Data centers

What a data center is

A data center is a building full of computers that store, process, and move digital information. Every website you visit, every file you save to the cloud, and every AI query you run lives on servers inside one of these facilities, running around the clock.

The scale has changed sharply. A large modern data center, often called a hyperscale facility, can cover more than a million square feet and hold tens of thousands of servers. The Lawrence Berkeley National Laboratory reported in December 2024 that there are more than 5,000 data centers in the United States, more than any other country in the world. Virginia holds the densest cluster on the planet, with Loudoun County nicknamed "Data Center Alley" for handling a large share of global internet traffic. Texas, Georgia, Arizona, and Ohio are all seeing rapid construction, drawn by cheap land, tax incentives, and access to power.

How data centers consume energy

The electricity a data center uses goes to 2 main jobs: running the servers and keeping them cool. Servers generate enormous heat as they process information, and that heat has to be removed constantly or the equipment fails, so cooling can account for up to 40% of a facility's total energy use, the Department of Energy reports.

Artificial intelligence has raised the demand steeply. Training and running AI models takes far more computing power than traditional web services, and each rack of AI chips draws several times the electricity of a standard server rack. A single ChatGPT query uses roughly ten times the electricity of a Google search, according to the International Energy Agency. Goldman Sachs Research projected in 2024 that data center power demand would grow 160% by 2030, driven largely by AI. The buildings run at full capacity 24 hours a day, seven days a week, which means their draw on the grid never eases the way home or office demand does overnight.

Cooling those servers takes water as well as electricity. Many large data centers use evaporative cooling, which sprays or circulates water to carry heat away, and that water evaporates into the air rather than returning to a river or reservoir.

The volumes are substantial. A large data center can use between 1 million and 5 million gallons of water a day, roughly what a town of 10,000 to 50,000 people uses, according to researchers at Virginia Tech. A 2021 study led by Shaolei Ren at the University of California, Riverside, estimated that US data centers directly consumed about 449 million liters of water a day, and far more indirectly through the water used to generate the electricity they run on. Much of this construction is happening in the drier parts of the country. Arizona, Nevada, and Texas all combine cheap land and tax breaks with strained water supplies, which places new data centers in direct competition with households and farms for a shrinking resource.

How data centers affect the local environment

A data center changes the environment around it in several ways at once. The most direct is grid strain. When a facility drawing hundreds of megawatts connects to a regional grid, it raises demand for everyone on that grid, and utilities often respond by keeping older fossil fuel plants running longer or building new gas capacity to meet the load.

That decision reaches the air. In Northern Virginia, the surge in data center demand has been tied to plans for new natural gas plants, and a 2024 analysis by the nonprofit organization PJM Interconnection, which manages the grid across 13 states, warned that rising data center load was outpacing the retirement of older, dirtier plants. Backup generation adds another layer, since most large data centers keep banks of diesel generators on site to run during outages, and those generators release nitrogen oxides and fine particulate when tested or used. Noise is a growing complaint too. The constant hum of cooling systems and generators runs day and night, and residents near facilities in Virginia and Arizona have reported a persistent low-frequency drone. Heat is the final effect, as the buildings release the warmth they pull off their servers into the surrounding air.

How data centers connect to household energy and environmental health

The link between a data center and your home runs through the electricity bill and the power plant. When data centers drive up regional demand, the cost of building new generation and transmission often lands on all ratepayers, not just the companies running the servers. A 2024 report from the consumer advocacy group Public Citizen found that residential customers in several states were beginning to shoulder infrastructure costs tied to data center growth, raising monthly bills for households that never use the facilities directly.

The environmental connection is just as real. A data center that keeps a gas or coal plant running longer adds to the same particulate matter and ozone that reach into homes and trigger asthma and heart problems. The water a facility evaporates in a drought-stressed region is water pulled from the same supply that fills household taps. And the electricity demand competes with the broader shift toward clean energy, since power used to run servers is power not available to decarbonize homes, cars, and industry. The buildings sit at the intersection of nearly every household energy and environmental concern, quietly raising the stakes on all of them.

The households nearest to data center construction feel the effects first. Residents in fast-growing clusters like Loudoun County, Virginia, and parts of central Ohio face the noise, the air quality effects of new gas generation, and the pressure on local land and water. Many of these communities had little say in the siting decisions, which are often negotiated between developers and local governments drawn by the promise of tax revenue.

Lower-income communities and communities of color carry added risk, following the same pattern seen with other polluting infrastructure. New gas plants and generators are more likely to be built or expanded near neighborhoods with less political power to oppose them, exposing residents to the particulate and ozone that worsen asthma and heart disease. Households in drought-prone states bear the water burden, competing with facilities that consume millions of gallons a day. And ratepayers across entire regions absorb the cost, since the infrastructure built to serve data centers is frequently paid for through rates charged to every customer on the system. The people who benefit least from the servers often pay the most for them.

What a household can do

Start by understanding the connection, because the effects of data centers are easy to miss when the buildings are unmarked and the costs are buried in a utility bill. Read the rate cases and infrastructure proposals your state public utility commission publishes, since these decisions determine whether households or the companies driving demand pay for new power plants and transmission lines. Public comment periods on these proposals are open to residents, and utility commissions in several states have begun weighing whether large users should carry more of the cost.

Pay attention to local siting decisions where you live, since data centers are typically approved at the county or city level, often with tax incentives that shift the tradeoffs onto residents. Attending a zoning or planning meeting is one of the few points where a household has real leverage over whether a facility is built nearby and under what conditions. Reduce your own digital footprint where it is simple, since streaming in lower resolution, deleting unused cloud storage, and limiting unnecessary AI queries all lower demand at the margin, though individual use is a small share of the total. Support clean energy at home through efficiency upgrades, rooftop solar where it makes sense, and utility green power programs, since the faster the grid decarbonizes, the less a data center's demand ties the region to fossil fuel plants. And press elected officials and utility regulators on transparency, since companies are not always required to disclose how much water and power a facility uses, and public pressure has already pushed some states toward requiring it.