Nvidia Cites 0.2% Water Figure as AI Data Centre Cooling Debate Grows

Nvidia has waded into the debate over how much water AI data centres consume, posting on social media that the industry accounts for just 0.2% of daily water use in the United States. The company cited figures from the Manhattan Institute, a US public policy think tank, and claimed that data centres’ share of national water consumption has “steeply decreased” thanks to more efficient cooling technology.

But independent research paints a picture with more detail — and more cause for scrutiny.

According to estimates from the University of Georgia Cooperative Extension, drawing on research by Mytton published in 2021, all US data centres combined consumed around 449 million gallons of water per day. Against a total US daily water consumption of 322 billion gallons, that works out at roughly 0.14% — close to, though not exactly matching, the 0.2% figure Nvidia referenced. The precise methodology behind the Manhattan Institute’s number, and the trend Nvidia describes as a dramatic decrease, couldn’t be independently verified against official US Geological Survey national statistics.

That distinction matters.

What Data Centres Actually Do With Water

Water isn’t used in data centres the way it’s used in a factory or a farm. It’s almost entirely about keeping servers cool. The dominant method is evaporative cooling — drawing in water, passing it through cooling towers, and allowing it to evaporate. Around 80% of the freshwater withdrawn for this purpose is estimated to evaporate entirely, with the rest discharged to municipal wastewater facilities.

A typical data centre uses about 300,000 gallons of water per day — roughly the same as 1,000 households. A large hyperscale facility can use up to 5 million gallons a day, equivalent to the daily needs of a town of 10,000 to 50,000 people. Google reported using more than 5 billion gallons across all its data centres in 2023, with 31% of those freshwater withdrawals coming from watersheds already rated as facing medium or high water scarcity.

And then there’s the indirect footprint. Because data centres consume vast amounts of electricity — US facilities used about 176 terawatt-hours in 2023 — and because electricity generation itself requires water, especially from thermoelectric power plants, the Environmental and Energy Study Institute estimates an additional indirect water consumption of around 211 billion gallons annually. Even an air-cooled data centre that uses no water on-site still drives water use through its power demand.

The Local Picture Is Very Different From the National One

The 0.2% national figure is one way to look at the issue. But researchers and environmental groups argue it can obscure what happens on the ground.

Loudoun County in Virginia — the world’s largest concentration of data centres — used around 1 billion gallons of mostly potable water in 2023 for cooling alone, about 2.75 million gallons per day. Across Northern Virginia more broadly, data centre water consumption rose by 63% between 2019 and 2023, reaching nearly 2 billion gallons annually. Nature Forward, an environmental organisation, estimates data centres now account for around 3% of total water consumption in the Potomac River Basin.

Texas tells an even sharper story. A study summarised by the Lincoln Institute of Land Policy projects that data centres in that state will use about 49 billion gallons of water in 2025, rising to up to 399 billion gallons by 2030 as AI-driven expansion accelerates.

One academic estimate, cited by the University of Georgia Cooperative Extension, suggests a single AI query uses about 16 ounces — roughly half a litre — of freshwater when accounting for cooling at the data centre handling the request. A United Nations-linked analysis warns that by 2030, AI data centres globally could consume around 9.3 trillion litres of water per year, enough to meet the annual needs of roughly 1.3 billion people.

Industry Points to Better Technology

Nvidia’s post isn’t wrong to highlight that the industry is changing. Globally, about 75% to 90% of data centres still rely primarily on water-based cooling. But newer approaches — direct-to-chip cooling, immersion cooling, and closed-loop systems — are gaining ground.

A closed-loop cooling system, which recirculates water rather than evaporating it, can cut freshwater use by up to around 70% compared with a conventional open-loop setup, according to the Brookings Institution. Major technology firms including Google and Microsoft have committed to using non-potable water sources and improving efficiency across their estates.

Sara Cotner, a water policy researcher at the Environmental and Energy Study Institute, said: “Data centres are becoming significant water users in many regions, and the national average can mask very real local pressures. Stronger transparency and reporting requirements are needed so communities can make informed decisions.”

Policy organisations including the Environmental and Energy Study Institute and Nature Forward have called for mandatory water use reporting from data centre operators, stronger planning guidance, and faster adoption of efficient cooling, chiefly in areas already under water stress.

What This Means for Kent Residents

Kent and Medway already face periodic water stress during dry summers, with the Environment Agency and Ofwat both flagging the South East as one of England’s most water-pressured regions. As demand for AI infrastructure drives data centre development across the UK, including in South East England, any large facilities proposed in or near Kent would face scrutiny from the Environment Agency, Ofwat, and local planning authorities over their water and energy demands. Residents living near any such sites could find themselves with a direct stake in planning applications that weigh jobs and investment against competition for local water supplies.