[DigitalToday reporter Chi-gyu Hwang (황치규)] PJM Interconnection, the largest U.S. grid operator, will cut supply to large data centres and other big power users when electricity is in short supply. The move follows a capacity auction to add new generation that fell short of its target, IT outlet TechCrunch reported on Monday.

The supply restrictions will take effect from June 2027. They will apply to data centres that use 50 megawatts (MW) or more. PJM is also holding an additional auction to secure new generation capacity.

The measure will operate similarly to demand response programmes that large customers such as manufacturers have taken part in. Customers whose power supply is reduced will receive compensation. The advance notice period can vary from 30 minutes to several days, depending on demand forecasts.

With data centre construction surging, grid operators are under pressure to secure enough electricity to meet rapidly rising data centre demand. Data centre electricity consumption is expected to quadruple by 2035 from current levels.

The move increases the likelihood that new data centres and some existing facilities will seek on-site power sources. Sites without their own power sources could rely more on backup generators. Such equipment often costs more to run and can be more polluting.