Blackout risk climbs as heatwave strains largest US power grids
Intense heat is pushing electricity demand toward record levels across the US midwest and mid-Atlantic on Wednesday, prompting grid operators to warn of possible outages.
The US Department of Energy warned on Wednesday of an elevated risk of power outages across PJM Interconnection, the country's largest electric grid, which supplies roughly 67 million people in a region stretching from Washington DC to Chicago. The warning comes as extreme heat strains electricity supplies across a wide swath of the midwest and mid-Atlantic.
Late Tuesday, Energy Secretary Chris Wright authorized PJM to call on backup generation as a last-resort measure before moving to declare a level three emergency alert, one of the final steps before rotating blackouts could be ordered. The department said the action was intended to stabilize the mid-Atlantic grid and reduce the chance of outages.
Forecasters expected temperatures in Chicago, St Louis and Washington DC to climb past 32C (90F) during Wednesday's period of peak electricity use. Early Wednesday, PJM issued a maximum generation emergency alert, instructing generators currently offline for planned maintenance to report how quickly they could resume operation.
Midwest grid also nearing record demand
Separately, the Midcontinent Independent System Operator (Miso), which coordinates the grid across 15 midwestern and southern states, forecast Wednesday's peak demand would approach roughly 121 gigawatts, close to its all-time record of 127.1 GW. Miso said it was raising its standard reserve requirement as a safeguard against unplanned plant outages and congestion on transmission lines.
In rural Missouri's Ozark region, the Howell-Oregon Electric Cooperative urged customers to unplug chargers and appliances not in use and to consider raising thermostat settings to cut back on air conditioning during the ongoing heat.
