Google cools data center without chillers
Google's new data center in Belgium uses outdoor air for free cooling with no chillers.
Google has begun operating a data center that has no chillers to support its cooling systems, a strategy that will improve its energy efficiency while making local weather forecasting a larger factor in its data center management, according to Data Center Knowledge. [http://www.datacenterknowledge.com/archives/2009/07/15/googles-chiller-less-data-center/] The data center, near St. Ghislain, Belgium, will use outdoor air for cooling almost all year, and will shift the computing load to other data centers on the few days that ambient temperatures are too warm.
The climate in Belgium will support free outdoor-air cooling almost year-round, according to Google engineers, with temperatures rising above the acceptable range for free cooling about 7 days/yr on average. The average temperature in Brussels during summer reaches 66 to 71 F, while Google maintains its data centers at temperatures above 80 F. Most data centers that use free cooling switch to chillers when the days get too warm. Belgium's favorable climate, along with the ability to quickly shift computing loads, will allow the Google data center to operate with no chillers at all.
Google's Vijay Gill hinted that the company has developed automated tools to manage data center heat loads and quickly redistribute workloads during thermal events. The ability to seamlessly shift workloads between data centers creates intriguing long-term energy management possibilities, including a "follow the moon" strategy which takes advantage of lower costs for power and cooling during overnight hours. In this scenario, virtualized workloads are shifted across data centers in different time zones to capture savings from off-peak utility rates.