ISO-NE

FERC issued ISO-NE a Section 206 show-cause order on 18 June 2026, directing it alongside the other five US Regional Transmission Organisations to justify or reform its large-load tariffs across five areas including co-location terms, study processes, and cost allocation. The same RM26-4-000 docket also requires ISO-NE and its five peer RTOs to file generation-adequacy reports by 20 July 2026, a nearer deadline than the show-cause responses. Responses to the show-cause order are due 17 August 2026, public comments 16 September, and any binding federal standard is deferred to 2027 at the earliest.

ISO New England (ISO-NE) manages the high-voltage electricity grid across six New England states: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It coordinates the region's wholesale electricity market and long-term transmission planning for a grid characterised by high renewable penetration targets, constrained winter natural gas supply (limited by pipeline capacity from the mid-Atlantic), and existing data-centre concentration in Massachusetts and Connecticut.

ISO-NE's show-cause response is relevant to data-centre operators evaluating New England sites as alternatives to congested Northern Virginia, though the region's higher electricity costs relative to the Midwest and South partially offset its proximity to financial and technology employment clusters. New England's transmission system is approaching the end of several ageing generation units' operating lives, adding reliability planning complexity to large-load integration at precisely the moment FERC is seeking tariff reforms and generation-adequacy assurances.