multiple scenarios + N-1 contingencies, dynamic stability for 3φ-fault transients (PSS/E + IEEE Std 1110-2002 models), short-circuit (ASPEN/CAPE) vs breaker ratings, harmonic analysis to IEEE 519 (PSCAD/HARMFLO) when power-electronic loads present. Tier 3 Facilities Study (4-8 mo, $0.5-5 M) — final engineering + binding cost estimate + executed Interconnection Agreement. Cost allocation: direct assignment (100% applicant) vs network upgrade (DFAX) vs postage-stamp (rare). Affected Systems Studies coordinate cross-RTO impacts at major seams (PJM-MISO, MISO-SPP, SPP-WECC, CAISO-WECC); ERCOT exempt. FERC Order 1920 (2024) expands long-term transmission scenario planning. Compliance documents: ISA / LGIA / ERCOT IA + NERC TPL-001-5.1 (P0-P7 contingencies), PRC-024 (V/freq ride-through), PRC-025, IEEE 2800-2022 (IBR standard), MOD-026/027/032 (model data). Violation penalties up to $1 M / day. Total studies → executed agreement: 12-30 mo; construction adds 12-36 mo.
Behind-the-meter generation reforms — co-located gen + large load
The Talen-AWS Susquehanna deal is the most important precedent in U.S. BTM co-location law for hyperscale loads. AWS bought the Cumulus data center campus adjacent to Talen's 2.5 GW Susquehanna nuclear plant in March 2024, with a plan to route 960 MW directly to co-located data centers. Talen + PJM filed an amended ISA at FERC as docket EL-24-114 (May 2024) increasing co-located load from 300 to 480 MW initially. FERC REJECTED the amended ISA 3-2 on November 1, 2024 — concerns: cost shifts to non-participating ratepayers, capacity accreditation of BTM-served generation, contingency planning on generator trip. Christie + Phillips dissented. Three co-location models: (1) pure BTM, (2) hybrid (Talen-AWS proposal), (3) separately-metered with dedicated line. Technical core disputes: capacity accreditation (does BTM-served MW count?), cost shift (BTM avoids T&D charges socialized via tariffs). State action: Virginia SCC Order PUR-2024-00045 restricts Dominion-territory co-location >100 MW; Texas PUCT relatively open under §25.494; OH/IN inquiries pending. Hyperscale strategy: jurisdiction selection matters; tolling agreements / bilateral PPAs preferred over full gen ownership to reduce regulatory complexity. PJM December 2024 compliance filing proposed cost-shift testing + capacity-accreditation rules. Framework remains in flux.