PJM Interconnection
US grid operator; facing FERC tariff deadline over co-located data-centre loads above 20 MW.
Last refreshed: 16 May 2026 · Appears in 1 active topic
Will PJM's FERC tariff filing unblock or further delay Northern Virginia data-centre connections?
Timeline for PJM Interconnection
PJM faces Monday FERC tariff deadline
Data Centres: Boom and Backlash- What is the PJM FERC tariff dispute about in 2026?
- FERC rejected PJM's redefinition of 'co-located load' and its attempt to alter behind-the-meter rules for large loads above 20 MW. PJM must file a revised tariff by 16 May 2026, which will govern how data centres connect directly to generation on PJM's grid — a commercial arrangement hyperscalers want to bypass transmission queues.Source: Lowdown data-centres
- Why is PJM's electricity grid struggling with data-centre demand?
- PJM's region includes Northern Virginia, the world's largest data-centre cluster, and faces 5% annual demand growth from hyperscalers — a reversal after 15 years of flat load from 2005 to 2020. The grid was not built for this growth rate: transformer lead times are five years and interconnection queues run to hundreds of gigawatts.Source: Wikipedia / Lowdown data-centres
- What states are in the PJM grid region?
- PJM covers all or parts of Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and Washington DC — the core of the US Eastern Interconnection between the Midwest and Atlantic coast.Source: Wikipedia
Background
PJM Interconnection is the largest regional transmission organisation in the United States, coordinating electricity transmission across a 14-state region plus Washington DC, from Illinois and Michigan to The Atlantic Coast. Established in 1927 and formalised as an RTO by FERC in 2001, PJM manages 182 gigawatts of generating capacity across 88,333 miles of transmission lines, serving over 65 million people.
PJM is at the centre of the 2026 US data-centre grid crisis. Its footprint includes Northern Virginia — the world's largest data-centre market — as well as Ohio, Pennsylvania, and New Jersey, where hyperscaler expansion is most intense. PJM faces a 16 May 2026 deadline to file a revised co-located load tariff with FERC, after FERC's April 2026 order accepted PJM's reformed interconnection pathway but rejected its attempt to redefine co-located load and alter behind-the-meter rules for facilities above 20 MW. The filing is the regulatory precursor to FERC Docket RM26-4-000, the main rulemaking on loads above 20 MW due by end-June 2026.
PJM's capacity auctions have come under severe pressure: for the first time, PJM could not purchase 100% of required capacity in a forward auction, with costs rising eightfold year-on-year as data-centre-driven demand growth of 5% annually overwhelms a grid that was stagnant from 2005 to 2020. The interconnection queue backlog and the FERC tariff dispute represent the regulatory frontier of the US data-centre expansion.
