ISO-NE Interconnection Process — Step by Step
1
Application
Submitted via ISO-NE's Generation Interconnection Request portal. Non-refundable fee: $10,000 (large gen >5MW). Queue position by application date. Requires site control attestation and detailed electrical data.
LGIP Section 3.1
2
System Impact Study (SIS)
Required for all projects. Full power-flow, voltage, and stability analysis. 6-month window typical. Fee: $350,000 (large gen). Identifies Network Upgrades and cost estimates. Results posted publicly on ISO-NE website.
LGIP Section 6
3
Facilities Study (FS)
Detailed engineering following SIS. TO designs direct-assigned facilities — gen lead, protection, metering. 6-month window. Cost: $125,000 + TO reimbursement for engineering time.
LGIP Section 7
4
Interconnection Agreement (IA)
30-day window after Facilities Study. Developer posts Interconnection Financial Assurance (IFA): $70/kW (wind/solar), $50/kW (storage). FERC GIA filing. ISO-NE board approval required.
LGIP Section 8
5
Capacity Interconnection Rights (CIRs)
Projects electing FCM participation acquire CIRs equal to qualified capacity. CIRs forfeited if commercial operation not achieved within 4 years of CIR acquisition. Key milestone for FCM financing.
LGIP Section 9 / FCM Rules
6
Commercial Operation
ISO-NE Synchronization Study. Protection settings validated. Revenue metering sealed. NERC/NPCC reliability standards verified. Project enters real-time market. CIRs activated (if FCM participant).
LGIP Section 11
Forward Capacity Market (FCM)
FCM Overview
What is the FCM?
ISO-NE's annual capacity auction procures resources 3 years ahead of the delivery year. Generators, demand response, and imports compete. New capacity receives 7.5-year price floor via Competitive Capacity Contracts (CCCs). Key for project financing — provides bankable forward revenue.
ISO-NE Tariff, Schedule 17
Participation
Qualification Requirements
New projects must pass a "show of status" to participate in FCM: site control, permits, executed IA or demonstrated progress. Projects that fail to deliver forfeit their Capacity Supply Obligation (CSO) plus a penalty payment proportional to shortfall.
ISO-NE FCM Qualification Rules
Import Limits
External Capacity Cap
ISO-NE limits external capacity import credits. Quebec (Hydro-Quebec) has historically provided 1,000–1,200 MW in FCM. New offshore wind imports from Quebec and Labrador may challenge existing import cap rules — FERC review ongoing.
ISO-NE Tariff, Schedule 17 §4.7
Recent Auction
FCA 20 — 2026 Delivery Year
Forward Capacity Auction #20 clears capacity for the 2026–2027 delivery year. Results show ISO-NE tightening — clearing prices rose sharply as coal/oil retirements accelerated. New entry price approximately $3.89/kW-month in most zones, higher in CT and NEMA.
ISO-NE FCA 20 Results (2023)
FERC & New England State Policy
Federal
FERC Order 2023 Compliance
ISO-NE filed compliance tariff January 2024. New cluster-based interconnection procedures with readiness milestones: M1 (site control), M2 (permit filing), M3 (permit received), M4 (IFA increase), M5 (COD). First cluster study launch: Q1 2025.
FERC Docket No. RM22-14
Connecticut
Millstone ZEC Program
Connecticut's Zero Emission Certificate program supports Millstone Nuclear (2,098 MW) through 2029. Without ZECs, Millstone retirement would create a massive capacity shortfall in ISO-NE. ISO-NE reliability is critically dependent on this single facility remaining operational.
CT Public Act 17-3
Maine
100% Renewable by 2040
Maine's ambitious RPS drives offshore wind + onshore wind queue development. A land-based wind development moratorium (repealed 2021) had chilled development. Maine is now actively permitting and has strong Gulf of Maine floating offshore wind potential (50+ GW resource).
Maine PL 2019 c.477
Massachusetts
83D Offshore Wind Mandate
Massachusetts Law Chapter 83D mandates 5,600 MW offshore wind procurement by 2030. Vineyard Wind (800 MW), Revolution Wind (704 MW), and New England Wind (1,200 MW) are all in the ISO-NE queue. This is the primary driver of interconnection cost escalation in RI and SEMA zones.
MA Acts 2021 c.8 §83D
Regulatory Timeline
2018
Vineyard Wind Selected
First US offshore wind project with a signed PPA in New England. ISO-NE interconnection studies begin. First large-scale OSW cost data point for the region.
2020
First ISO-NE Cluster Study
ISO-NE completed first cluster interconnection study under prior rules — 35 projects, mixed results. Offshore wind projects expose gaps in the existing study framework.
January 2022
ISO-NE Tariff Update
FERC-approved tariff update expanded SIS scope for offshore wind projects. New requirements for submarine cable routing studies and coastal interconnection substation design.
2023
Vineyard Wind Cable Landfall
Vineyard Wind Cable 1 reaches Barnstable, MA. Revolution Wind begins offshore construction. ISO-NE studies impacts on Canal substation 345kV headroom.
January 2024
FERC Order 2023 Compliance Filed
ISO-NE filed compliance tariff with new cluster procedures and readiness milestones (M1–M5). Effective for all new queue applications after February 2025.
Q1 2025
First Cluster Under New Rules
First ISO-NE interconnection cluster study launches under new FERC Order 2023 procedures. Includes offshore wind, solar+storage, and onshore wind projects.
2026
Vineyard Wind Phase 1 COD
Vineyard Wind Phase 1 (800 MW) expected commercial operation — first major offshore wind in New England. Establishes cost precedent for grid reinforcement amortization.
2027
Revolution Wind + Sunrise Wind
Revolution Wind (704 MW) and Sunrise Wind (924 MW) expected completion. Transforms RI and SEMA zones from pure importers to net-balanced or exporting zones at certain hours.