A public utilities commission proposes prioritizing data center load curtailment over residential customers during grid emergencies.

Pennsylvania regulators are proposing new safeguards that could require major electricity users, including data centers, to curtail their power demand before homes and smaller businesses when the electric grid faces strain. The Pennsylvania Public Utility Commission voted unanimously (4-0) on Wednesday to seek public comment on the proposal, which responds to rapid data-center development adding significant new demand to the regional power grid.

Under the tentative order, new large-load customers that have not secured sufficient additional electric capacity to support their demand could be subject to curtailment before other customers during periods when additional reductions are needed to maintain grid reliability. The proposal would also prevent electric distribution companies from classifying large loads—such as data centers—as critical users exempt from reductions during pre-emergency or emergency events.

An independent analysis commissioned by the PUC found that growing electricity demand, driven largely by data centers, could create serious reliability concerns if new power supply does not keep pace. Under the study's reference scenario, the regional grid would fail to meet PJM reliability standards from 2027 through 2030.

The proposed rules would require utilities to maintain a registry of major power users, establish procedures to notify eligible customers of possible curtailments, and prioritize reductions for certain large new loads during an Interim Resource Adequacy Service event called by PJM. The commission is also considering how to ensure major users requiring 50 megawatts or more pay the costs they add to the electric system rather than shifting those costs to other ratepayers.

The tentative order will be published in the Pennsylvania Bulletin, beginning a 30-day public comment period, with reply comments due 15 days thereafter. The PUC expects to consider a final order at its January 28, 2027 meeting.