Energy producers and distributors are quick to point out that America’s overall power usage has plummeted since the onset of the COVID-19 pandemic, thanks to the shuttering of large commercial and industrial buildings. But those structures usually sit on the most capacious portions of an urban electrical grid, said Dr. Yury Dvorkin, assistant professor at New York University’s Tandon School of Engineering. By contrast, the power infrastructure in residential areas is typically designed to accommodate heavy use in the early mornings and evenings, with hours to cool off during the day. Consumption patterns in these districts have already changed during the crisis, with demand spiking in the daytime. Overall usage is already up by an average of 7 percent in New York City apartments, and by 15 to 20 percent in homes in California.

As the summer heat peaks, and juice-sucking air conditioners remain on through the afternoon, the risk of failure in aged transformers and other equipment increases.

“The fact that Lower Manhattan is using less power is not going to help to deliver power to people in Queens, many of whom for health reasons may be intolerant to high temperatures, and whose buildings are connected to a very old transmission line with limited margins to carry extra power,” said Dvorkin. “What’s going to happen this summer, if we have stay-at-home orders, if we have consumption which the grid was not designed to accommodate, it will push the system to its limits.”