Microsoft's Project Natick team will spend the next year closely monitoring the data center's performance, and should everything go according to plan, it'll be operational for up to five years before it needs maintenance.
The company said on Wednesday that the Northern Isles data centre consists of a 12.2-metre-long white cylinder containing 864 servers - enough to store five million movies.
A cable, running under the sea, powers the centre and transports the data to the shore and the wider internet. Eventually, Microsoft would like to marry Project Natick to experimental ocean turbines that use wave energy to generate electricity, which could make these data centers entirely self sufficient.
Microsoft said: "More than half of the world's population lives within about 120 miles of the coast". By sinking undersea data centers near these coastal cities, Microsoft enables faster web surfing, video streaming, and game playing, while also bolstering cloud-based AI capabilities.
They are cooled with circulating sea water, which is piped through radiators attached to the back of the racks, and the internal operating environment is filled with dry nitrogen at one atmosphere of pressure.
The American tech giant describes such data centres as the backbone of the internet.
Spencer Fowers of Microsoft's special projects research group seals a logo onto Project Natick's Northern Isles datacenter in preparation for deployment.
There are two major goals with Microsoft's Project Natick.
The data centre's power can also be compared to as much as thousands of high-end desktop PCs.
It will not be possible to fix the computers if they fail, but the hope is that there will be a lower failure rate than on land.
This Davy Jones' data centre is the result of a year's worth of research into environmentally sustainable data storage technology that Redmond hopes could one day be ordered to size, rapidly deployed and left to operate at the bottom of the sea for years.
The cylinder was built in France by shipbuilding company Naval and then driven to the Orkney Islands, an archipelago of around 70 islands.