The U.S. Department of Energy has authorized the nation’s largest electricity grid operator to deploy backup diesel generators at data centers to prevent blackouts during a dangerous heat wave.
Energy Secretary Chris Wright signed the order Tuesday, granting PJM Interconnection permission to tap diesel backup generators, battery arrays, and other resources as a last resort to keep the grid stable.
PJM’s territory stretches from Washington to Chicago and covers Maryland, Washington D.C., and more than a dozen other states, making the stakes of a grid failure extraordinarily high.
The move comes as Virginia’s data center corridor, known as Data Center Alley, faces a severe test from surging electricity demand driven simultaneously by air conditioning use and data center operations.
PJM is projecting demand to peak Thursday at 166,304 megawatts, which would break the previous grid record of 165,563 megawatts set in 2006, with temperatures expected to reach between 102 and 104 degrees Fahrenheit through Saturday.
“Currently, there are tens of gigawatts of readily available backup generation that have remained largely untapped,” Wright wrote in his order, adding that deployment “can prevent avoidable blackouts, thereby saving lives and reducing costs to the American people.”
The order also permits power generating facilities to exceed their normal pollution limits if necessary, with PJM required to notify the Department of Energy whenever generation resources are pushed beyond their environmental allowances.
PJM officials have acknowledged the order could result in exceedances of sulfur dioxide, nitrogen oxide, carbon monoxide, ammonia levels, and wastewater releases, with the authorization set to expire at 11:59 p.m. on July 3.
Virginia sits at the epicenter of the nation’s data center expansion, with state regulators having permitted more than 8,000 diesel generators at data center facilities in recent years, according to data from the state Department of Environmental Quality.
Diesel generators release emissions that the EPA has categorized as a “possible human carcinogen,” and the backup units lack the air pollution controls typically required to protect public health in surrounding communities.
Climate scientist Kim Cobb of Brown University said extreme heat events were already straining grids before the data center boom intensified the problem, warning that “even a modest increase in baseline temperature causes an exponential increase in heat extremes.”
“You find yourself crossing these heat extremes much more frequently,” Cobb added, describing the current situation as “exactly what we expect in a warming world.”
Residents living near data center facilities in Virginia have expressed frustration at being caught between the threat of blackouts and exposure to diesel pollution, with one resident capturing the dilemma bluntly.
“Either way, we are screwed,” the resident said. “Either our lights go out or we get to breathe in this pollution.”
The tension is not new in Loudoun County, where last June residents turned to Reddit to ask questions about dark gray plumes of smoke rising from data center facilities during a prior heat event as temperatures climbed into the 90s.
Aaron Tinjum, vice president of energy for the Data Center Coalition, said facilities in the region “will work closely with utilities and grid operators, using backup power if directed and where appropriate to reduce strain on the grid.”
PJM updated its emergency procedures recently to account for the rapid growth of data centers, treating backup generator activation as a measure of absolute last resort following consumer energy-reduction requests.
The DOE has issued comparable emergency orders in recent months, including before Winter Storm Fern last winter and ahead of a separate heat wave in May, signaling that such interventions are becoming a more regular feature of grid management.
