According to the state’s official website, California is currently in the midst of one of the most severe droughts it has ever faced. This led officials to declare a state of emergency and issue a number of rules and regulations for water usage. Oftentimes, these stipulations focused on water consumption by state residents and agricultural organizations. However, the spotlight has recently shifted to increasingly focus on data centers.
Data center water consumption
Earlier this year, The Wall Street Journal reported on water usage in the data center industry, noting that even a mid-size facility consumes as much as 130 million gallons of water annually. This is the same amount of water that would be used for three hospital buildings, or two 18-hole golf courses on a yearly basis.
However, Keith Klesner, Ryan Orr and Matt Stansberry of the Uptime Institute wrote for TechTarget that The Wall Street Journal’s statistics may not be as telling as they seem.
“According to the Uptime Institute’s survey data, an average data center deployment is about 1 MW, and would consume approximately 7 to 8 million of gallons of water annually,” Klesner, Orr and Stansberry noted. “That’s still … five holes of golf, or a little less than a third of a hospital.”
As these authors point out, while some estimates make the issue seem worse that it actually is, this does not mean the data center industry is not in need of more efficient solutions for its water consumption.
Reducing heat with water
Although water is utilized for other purposes within data centers, the main source of consumption is for heat reduction. Many of today’s facilities utilize chiller systems to eliminate the considerable heat created by servers and other computing equipment. Most of these systems rely on cooled water that runs through a coil, conditioning the air before it is sent to the server rooms. The water is continually circulated through the system for cooling.
Fortune pointed out that nowadays, a number of facilities are using gray or recycled water for cooling. So where, exactly, is water potentially being wasted?
According to Klesner, Orr and Stansberry, the cooling tower that is part of the water-cooled chiller system is the “main culprit for water consumption.” This is because this large unit can lose 1-2 percent of the millions of gallons utilized for cooling yearly through evaporation and drift. Water being cooled in this apparatus can be blown away in a fine mist by the internal fan. And while 2 percent may not seem like a lot, this can quickly add up.
“That comes out to about 6.7 million gallons of water consumed annually,” Klesner, Orr and Stansberry wrote. “An additional 1.3 million gallons of water per year are lost in blowdown, or the replacement cycle. As the condenser water is repeatedly evaporated and exposed to the atmosphere, it picks up minerals, dust and other contaminants. That water must be treated, and/or dumped out at regular intervals. In total, a 1 MW data center using traditional cooling methods uses about 8 million gallons of water per year.”
Why California’s data center industry poses a problem
While this may not be as big of an issue in other parts of the country where water is less of a scarce resource, California, in particular, poses a considerable problem. Not only is the area in a state of emergency due to the drought, it also has a significant number of data center facilities. According to Fortune, California boasts over 800 data centers, more than any other state in the country. And despite these water consumption issues, the state still offers an attractive location for the tech industry due to its proximity to a number of data center service-dependent markets.
“Tech companies will continue to be torn by the need to put data centers close to end users – the longer the distance, the more the delay or latency in communications,” Fortune contributor Bob Darrow wrote. “That may not matter for some applications, but for split-second stock trades or even for streaming media, that can make a difference.”
Alternative cooling methods
In recent years, there has been a significant push throughout the data center industry for more efficient services. While this has primarily focuses on energy usage in the past, efforts have also extended to include water consumption.
Currently, several operators – especially those with facilities in California – have been examining and deploying alternative cooling methods that help reduce the amount of water consumed. These include chiller-less systems that incorporate the use of evaporative cooling as well as economizers that leverage outdoor air. These types of cooling solutions have been seen much more often, particularly with new construction.
“In Uptime Institute’s experience certifying data centers around the globe, about one-third of new builds use some form of cooling system that does not utilize traditional chilled water and cooling tower combinations,” wrote Klesner, Orr and Stansberry.
California’s drought is having quite the impact on the state’s data center industry. New builds are deploying more efficient cooling systems, and existing facility operators are examining ways to reduce water consumption and replace older cooling strategies. Water usage will become a higher priority for data center service providers, particularly those with a focus on sustainable practices.