Google recently filed a patent for a “water-based data center” that uses the ocean to provide power and cooling. The patent confirms Google’s development of a container-based data center, and Google says the data center containers could be stacked two or more high, so that each data barge could hold “12 or more” containers. The patent documents describe a cooling system based on sea-powered pumps and seawater-to-freshwater heat exchangers.

A sketch from Google’s patent application for a floating data center. (Photo: Google)

The floating data centers would be located 3 to 7 miles from shore, in 50 to 70 meters of water. If successful, this approach could be used to build 40 megawatt data centers that don’t require real estate, aren’t subject to property taxes and may not be subject to the same laws as data centers on land. Google said it would use signaling mechanisms such as strobing lights, flags, and horns to alert ships of the location of its data centers. In contrast, Google’s competitor, IDS (International Data Security), plans to build up to 50 data centers on de-commissioned cargo ships moored at piers in major cities.

The Google design incorporates the Pelamis Wave Energy Converter units, which use the motion of ocean surface waves to create electricity and can be combined to form “wave farms.” Diagrams included with Google’s patent application indicate the company plans to combine 40 or more Pelamis units to produce 40 megawatts of power.

Google previously was granted a patent for a portable data center inside a shipping container, which the company began developing in 2003, well before competitors began unveiling products based on the “data center in a box” concept.

Google has also announced earlier this year that it would partner with five other companies in building an undersea communications cable across the Pacific to provide high-speed connectivity to new Google data centers in Asia.

• Read more: Google Planning Offshore Data Barges, Datacenterknowledge.com (9/6/08)
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• Saving Energy and Money By Reusing Waste Heat From Data Centers
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