Microsoft has retrieved an underwater data centre from Scottish waters after two years of providing cloud services from the bottom of the ocean.
The 40-foot cylinder, which descended into waters off the coast of Orkney in spring 2018, is powered by tidal turbines and wave energy converters.
Marine specialists took just a day to retrieve the data centre, which was coated in algae, barnacles and sea anemones from the seafloor after being deployed 117 feet deep – without affecting its operations.
Throughout its test period, 'Project Natick', as it's known by the US firm, had a lower failure rate than a conventional data centres and reduced energy consumption.
The on-board servers – the physical electronic equipment that process data storage – were protected from the surrounding water, supporting customers of its Azure cloud services.
Microsoft Azure is now looking to serve customers who need to deploy and operate data centres anywhere in the world.
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Pictured, the 40-foot cylinder being retrieved after spending two years underwater powered by tidal turbines and wave energy converters underwater
The data centre was originally deployed at the European Marine Energy Centre, a test site for tidal turbines and wave energy converters, and stationed in waters, based in the Orkney Islands.
Microsoft says the underwater data centre is as powerful as 'several thousand high end consumer PCs' and has enough storage for about 5 million movies.
The US firm has been testing the feasibility of keeping data centres underwater in the long term, which helps to keep low and consistent temperatures.
Project Natick has proved the concept of underwater data centres is 'logistically, environmentally and economically practical', it says.
'We had this theory that if the data centre was in a really stable environment with all the oxygen taken out and no one walking around bumping things then we would see better reliability,' said Spencer Fowers, principal researcher on Project Natick.
'We have got some good data on reliability and we have proven we can do this whole deployment process.
'We have been able to run really well on what most land-based data centers consider an unreliable grid.'
The data centre was originally deployed at the European Marine Energy Centre, a test site for tidal turbines and wave energy converters
The Project Natick team power washes the Northern Isles underwater datacenter, which was retrieved from the seafloor off the Orkney Islands in Scotland
When the Project Natick cylinder was hauled off the seabed around half a mile offshore, just eight out of the 855 servers on board had failed.
Overall, the underwater data centre had one-eighth of the failure rate of a similar data centre on land.
The container was gleaming white when deployed two years ago, but upon retrieval it had a thin coat of algae and barnacles.
It was power-washed before being transported to Orkney for tests to be carried out on it and samples sent for analysis at Microsoft headquarters in Redmond, Washington, US.
'We were pretty impressed with how clean it was, actually,' said Fowers.
'It did not have a lot of hardened marine growth on it – it was mostly sea scum.'
Once analysis is finished, the steel pressure vessel, heat exchangers, servers, and all other components will be recycled.
Microsoft researchers believe a sealed container on the ocean floor could provide ways to improve the overall reliability of data processing.
Lessons learned from Project Natick are already informing conversations about how to make datacenters use energy more sustainably, Microsoft said
Staff remove 12 racks of servers and related cooling system infrastructure from the underwater data centre
On land, corrosion from oxygen and humidity, temperature fluctuations and bumps and jostles from people