A mysterious barge has materialized near San Francisco, and naturally, has been generating a lot of speculation. Moored off of the Treasure Island pier, the massive barge is reported to be part of a new Google project to create floating data centers. Other sources are saying that it is actually going to be some sort of a maritime office, or even a mobile store from which to peddle Google Glass. Paradoxically, the more we learn about this project, the less sure we seem to be about its exact mission.

Research by CNET indicates that a similar project near Portland has begun to take shape as well. A company called By and Large appears to be the owner of both barges, as well as the tenant of a huge hangar on Treasure Island. Google’s prints have been found all over Treasure Island, along with several links to By and Large. A large yacht, which appears to be Larry Page’s personal watercraft — “The Senses” — has also been seen docked at the pier.

Treasure Island is an artificial island owned by the US Navy, and subleased by San Francisco. The barge located there is some 250 feet (76 meters) long, 72 feet (21 meters) wide and 16 feet (4.8 meters) deep. The mysterious part is what is taking shape on top of the barge — a four-story assemblage of what appears to be some kind of shipping or cargo containers. The speculation that the intended use is as a data center has been fueled by Google’s own 2009 patent for a “Water-based data Center.”

Claim 1 of the patent calls for crane-removable building blocks which could be configured rapidly according to need. There are also provisions in the patent for Pelamis-like wave power generation systems, and for water cooling the servers in the data center. In theory, a floating data center could be towed into place to support emergency or even military operations anywhere in the world. It could also be towed into cool waters where cooling a massive server farm might be readily accomplished without huge air-conditioning expense. (See: Microsoft now has one million servers – less than Google, but more than Amazon.)

As for how a floating data center would be connected to the internet at large, we’re not entirely sure. A wireless link would be possible, but probably lacking in bandwidth. Unless the barge is very static and heavily anchored (which somewhat defeats the point of a floating data center), a high-bandwidth submarine cable wouldn’t be possible.

Other reports have suggested that the real purpose of the floating office is to distribute Google Glass. The traveling gypsy sales model may be a new one for Google, but it might have some practical appeal. For reasons unkown, construction on the barge appears to have come to a halt in recent weeks. Reports have suggested that Google has run afoul of authorities in securing the proper permits to park the barge on the waterfront. One permit stipulation appears to be that activity taking place on the barge must not be possible to otherwise do on land.

In recent years, Google has been involved with several large projects, such as building its own airport, that would seem to skirt the borders of .com and .gov, and it may be likely that Google will be able to quickly iron things out. It may require however, that Google declare a specific purpose for its new operation — and then we’d finally know for sure what the barge will be used for.

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