FERC Orders ISO-NE to Justify Large Load Transmission Tariff Terms
ISO-NE, its participating transmission owners, and New England large load customers must respond to FERC’s show cause order, which could overhaul regional transmission interconnection, cost allocation, and service rules for large energy users.
On June 18, 2026, FERC issued a Section 206 show cause order to ISO-NE and its participating transmission owners, preliminarily finding the grid operator’s tariff unjust and unreasonable for failing to address large load interconnection and study processes, cost-shifting mitigation for required network upgrades, co-location service terms, flexible transmission options for load curtailment, and generation study rules for electrically proximate loads of 50 MW or greater. ISO-NE and transmission owners have until August 17, 2026, to submit responses justifying existing terms or proposing revisions, plus a 30-day informational report on generation availability for large loads. Stakeholders may weigh in on filings within 30 days of submission, and parties may request a 90-day abeyance to develop formal Section 205 tariff changes via stakeholder processes.