Scorching temperatures pushed electricity demand to near record levels as parts of the eastern U.S. endured temperatures in excess of 100 degrees during last week’s heat wave.
Electricity demand hit its second-highest level ever Thursday evening in the power grid serving the mid-Atlantic region. Demand in the Midwest, meanwhile, crested at its highest level in at least 10 years last Tuesday. And grid operators in New York and New England issued alerts to consumers asking them to conserve electricity as they grappled with elevated demand.
The grid’s performance has garnered heightened attention amid concerns over rising power demand from data centers and the threat of climate change. Power flowed throughout the recent heat wave, though localized outages were reported in Michigan, New York and Wisconsin.
Much of the focus centered on the PJM Interconnection, a grid serving 67 million customers across 13 mid-Atlantic states at the center of the country’s data center boom. Power demand hit 162 gigawatts around 6 p.m. on July 2 — the second-highest level ever recorded by PJM. Demand likely would have surpassed the record of 165 GW set in 2006 had the grid operator not implemented a program that pays large energy consumers to reduce consumption, PJM said on its website.
The grid operator received emergency authorization from the Energy Department to direct data centers to switch to backup generation, but ultimately did not utilize the authority, said Jeffrey Shields, a PJM spokesperson.
Mark Christie, a Republican who served on the Federal Energy Regulatory Commission and is a former Virginia utility regulator, said the grid’s performance prompted him to do something that was “very rare.”
“I want to praise PJM,” he said. “It was a tremendous challenge, and they met it.”
PJM has become a political punching bag for Democrats and Republicans alike for its failure to keep pace with rising electricity demand, Christie said. Virginia’s largest utility, Dominion Energy, has 70 GW of data center load that it’s trying to connect to its system, he added.
“Add 70 GW to what happened in this heat dome, and you’re nowhere near meeting demand,” Christie said.
Yet PJM showed that it was able to manage surging demand in extremely challenging conditions, as temperatures in large load centers like Washington, Philadelphia and Newark crested above 100 degrees on July 2.
Another grid manager, the New York Independent System Operator, issued an energy watch on Wednesday as high temperatures led to reduced generating reserves. But the Empire State’s grid largely navigated the heat wave without incident. Demand peaked around 31 GW at 7 p.m. on July 2, according to preliminary electricity data maintained by the U.S. Energy Information Administration. Localized power outages were reported in New York City, where Consolidated Edison was forced to shut off electricity to 9,800 customers due to extreme heat.
In the Midwest, high temperatures peaked two days earlier. The 121 GW of demand reported by the Midcontinent Independent System Operator on June 30 at 5 p.m. was the highest level in at least a decade, according to EIA data, which goes back to 2016. MISO reported an all-time peak of 127 GW in the summer of 2011.
Climate scientists say heat waves have become more frequent and severe as the planet warms, presenting a challenge to grid infrastructure. Much of the recent political debate has focused on building infrastructure needed to support the growth of data centers and artificial intelligence, said Richard Glick, a Democrat who served as chair of FERC. But comparatively less attention has been paid to climate change.
“We need to figure out how to meet the demands of low growth, but also extreme weather,” he said.
