As heat waves strain power grids, data centers become flashpoints in AI debate
LOWELL, Mass. (AP) — Eileen Castle's swimming pool, one of the only ones for blocks around, was once a refuge for neighborhood children on hot summer days.
But even as temperatures soared this week, Castle, 82, said she won't be filling the pool — not with the data center behind her house buzzing with the sound of its industrial air conditioners and its backup diesel generators belching fumes at unexpected times.
“I think about the air quality, the water, what effects it has on the kids in the area,” she said on her front stoop as children whirred past on bicycles.
The kind of heat wave sweeping the eastern U.S. this week doesn't just make people uncomfortable — it drives up electricity demand for data centers, adding to their strain on power grids and worsening air quality for surrounding neighborhoods. For communities like the racially diverse Sacred Heart area in Lowell, Massachusetts, the impact underscores why the artificial intelligence industry is facing growing scrutiny over the fast-spreading facilities.
Across the country, data centers have been blamed for a host of environmental ills, from high water consumption to diesel exhaust to pressure on local energy infrastructure. Some tech industry figures argue the facilities have become lightning rods for broader anxieties about the economic and societal shifts triggered by the AI boom.
But on sweltering days, the effects are hard to ignore in Castle's neighborhood, which the state has designated as facing higher environmental and health risks due to a population historically excluded from political decision-making.
“It’s majority low-income and working families — people working hard every day just to put food on the table,” said state Rep. Tara Hong, a Democrat who represents a heavily Cambodian American district in Lowell, a city of about 115,000 people northwest of Boston. “It’s an inclusive place, and that data center is just smack in the middle of everything.”
A heat wave is “almost the worst situation for data center operation,” said Shaolei Ren, a professor at the University of California, Riverside, who has studied AI’s environmental toll. Data centers house racks of computer servers that run hot, and keeping them cool requires either energy-intensive refrigeration or water-intensive evaporative cooling, he explained.
When the grid gets stressed, data center operators sometimes fire up backup diesel generators as a “preventive measure” to reduce the risk of an outage. Ren called those generators “the last line of defense” for the grid — but noted that diesel emissions can harm human health even with short-term exposure. If too many generators run during a heat wave, he warned, it could be “a disaster for local air quality.”
The operator of the Lowell data center, the Markley Group, said it has planted more than 2,000 trees nearby to improve air quality. CEO Jeff Markley said in a statement to The Associated Press that the company has switched on generators in an emergency only a handful of times. “They are not run proactively or continuously; they engage only during an actual power disruption to keep critical systems online, plus brief weekly testing of about five minutes per unit, run one generator at a time,” he said.
Markley said he chose Lowell because of its abundant water for cooling — supplied by the same Merrimack River that powered 19th-century textile mills during the Industrial Revolution. He noted the Lowell facility uses about 118,000 gallons of water per day at the peak of summer, a small fraction of the city's daily consumption.
Castle, a lifelong resident, was among those who welcomed the Markley Group a decade ago when it first began building on the site of an abandoned Prince spaghetti factory. But about two years ago, when the company added a second cooling tank behind her above-ground swimming pool, along with a growing number of surveillance cameras, the relationship soured.
In response to growing opposition, Lowell's City Council voted 10-0 in February to pass a moratorium blocking further data center expansion for a year.
Data center electricity use has grown in the last few years, said Jonathan Koomey, a researcher who has studied the computing warehouses for 30 years. But it’s “very much a local phenomenon,” he said. On a national scale, Koomey said demand growth has been moderate in recent years and he doesn't expect that to change drastically. “This is not a national crisis. It's not explosive growth nationally,” he said. Still, he acknowledged that in communities surrounding data centers, environmental costs, local economic impacts, traffic and other concerns need to be accounted for.
When temperatures climb into triple digits — as they’re expected to this week in New England — it becomes harder to push heat out of a data center. Keeping it cool requires more power, just as with homes and commercial buildings. That can strain power grids and pose a “real risk” of outages, Koomey said. Unlike the typical summer AC rush, where operators manage “a lot of small loads” from individual homes, data centers represent large, concentrated loads. “One of the challenges that data center operators face is that these data centers are pretty big loads. They are big enough that they have to think about how to coordinate them and make sure that they're not all cutting off at the same time or coming on at the same time,” he said.
The North American Electric Reliability Corporation, a nonprofit that develops and enforces standards for the utility industry, recently issued an alert about “unprecedented challenges from a surge in large power consumers” and developed guidelines to mitigate the “immediate risks posed” by AI data centers.
Tensions ran so high in Lowell this week that police officers temporarily detained a 14-year-old girl who spoke out of turn at a city-led community forum on data center zoning. “I'm not hurting anyone,” the girl shouted Monday after police officers escorted her from a middle school auditorium. “We just don't want data centers!”
A coalition of data center opponents is increasingly clashing with electricians employed by Markley and other data center backers who say the facility boosts Lowell's ties to the tech industry. Criticized for calling police to the contentious meeting and later asking an officer to remove the girl, Lowell Mayor Erik Gitschier, whose office is nonpartisan, told local talk radio station WCAP he didn't know her age at the time and defended his efforts to bring decorum to a topic he said deserves debate. “It was warm out,” he said. “You had people who had definite, passionate positions and they were screaming.”
___
Huamani contributed from New York.