Energy Department authorizes PJM to direct backup generation

Miso projects Wednesday peak demand near its all-time high of 127.1 gigawatts

The US Energy Department on Tuesday evening authorized PJM Interconnection, the operator of the nation’s largest power grid serving 67 million people, to direct backup generation as the Energy Department warned of the potential for heightened blackout risks across the mid-Atlantic and midwest.

Energy Secretary Chris Wright’s late-Tuesday authorization allows PJM to direct backup power resources to operate “as a last resort before declaring a level three energy emergency alert,” the department said. A level three alert can be one of the last steps before rotating blackouts are ordered. The Energy Department described the move as part of a plan “to stabilize the Mid-Atlantic grid and mitigate the risk of blackouts.”

“Maintaining affordable, reliable, and secure power for hardworking American families and businesses during periods of hot weather is non-negotiable,” Wright said in a statement.

The Energy Department’s warning covered the PJM system, which stretches from Washington DC to Chicago and serves 67 million people across the mid-Atlantic and midwest. Temperatures in Chicago, St Louis and Washington DC were expected to rise above 90F (32C) during peak electricity demand on Wednesday.

PJM separately issued a “maximum generation emergency” alert, in effect early Wednesday, directing generators on planned outages to report how quickly they could return units to service.

The Midcontinent Independent System Operator, known as Miso and serving 15 states in the Midwest and the South, projected Wednesday peak demand near record territory at approximately 121 gigawatts, against its all-time high of 127.1 gigawatts. Miso’s forecast covers a separate grid footprint from the PJM alert.

Miso warned of tight conditions and increased its normal reserve requirement as a buffer against unexpected power plant outages and transmission line congestion.

In the Ozark region of rural Missouri, the Howell-Oregon Electric Cooperative advised customers to unplug unused chargers and appliances during the continued extreme heat. Customers were also asked to consider raising their thermostats to reduce air conditioning use.

The Guardian reported the developments.