Archived: AI Needs So Much Power, It’s Making Yours Worse

Every day, Americans reach into their refrigerators or turn on their dishwashers without much thought given to the electricity flowing through their homes. But a hidden problem now threatens these seemingly mundane tasks: distorted power supplies.

The term for the issue is “bad harmonics.” It may seem a bit esoteric, but you can think of it like the static that can be heard when a speaker’s volume is jacked up higher than it can handle. Electricity travels across high-voltage lines in waves, and when those wave patterns deviate from what’s considered ideal, it distorts the power that flows into homes. Bad harmonics can force home electronics to run hot, or even cause the motors in refrigerators and air conditioners to rattle. It’s an issue that can add up to billions of dollars in total damage.

More importantly, bad harmonics are symptomatic of much deeper problems that are engulfing the US grid.

What Harmonic Distortion Looks Like In Electrical Waves

Distorted waves are just one measure of broader power quality. When homes experience good, or stable, power quality, it means that the flow of electricity for lights and appliances is being delivered at an even and predictable pace. The worse power quality gets, the more the risk increases. Sudden surges or sags in electrical supplies can lead to sparks and even home fires. Left unaddressed, one problem can morph into another. That means the bad harmonics of today can be a sign of potential disaster down the road.

“Harmonics are a pretty good canary in the coal mine for early signs of stress and problems,” said Bob Marshall, chief executive officer of Whisker Labs Inc.

Whisker Labs tracks power quality in real-time using roughly 1 million residential sensors, which are spread so widely across the country that nearly 90% of US homes are within half a mile of one. A Bloomberg analysis of exclusive sensor data coupled with data from DC Byte, a market intelligence firm, showed a strong link between proximity to data centers and worsening harmonics.

More than half of the tracked households showing the worst distortions of power quality are located within 20 miles of significant data center activity, according to the analysis, which covered readings from February through October. US census figures show that about 3.7 million Americans live in the most-impacted areas.

Power Distortions Are More Common Near Data Centers

Distance from data centers for sensors with the best and worst readings

Experts have been warning for some time now about the impact data centers will have on power grids across the globe. The AI boom has only underscored the issue: The digital economy is sucking up so much power that demand is now straining available supplies of electricity in many parts of the world, leading to concerns over price increases and even widespread outages. And that’s only projected to worsen as more data centers are built.

The new harmonics data shows how these problems are already starting to play out in real time across the US.

Read More: AI Is Already Wreaking Havoc on Global Power Systems

It’s an issue that goes beyond just whether or not there’s enough power to flip the lights on. Distortions mean that even as electricity is flowing to homes, the quality can be eroded enough to destroy appliances and increase vulnerability to electrical fires if there’s a voltage surge. Poorer power quality overall can also eventually lead to lights flickering along with brownouts and blackouts.

“We need to understand those risks,” said Hasala Dharmawardena, a senior engineer of power systems modeling studies at the North American Electric Reliability Corp., where he is part of a team looking at data centers.

The grid has never faced the kinds of strain that comes with data centers. These city-sized users can pop up very quickly, within a year or two, which is much faster than grid planning usually happens. Even during population booms, the rise in power demand paled in comparison to the expected installation in the coming years of hundreds, perhaps thousands, of these facilities to power AI. That stress is adding to problems of aging infrastructure, extreme weather and the electrification of more parts of everyday life, such as the rise of electric vehicles.

It’s especially important to understand the power system impact from AI “because it is such a big hammer” on the grid, Dharmawardena said. “The data center is a very large load. Take your house and increase that by 10,000. That is the difference between your house and a data center.”

The US today is by far the largest operator of data centers in the world, with Northern Virginia’s hub boasting more than twice as much operational capacity as Beijing, its next-biggest rival, according to estimates from Bloomberg Intelligence. But other countries are racing to build out their own facilities, with growth expected in nations including Saudi Arabia, Ireland and Malaysia, which will all face their own pressures on domestic power systems.

The problems in the US are compounded by the fact that not enough investment has gone into the grid to fortify it for the coming demand boom. For decades, US power use was largely flat. Now, it’s about to be turbocharged. The nation’s demand for electricity will surge almost 16% over the next five years, more than triple the estimate from a year ago, driven largely by new data centers, according to a recent report from Grid Strategies, a DC-based consulting firm.

The increase means that without major improvements to the grid and power equipment, harmonics issues seen today are likely to get worse.

Some of the biggest data-center clusters are near big cities, so that the facilities can tap into larger grids and the fiber networks that are often located close to consumers for latency issues. That underscores why harmonics are often worse in urban areas. But while the effect appears to be more severe where population density is higher, Bloomberg’s analysis shows that even in rural areas, sensors that are closer to significant data center activity are more likely to have distorted power.

Data Center Effect Seen in Both Urban and Rural Areas

Median distance from data centers for sensors with most distorted and least distorted power

Other factors, like solar energy generation, the deployment of EVs and swings in industrial loads can all contribute to irregular wave patterns. Still, a Bloomberg analysis found that sensors with more distorted power weren’t necessarily closer to large-scale solar installations. While the Whisker Labs data itself doesn’t point to a single cause for power distortions, the correlation between bad harmonics and data-center proximity is too strong to be coincidental.

Bad harmonics occur when electrical currents stray from moving in a perfect wave pattern at a rate of 60 revolutions per minute. The acceptable limit for deviations from that pattern for local lines are set based on industry engineering standards. Sustained distortions topping 8% from the ideal pattern can reduce efficiency and degrade equipment faster.

In hot spots like Chicago and Dallas, harmonic readings are consistently showing signs of concern.

More than a third of the Whisker Labs sensors in the Chicago area showed sustained high average readings over nine months. The surrounding county had about 16,000 sensors through October, of which more than 9,300 had at least one monthly reading of 8% or more. The metropolitan region also has more long-standing power quality issues that go beyond harmonics.

