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Sip or guzzle? Here's how Google's data centers use water | Greenbiz

sip-or-guzzle?-here's-how-google's-data-centers-use-water-|-greenbiz

When Google declared in September 2021 its intention to “replenish 120 percent of the water we consume” by 2030, the giant technology company revealed few specifics about exactly how many gallons that pledge represents for individual facilities. That said, its water stewardship team offered plenty of details about the ideas and partnerships it will use to achieve “water positivity.”

On Monday, Google published some metrics it will use to benchmark that progress, focused predominantly on the data centers that drive its revenue, many of which rely on water to keep cool. Here’s the overall number to ponder: In 2021, Google’s global data centers consumed 4.3 billion gallons of water, or the amount of water it would take to irrigate 29 golf courses in the southwest U.S.

Considered another way, the average Google data center consumes 450,000 gallons of water on a daily basis. For those who love simple, everyday comparisons, that’s the amount of water required to grow cotton for 160 pairs of jeans, including the process of turning them into something in your closet. As far as U.S. data centers, Google’s facility in Council Bluffs, Iowa, withdrew the most water during 2021 — a whopping 1.1 billion gallons — a factor that Google executives tie to the location’s status as one of its largest campuses. 

“Servers are hot. We need to cool them,” observed Google CSO Kate Brandt when we chatted about the company’s evolving water stewardship strategy. That framework has three primary pillars, Brandt said: advancing responsible water use across its facilities (not just the data centers); supporting work on supply and quality issues in the watersheds impacted by its business; and using its technology to help other organizations navigate water-related issues. (An example is FloodHub, which uses satellites and artificial intelligence to predict river flooding up to one week in advance, allowing for better planning.)

Addressing the nexus of concerns related to water and electricity consumption — along with the associated impact on carbon dioxide emissions — is one of the biggest challenges faced by any big data center operator. In a blog about its new commitment, Brandt reports that water-cooled data centers use about 10 percent less energy than those using methods related to air cooling. Last year, the company estimated that using water cooling helped Google reduce the “energy-related carbon footprint” of its data centers by about 300,000 tons of CO2. 

Most of the overall amount of “operational” water that Google used in 2021 is related to these data centers; it withdrew 6.3 billion gallons during that fiscal year, according to its 2022 Environmental Report. Of that amount, 1.7 billion was discharged. As of 2017, Google was withdrawing about 3 billion gallons annually, so you can get a sense of why Google has focused on innovations related to “climate conscious” cooling.

That work will accelerate, according to Brandt and Ben Townsend, head of infrastructure and water strategy at Google. “We are working with local hydrologists … We also have to assess the energy landscape and the state of the grid… We are trying to optimize carbon-free energy and responsibly sourced water.” And this equation will balance very differently, based on location, Townsend said.

To get a sense of the possibilities, you can look to Google’s operation in Douglas County, Georgia, where the company is using reclaimed wastewater — of the 422 million gallons withdrawn at the site in 2021, just 13.2 million gallons were potable water. 

Although Townsend didn’t disclose the size of the investment, this was not a trivial undertaking. Google financed the development of a “sidestream facility” about five miles away from its data center. The system intercepts water from the Douglas County Water and Sewer Authority’s treatment plant that would otherwise be discharged into the Chattahoochee River — which holds status as a National Water Trail. That water is then sent to Google’s facility for use in the cooling process. Any water that isn’t evaporated is treated using effluent equipment at Google’s site, and then returned to the river. 

This approach near metro Atlanta represented somewhat of an unusual situation because many data centers are away from metropolitan centers, Townsend said. But by coordinating with the local municipality over the course of several years, the company was able to coordinate a reliable source of water, he said.

Using reclaimed water is a strategy in the Netherlands, where Google helped develop and fund an industrial water pipeline that reduces dependency on groundwater. The plant was built in collaboration with a subsidiary of the local water utility, North Water. An approach using desalination of seawater was considered, but discarded because of the intense requirements of that approach, according to local news coverage.

Townsend said that the use of reclaimed water is being evaluated for every data center location, but the company has no specific target for how much water it will recycle in the future. It is developing new systems that use a low-water alternative that reduces data center water use by up to 50 percent, but hasn’t yet shared details about when that approach will be available or whether it will be deployed first.

Google’s attention to water mirrors that of Meta, which has been reporting on its basic water consumption for at least seven years officially — and prioritizing ways to reduce it for at least a decade. Meta announced a goal to become “water positive” last fall by restoring water in the locations where its data center and facilities have an impact on consumption. According to its 2022 Sustainability Report, Meta withdrew about 5 million cubic meters in 2021, compared with about 3.7 cubic meters in 2020. It restored about 2.3 million cubic meters last year, slightly more than it did in 2020.

Microsoft has been less vocal about its water strategy, although it, too, has promised to replenish more water than it uses by 2030. Microsoft contracted to replenish about 45 percent of the water it withdrew in the 2021 fiscal year, or about 2 million cubic meters compared with its total consumption of 4.5 million cubic meters, according to its latest environmental report.

Compared with its rivals in the cloud computing space, Amazon has had relatively little to say about its water strategy although it, like Google, is prioritizing the reuse of water in its data centers. 

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