Microsoft’s underwater Northern Isles data center has risen again from the ocean depth, the company announced on Monday, and it is remarkably intact other than being covered in sea scum.
The data center—which Microsoft sunk under 117 feet of water off the coast of Scotland’s Orkney Islands in 2018—resembles a large, airtight fuel tank. After two years on the seafloor, it is now blanketed in algae, barnacles, and cantaloupe-sized sea anemones. But Microsoft Special Projects researcher Spencer Fowers said in the announcement the company was “pretty impressed” at the lack of “hardened marine growth.”
Inside, 864 servers with a collective 27.6 petabytes of storage and cooling infrastructure braved the elements in an atmosphere of inert gas—Microsoft noted that conditions European Marine Energy Centre test site can include nine mile per hour tidal currents and 60-foot waves during storms. In fact, Microsoft claimed the equipment fared better than land-based systems. Project Natick leader Ben Cutler said in the blog post that Northern Isles experienced failure rates just one-eighth what would have been expected in a traditional data center and that it ran “really well” on the region’s energy grid, which is 100 percent wind and solar.
That vindicates the hypothesis the seafloor is preferable for server farms to topside environments where gear can be damaged by corrosion from oxygen and humidity, constant temperature changes, and physical movement during maintenance. Putting data centers underwater may also enable closer placement to customers and obviously makes cooling far easier, and Microsoft has previously suggested they could be powered by tidal generators. The units are also portable and could be easily scaled into larger operations.
One obvious issue is that repairs in situ are impossible, though Microsoft wrote in the blog post that servers at lights-out datacenters are already replaced twice a decade. The company hopes the increased reliability of underwater servers means “the few that fail early are simply taken offline.”
The Verdict reported in 2018 that the possible environmental impact of underwater data centers is unclear; one unit may have a negligible impact on local temperature, but masses of them might have noticeable effects on sealife.
“Whilst there may be substantial benefits for companies such as Microsoft in transferring data storage systems offshore, the effects of any structure placed in the marine environment, especially one that generates substantial heat locally, would have to be investigated,” University of Portsmouth marine ecologist Gordon Watson told the Verdict. Watson added that any site would need to be assessed for environmental impact and that “It is not as easy (at least in countries where they have advanced marine planning legislation) as just sticking something on the seabed and retrieving it five years later.”
There’s also the problem of diminishing returns. Leeds Beckett University School of Computing, Creative Technologies and Engineering dean Colin Pattinson told Wired in 2018 that while underwater data centers are “worth a try,” efficiency gains for reducing power needs are decreasing over time.
“Effectively what we’re trying to do now is squeeze yet more savings out of the same basic tech,” Pattinson told Wired. “We might reduce the rate of the increase but there will still be an increase in the energy demands that data centres create because of the volumes of data we’re producing.”
The next phase of the Project Natick will be demonstrating ease of removal and recycling.
“We are now at the point of trying to harness what we have done as opposed to feeling the need to go and prove out some more,” Cutler said in the announcement. “We have done what we need to do. Natick is a key building block for the company to use if it is appropriate.”