PJM will begin curtailing large data centers during shortages starting June 2027, if needed.
Why it matters: The move is a direct warning to AI and cloud operators that power access is becoming an operating constraint, not just a planning issue. It could affect where hyperscale data centers are built, how they are permitted and what backup power arrangements they need.
- PJM Interconnection says it will start cutting power to large data centers in June 2027 if reliability is at risk.
- The curtailment would apply to data centers with loads of 50 megawatts or more.
- Affected customers would be compensated under a demand-response style program, according to PJM.
- PJM serves about 67 million customers across 13 states from Virginia to Illinois.
PJM Interconnection, the largest U.S. grid operator, says it plans to curtail large data centers during power shortages starting in June 2027 if needed to protect reliability on its system, according to reporting from TechCrunch.
The curtailment would apply only to data centers with loads of 50 megawatts or more. PJM says customers affected by the program would be compensated, using a demand-response style structure. PJM describes demand response as a voluntary program that pays customers to reduce electricity use when requested during high prices or reliability threats.
The warning comes as PJM says its capacity auction fell short of its reliability requirement, a sign that supply is not keeping pace with forecast demand growth. In its annual report materials, PJM said its 2026/2027 Base Residual Auction missed the reliability requirement by 6,517 megawatts. PJM's annual report page also says the grid operator is facing a supply-demand gap as load grows.
PJM has been warning throughout 2026 that rapidly growing data-center demand is outpacing new generation and transmission. In January, it outlined plans to integrate large loads more reliably in a board release.
The grid operator serves about 67 million customers across 13 states from Virginia to Illinois. Reuters also reported on July 22, 2026 that a large data-center power disconnect on PJM's grid caused a voltage disturbance, though not a reliability impact.
By the numbers
- 50 megawatts - PJM says the curtailment would apply to data centers at or above this load.
- 6,517 MW - PJM says its 2026/2027 Base Residual Auction fell short of the reliability requirement by this amount.
- 67 million - PJM says it serves about this many customers across 13 states.
Yes, but: The exact framework still leaves open whether the program will cover only new interconnections, existing loads, or both, and PJM has not publicly detailed all of the safeguards.
What's next: PJM says curtailment would begin in June 2027 if needed.