The first days of summer are stressing the nation’s power grid and prompting the Trump administration to let some power plants in the Southeast exceed emissions limits to help keep air conditioners humming.
Energy Secretary Chris Wright issued an order early Tuesday authorizing Duke Energy to run certain plants in the Carolinas on Tuesday and Wednesday to ensure adequate power supplies in the region as temperatures approach 100 degrees.
“Americans should not be forced to wonder if their power grid can support their homes and businesses,” Wright said in a statement. “This order ensures Duke Energy Carolinas can supply its customers with consistent and reliable power throughout peak summer demand.”
The order is the latest in a string of emergency actions by President Donald Trump’s Energy Department aimed at allowing fossil fuel plants to operate when they wouldn’t otherwise be idled or shut down. The actions come as power plant retirements, delays in getting replacement plants and power lines in service, and rising electricity demand increase the risk of outages.
The risk is exacerbated by more frequent extreme weather, including storms and extreme heat.
Much of the eastern U.S., from northeast Texas to New England, is baking in triple-digit heat and humidity this week thanks to a heat dome — an area of high pressure in the upper atmosphere that traps heat and humidity. Cities from St. Louis to Washington to New York were under heat advisories or warnings, according to the National Weather Service.
The high temperatures are expected to last at least through tonight for many areas and have prompted utilities to ask the customers to conserve energy.
Already more than 40,000 customers in several New York City boroughs lost power Monday as extreme heat and humidity stressed the local grid, according to utility Consolidated Edison. ConEd asked residents in the area to avoid running energy-intensive appliances such as washers and microwaves and to limit air conditioner use or charging electric vehicles until repairs were complete.
The utility said it reduced voltage by 8 percent in the area serving some customers in southeastern Queens.
Grid operators, too, are taking steps to ensure that power plants are available to run when needed.
Both PJM Interconnection, which operates the nation’s largest power market spanning the 13 mid-Atlantic and Midwest states, and the Midcontinent Independent System Operator, whose grid covers 14 central states, issued alerts to power plant and transmission owners.
The maximum generation warnings are initial steps taken by grid operators that instruct utilities to determine if any scheduled maintenance or equipment work can be delayed. The warnings also notify neighboring regions that power exports may be curtailed if capacity is needed locally.
PJM said it has sufficient reserves to meet forecast customer demand, which hit 161 gigawatts Monday, the highest level since 2011. PJM’s record summer peak load was set at more than 165 GW in 2006.
Carmel, Indiana-based MISO saw systemwide demand hit 120 GW on Monday, a high for the year but short of the all-time system peak of 127 GW in July 2011, spokesperson Brandon Morris said. He added that the scale of the grid operator’s 14-state footprint and location can provide advantages for preserving reliability.
“Because of our large, diverse footprint, MISO has several option — within our region and from our neighboring grid operators — to obtain emergency power and send it to where it is needed,” Morris said.
The early summer test for the nation’s power grid comes a month after the North American Electric Reliability Corp. warned that four regional power grids, including MISO, were at “elevated” risk this summer.
DOE’s emergency order issued Tuesday runs through 10 p.m. Wednesday, just after a heat advisory is due to expire.
The order allows Charlotte-based Duke Energy to run specific power plants in the Carolinas at maximum output over a two-day period to preserve grid reliability even if doing so results in exceeding emissions limits in operating permits.
The utility didn’t respond to a request for comment.
Such orders from DOE aren’t unusual in extreme conditions. In 2023, then-Energy Secretary Jennifer Granholm issued an emergency order aimed at keeping the lights on in Texas as the operator of the state’s main power grid coped with surging demand amid record-high temperatures.
While the near-term focus for grid managers and utilities is keeping air conditioners running, this week’s heat wave will have longer-term effects on consumers already seeing bills climb.
The U.S. Energy Information Administration on Monday said average residential electricity bills are expected to rise about 3 percent this summer to $178. EIA said the increase is being driven by higher power prices and expected to be mitigated by slightly cooler summer weather.
EIA noted, however, that weather is a wild card.
“If temperatures end up much hotter than expected, households are likely to face higher-than-expected increases in electricity bills, especially in the southern states,” the analysis said.
