Why did Microsoft just sink a small data centre off the coast of a Scottish island?

The Northern Isles data centre from Project Natick is Microsoft’s latest experiment in keeping data centres cool and increasing energy efficiency.

This week, Microsoft’s ambitious Project Natick team celebrated the submersion of a data centre 117ft to the Scottish seabed.

Marking phase two of what Microsoft CEO Satya Nadella calls a “relevant moonshot”, Project Natick sunk a data centre the size of a standard shipping container off the coast of the Orkney archipelago to see if the concept proves logistically, environmentally and economically practical.

What they learn from this endeavour could contribute significantly to how data centres of the future are built and deployed.

The Northern Isles data centre

The Project Natick submersible is miniature, as data centres go. Dubbed the Northern Isles data centre, the structure houses 12 racks of 864 servers with FPGA acceleration and 27.6 petabytes of disk. Basically, enough to store about 5m movies.

The white cylindrical vessel requires 240KW of power, which will be entirely sourced from wind, solar, tidal and wave energy produced locally, both onshore and off.

All going well, the Northern Isles data centre will remain self-sufficient on the seafloor for the next five years. If any component breaks down in that time, the project will have to continue without as surfacing for repairs will be too costly and cumbersome.

The cylinder was built in France by Naval Group, a shipbuilding company with experience in building submarines and working with marine energy technologies. “At the first look, we thought there is a big gap between data centres and submarines, but in fact they have a lot of synergies,” said Eric Papin, director of innovation for Naval Group.

In fact, the underwater data centre uses an adapted submarine heat-exchange process for cooling. The system pipes seawater directly through the radiators on the back of each of the 12 server racks and back out into the ocean.

The issue has been raised that this method of using the marine environment to cool a data centre will also result in warming the surrounding water, to the detriment of the ecosystem. Project Natick lead Ben Cutler dismissed these concerns, claiming that “the water just metres downstream would get a few thousandths of a degree warmer at most”. According to the research team’s findings from phase one of the project, water from the data centre rapidly mixes and dissipates in the surrounding currents.

Why Orkney?

In a word, energy.

The European Marine Energy Centre (EMEC) is based here, and producing renewable tidal and wave energy in abundance. Managing director Neil Kermode told the BBC: “We’ve produced more [renewable energy] than we need since 2012.”

Deployment of the Northern Isles data centre off the coast of Orkney island, Scotland. Image: Scott Eklund/Red Box Pictures

The EMEC helped Project Natick link the Northern Isles data centre to the shore via an undersea cable.

Part of the rationale behind the project is that so much of the world’s population – and, therefore, its data end-users – live within 200km of the coast. (Microsoft says as much as 50pc.)

Data centres are often found dotted around major cities, but offshore data centres could prove a viable and speedy option for data processing and transfer if all conditions of cooling, efficient energy usage and self-sufficiency underwater can be met.

Not Microsoft’s first underwater rodeo

This is not the first experiment in underwater data centres from Project Natick.

In 2015, its first prototype was booted into operation 1km off the California coast, running from August to December. The steel-encased vessel was fitted out with environmental sensors and christened Leona Philpot after a character in the popular Xbox video game, Halo.

Leona Philpot was then shipped back to Microsoft’s Redmond HQ for analysis, barnacles and all. The findings from this trial helped formulate plans for the Scottish experiment.

‘At first look, we thought there is a big gap between data centres and submarines. In fact, they have a lot of synergies’
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Assembly of the Northern Isles data centre took place at Naval Group’s facility in Brest, France. Image: Frank Betermin

Data centres of the future

Data centres are forecast to consume up to one-fifth of the world’s electricity by 2025. Even though processing power is improving alongside the expansion of data needs, the fact is that data centres need energy to keep the digital world running at pace. New developments such as cryptocurrency only exasperate the issue, with recent research showing that bitcoin mining could consume as much electricity in a year as all of Ireland.

The offshoot of all that energy is heat. Keeping data centres cool is top of the agenda – and it’s why they can turn up in strange places, such as underground bunkers and the Arctic Circle.

Also, as the energy needs of data centres increase, it’s prudent to do all that’s possible to ensure that energy comes from renewable sources and the structures strive for zero emissions.

As if all that wasn’t enough reason to trial underwater data centres, there’s also the low-latency convenience of locating data centres offshore of populous areas and the fast deployment of the Project Natick vessels. On land, data centres can take years to deployment – Project Natick’s took less than 90 days from factory ship to operation.

Five years from now, we’ll have the data on how the Northern Isles centre survived its underwater adventure. If it’s a success, Microsoft will move toward building bigger structures combining vessels such as the one in this experiment in sets of five for fast, efficient deployment of future connectivity.