Google Looks To ‘Air Wands’ For Data Centre Cooling


Google’s patent application for a new cooling method for its servers gives a rare insight into the workings of its data centres

Google has submitted a patent application for a new process designed to cool the servers running in its enormous data centres.

Google is notoriously cagey about its data centre technology, yet remains keen to demonstrate its green credentials, either by investing in outside companies in order to produce renewable energy more cheaply than coal, or just going on record about the amount of carbon dioxide (0.2 grams) an average query generates.


What is known about Google’s huge server farms is that the company already builds its own servers and network switches. Now the search engine giant is seeking a patent on a cooling system dubbed the “air wand”, which is mounted across each server rack. The patent application can be located here, and a diagram of the system can be found here.

Essentially, it seems that the wands have in-built temperature sensors that can trigger localised cooling on the rack when required. There are vertical pipes of cold air running up the server rack, designed to deliver cold air to components in the server trays. This means that cooling is only applied to the area that needs it, thereby reducing power costs.

Cooling data centres and allowing them to run more efficiently is something of a holy grail in the data centre industry. Indeed, Google admits as much in its patent application.

“Power consumption is also, in effect, a double whammy,” said Google. “Not only must a data centre operator pay for electricity to operate its many computers, but the operator must also pay to cool the computers…”

Read Cooling Strategies for Ultra-High Density Racks and Blade Serversin the eWEEK Europe UK Resource Centre

“Thus, the cost of removing all of the heat can also be a major cost of operating large data centres,” it said. “That cost typically involves the use of even more energy, in the form of electricity and natural gas, to operate chillers, condensers, pumps, fans, cooling towers, and other related components.”

And it seems that Google’s designers have in mind a number of different implementations for its so-called ‘air wands’.

“In one implementation, a method of cooling electronic equipment is disclosed,” said Google. “The method includes circulating ambient air across a plurality of rack-mounted electronic devices, monitoring the temperature of air in or around a group of devices in the plurality of rack-mounted electronic devices, and providing substantially cooler-than-ambient air to the group of devices when a high cooling load is sensed for one or more of the rack-mounted electronic devices. The cooler-than-ambient air can be provided by a bank of air distribution wands arrayed upstream from the plurality of rack-mounted electronic devices.”

“In another implementation…The system includes one or more ambient air circulation fans arranged to circulate air over one or more rack mounted devices in a data centre, a sensor located near a rack mounted device to sense a load on the device, and a cooler-than-ambient air distributor near the device and configured to release cooling air over the device,” it said.

Author: Tom Jowitt
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