Facebook’s new cooling system might make it easier to put data centers in hot places

As the data centers that run the computing world have become more powerful and sophisticated, just like their marketing executives, they produce a lot of hot air. Facebook says it has developed a new evaporative method for cooling its data centers that uses water to produce cool air for server rooms, which could allow it to put data centers in harsher climates around the world.

The new technology is called StatePoint Liquid Cooling, and it is an indirect evaporative cooling system, Facebook plans to announce Tuesday. The company believes the new technology will allow it to reduce water usage by existing indirect cooling systems by 20 percent in hot climates and by as much as 90 percent in cooler climates.

In most cases, Facebook uses a direct evaporative cooling system in its data centers. Direct evaporative cooling is a fancy way of describing sweat: the process by which the human body cools itself by releasing water that is cooled by the air. This is also the same idea behind the sidewalk misters you’ll find in Las Vegas or Palm Springs during the summer, and Facebook (and other data center operators) have been using mist as an efficient way to cool the air supply within data centers for several years.

This technique works best in places like Oregon’s high desert or Iowa’s plains, where Facebook has constructed a few of its data centers. But it doesn’t work as well in humid climates, where indirect cooling systems — in which water is cooled it passes through a special membrane, producing both cool water and cool air — are more effective.

To date, those indirect systems haven’t been as efficient at scale as data center operators would like, and that’s where the SPLC comes in. Electric power is a huge part of the cost overhead of running a modern data center, even if you’re not mining cryptocurrency.

The SPLC unit will sit on top of Facebook’s data centers and pass cool water down into the building alongside the server racks, where it will be turned into cool air that passes over the servers. The now-warm water is pumped back to the SPLC unit, where it is cooled again by the membrane, and the cycle begins again.

Facebook can choose between three different operating modes depending on the outside conditions. The system will still be at its most efficient in cooler locations, but the system will be efficient enough to be used in hot and humid climates with reasonable power consumption.

Unlike a lot of other data center hardware innovations it has developed over the past few years, Facebook is not donating the SPLC to the Open Compute Project as of this announcement. Nortek has patented this technology, which probably has something to do with it, but hopefully other data center operators will be able to license it at some point in order to bring fast computing power to underserved parts of the world.