FERC Puts All Six Grid Operators on the Clock for Data Center Connections

The Federal Energy Regulatory Commission had promised to act on large load interconnection by June 2026, and on June 18 it did, though not in the form many expected. Rather than issue a single national rule out of the advance notice of proposed rulemaking that the Secretary of Energy directed it to consider in October 2025, the Commission issued six tailored show cause orders under section 206 of the Federal Power Act, one to each of the regional transmission organizations and independent system operators it regulates: PJM, MISO, SPP, CAISO, ISO New England and NYISO.

Each grid operator and its transmission owners now have 60 days to do one of two things. They can explain why their existing tariffs remain just and reasonable without provisions written specifically for large loads, or they can file tariff changes that address the issues the Commission identified. The first is efficient transmission service application and study processes, including consideration of alternative transmission technologies. Read together, those categories describe a fairly complete agenda for how a data center should connect to an organized market.

A large load should be able to get a timely answer on whether and when it can connect. The ANOPR docket, RM26-4-000, defined large loads as demand greater than 20 MW and asked whether flexible loads could be studied within 60 days, among other questions. Retail service, including the decision to serve a new customer, is a state matter. It directs ISO-NE to explain whether its tariff adequately addresses interconnection customers serving electrically proximate or co-located load, and it raises the Commission's concern about ISO-NE's need to ensure adequate generation for new large loads.

They will, however, put each operator's plan on the record in a way that can be compared, and they may shape the next round of Commission action if the plans look inadequate. Operators that choose to justify their existing tariffs will need to argue that general interconnection and transmission service rules already handle large loads well enough.