The harmonics data in Bloomberg’s analysis was measured through Whisker Labs Ting devices, which track total harmonic distortion inside individual homes and show on a granular level how electricity is being delivered to residences — the data also goes deeper than what utilities are typically required to collect and report to regulators. That can explain why there’s sometimes a discrepancy between the company’s data and what power providers are observing, because they aren’t seeing the home-level distortions.

The Chicago area is served by Exelon Corp.’s Commonwealth Edison utility.

“ComEd strongly questions the accuracy and underlying assumptions of Whisker Lab’s claims,” utility spokesman John Schoen said in an email. “Ting devices are installed in the home and do not directly measure harmonics on the grid,” he said, adding that the utility meets power delivery standards set by the Illinois regulator and that the company’s data, which is taken from system equipment, disputes the Whisker Labs data. ComEd declined to share that data with Bloomberg News.

While distortions on the level of individual homes can be related to issues within that residence, Bloomberg’s analysis showed that worse harmonics were typically observed across multiple sensors in the same area, which Whisker Labs has said is more likely to indicate grid problems rather than issues from inside a home.

Harmonics, along with power-quality issues more broadly, “is another element in these perfect storm scenarios we are not monitoring and addressing quickly and efficiently enough,” said Thomas Coleman, CEO of consultant Structure Energy Solutions and a long-time expert on grid reliability.

Almost nowhere are the correlations between data centers and bad harmonics as clear as in an area of Northern Virginia that’s been dubbed “data center alley,” the global center of the industry. The area is mostly located in Loudoun County, outside of Washington, DC, which saw its data-center capacity increase by 2% in 2024 to about 3,000 megawatts (MW).

Nationally, the data analysis showed that roughly 1.7% of sensors in the average county had at least one monthly reading that exceeded the 8%-threshold for bad harmonics. That share was more than four times higher in Loudoun County.

Neighboring Prince William County added 240 megawatts worth of data centers this year, for a total capacity of more than 1,000 megawatts. About 6% of the 1,100 sensors plugged into homes there had too-high distortions, nearly all within 7 miles of significant data center activity. Two dozen of those sensors had double-digit readings, with some of them reaching as high as 12.9%.

Meanwhile, a couple hundred miles away in York County, outside Colonial Williamsburg, Whisker Labs data shows steady, low harmonics, averaging less than 3%. The nearest major data center activity is more than 80 miles from the area.

Harmonics Look Different In These Virginia Counties

Prince William County, which is part of “data center alley,” had consistently higher levels of harmonic distortion over a three-month period than York County, which has no data centers

Much of “data center alley” is served by Dominion Energy Inc.’s Virginia utility.

Dominion hasn’t observed the distortion levels reported by Whisker Labs — and the utility’s measurements consistently show it is within industry standards, spokesman Aaron Ruby said in an email. The utility monitors power quality continuously through 200 devices across its system. “In a few rare instances, we have observed very brief periods of higher-than normal- harmonic disruption due to abnormal configurations or equipment issues when a new installation first comes online.” Immediate action was taken to resolve those issues, he said.

With more data facilities in the works to support AI, there’s an urgency to better understand what their impact will be, said Aman Joshi, chief commercial officer of Bloom Energy Corp., a fuel cell developer that has been researching how to stabilize the grid to enable data center growth. AI’s energy consumption is volatile and more akin to a sawtooth graph than a smooth line, which most data center operators had been used to until now.

“No grid is designed to be able to handle that kind of load fluctuation not only for one data center but for multiple data centers at the same time,” Joshi said. Earlier this year, Bloom published a white paper about how operations at these facilities can create power frequency and voltage fluctuations that inevitably affect other consumers

Anytime there’s a big swing in energy supply or demand it can create stress on the grid. With more granular-level readings of what is happening with harmonics on the residential level, it becomes easier to understand the risks to households, said Carrie Bentley, CEO of Gridwell Consulting.

“If you know it exists, it is easy to fix,” she said. “So if this is a problem, it is a nice problem.”

Some solutions are already in the works.

Northern Virginia Sees Power Distortions Near Data Centers Set to Expand

A data center hotspot near a community that routinely experiences significant power distortions. Prince Williams County, VA, 2024.

Most new data centers in Virginia require their own substation and transformer to be able to come online and this isolates them from nearby distribution circuits, limiting their impact on other customers, Dominion spokesman Ruby said. The Virginia utility is building a new transmission line into Loudoun County to address power quality and reliability constraints overall. Devices like filters and capacitors can help address harmonics issues around data centers.

Dominion serves most of the Loudoun data centers, and the remaining facilities there and in Prince William County are supplied through dedicated substations connected to the utility operated by the Northern Virginia Electric Cooperative. This separates supplies between data centers from equipment sending power to homes. “So harmonics generated by either customer class would not impact the other,” Lisa Hooker, a spokeswoman for the cooperative, said in an email.

But still, there’s a big hurdle when it comes to measuring the problem, which thus makes it challenging to address, according to more than half a dozen experts interviewed by Bloomberg News. Most utilities don’t have the capacity to track on the residential level because it would be too costly, said Dharmawardena of the North American Electric Reliability Corp.

A NERC task force focused on modeling data centers and other big users plans to release an analysis in 2025 for impacts on the transmission system. Oversight of local distribution systems under stress often fall to state regulators and utilities.

Dharmawardena compared bad harmonics to trash in the middle of the road, which can impact all drivers in the area. And the Whisker Labs data, he said, gives you a sense of “the overall condition of the road itself.”

“Embedded in your contract with your utility is the right to receive a certain quality of power,” he said. “We need to make sure we measure it, and that our consumers get the power quality that they deserve.”