WATER POLITICS

For more than a year, Spain has been struggling with drought that has sent water levels in dams below historical averages, prompting local officials to tell residents not to water their gardens and to turn off taps at night to guarantee supply during the day. The situation is particularly hard for farmers. The central region of Castilla La Mancha, which produces a quarter of all Spanish grain, is expected to lose 80% to 90% of this year’s harvest, and water restrictions loom large.

Yet in Talavera de la Reina, a small city tucked among the region’s yellowing barley and wheat fields, Meta Platforms Inc. is planning to build a €1 billion ($1.1 billion) data center. Meta expects the facility to use about 665 million liters (176 million gallons) of water a year, and up to 195 liters per second during “peak water flow,” according to a technical report. Enthusiasm about the jobs the project is expected to create (1,000 in total, about 250 of which will be permanent) is now being weighed against heightened concerns over water.

“People don’t realize that ‘the cloud’ is real, that it is part of an ecosystem that consumes many resources,” says Aurora Gómez, a spokesperson for Tu Nube Seca Mi Río (“Your Cloud Dries Up My River” in Spanish), a group created to fight the construction. “People are not aware of the amount of water that goes into watching a kitten meme.”

We tend to think of the internet as immaterial, but websites exist in the real world as rows of servers that never turn off, filling data centers that need to be cooled to prevent technical failures. Operators such as Amazon, Google, Meta and Microsoft use a wide array of systems to do this; the most energy-efficient ones—such as cooling towers—typically evaporate water to chill the air circulating in the buildings.

With drought spreading around the globe, battles are emerging between data center operators and adjacent communities over local water supplies in places such as Chile, Uruguay and parts of the southwestern US. In the northern Netherlands, public outrage erupted last year when a local news outlet reported that a Microsoft Inc. data center complex was consuming more than four times as much water as the company had previously disclosed.

Some of the cooler, wetter hubs in northern Europe, such as Ireland and the Netherlands, have blocked the development of new data centers because of concerns about energy consumption, leading companies to start looking farther afield. Operators of hyperscale data centers, those with more than 5,000 servers, are migrating to places where water is plentiful, such as Norway, but also to drought-prone places like Italy and Spain where energy is cheaper—and where extreme heat is becoming the norm.

While data centers have faced scrutiny over their electricity use, little is known about their water consumption—including by tech companies themselves. A survey conducted last year by the Uptime Institute, a consulting firm, found that only 39% of data centers even tracked their water use, a 12 percentage-point drop from 2021. Tech companies in the past have refused to disclose information about individual centers’ energy and water consumption, claiming that such data was a trade secret.

Over the last couple of years, Google, Meta and Microsoft have started publishing their total water use across their operations, but they don’t break the number down by business unit nor use standardized metrics. Bluefield Research has estimated data centers use more than a billion liters of water per day, including water used in energy generation.

Governments are beginning to demand more information. Beginning in March 2024, the European Commission will require operators to report wide-ranging data about their energy and water use to the public. In the UK, the Thames Water utility is investigating the amount of water that data centers are using in London and may adjust its pricing model for water-intensive businesses depending on the findings.

Global Data Center Water Consumption

In gallons per day

Identifying which water-intensive clients are data centers hasn’t been easy, says John Hernon, who’s heading up the probe. Operators often use shell companies to apply for planning permissions, and a data center can look like any large warehouse or factory from the outside.

Arman Shehabi, a researcher at the Lawrence Berkeley National Laboratory in California best known for a landmark paper on energy consumption at data centers, thinks the facilities could contribute to scarcity as droughts become longer and more intense. Part of the problem, he says, is that data center operators “are generally the last ones to the table to ask,” straining the system by asking for access to scarce water after agricultural interests and local communities have already come up with a plan. “Everybody is going to feel that,” he says.

Companies say data centers are getting more energy-efficient, but the increase in overall demand for computing power is outpacing such gains. The race to build large language models used in generative AI has created a surge in demand for more powerful processors. The specialized chips required for AI—broadly known as accelerators—emit so much more heat than general-purpose chips do that data center operators are having to rethink their cooling systems entirely, says Colm Shorten, a data center sustainability expert at real estate investment firm JLL.

Shaolei Ren, associate professor of electrical and computer engineering at University of California, Riverside, has conducted research estimating that training GPT-3 in Microsoft’s US data centers directly consumed 700,000 liters of water in about a month—not including the indirect water use associated with electricity generation. The team has also calculated that every short conversation of 20 to 50 questions and answers with ChatGPT represents about 500 milliliters of water.

“Microsoft is investing in research to make large systems more sustainable and efficient, in both training and application,” said a Microsoft spokesperson in an emailed statement. “Climate change is a real and urgent challenge, with increasingly severe impact on our businesses, our communities, and the ecosystems that sustain them.” OpenAI did not respond to requests for comment.

Shorten says that over time data centers will need to radically change the way they dissipate heat. The gold standard, he says, is a process called immersive cooling, in which servers are bathed in a special fluid that transfers heat from the chips. For now, operators are likely to opt for a hybrid model, wherein a high-performance section of the data center will be liquid-cooled while the rest will continue to use air conditioning, he says.

Amazon Web Services, Google and Microsoft have all made water stewardship pledges, promising to use more nonpotable and recycled water and to replenish more water than they consume operationally by 2030. This is the equivalent to offsetting carbon by planting trees—something that looks good on paper but may not directly benefit the communities affected by data centers, because water may be replenished only in places where it’s easy to do so.

In Spain, Meta has pledged to “restore more volume of water than is consumed at the facility, through hydrological restoration projects,” but it hasn’t yet determined whether water restoration efforts will affect Talavera. It says it recycles water used in its facilities and has reduced the controlled humidity level in data halls where it uses direct evaporative cooling, cutting water consumption by 10% to 65% across those facilities.

As authorities experiment with provisional measures such as covering one of the town’s central streets with a canopy of umbrellas to protect locals from the sun, Gómez from Tu Nube Seca Mi Río is skeptical that tech’s promises to help will have any positive effect on Talavera. The water replenishment plans fulfill two objectives, she said: “to look good in the eyes of the general public, and to win over a local environmental group.”