An underwater data centre could start operating off the west coast of the US before the end of 2022. The project is an attempt to show the viability of using the ocean to provide cooling, which normally accounts for a large portion of data centre energy use.
“By placing the data centres subsea, we eliminate the electrically driven cooling which is 40 per cent of the power consumption,” says , co-founder of , the company behind the initiative. “If you eradicate 40 per cent of the power consumption, you do the same to the carbon emissions.”
Subsea Cloud has designed a modular data centre consisting of steel pods the size of a shipping container. Each pod can hold 16 standard server racks filled with about 800 computer servers. The modular design means that it could be scaled up to hundreds of pods.
Advertisement
Unlike most land-based data centres, the pod’s servers are directly immersed in a special fluid similar to mineral oil that doesn’t conduct electricity. Excess server heat passes to the fluid, through the pod’s walls and then into the surrounding ocean.
Deploying a pod involves the help of a surface ship equipped with two remotely operated vehicles and a subsea digging machine. Servers typically need replacing every three to five years, which would be done by periodically sending the ship to swap out pods.
The company has previously tested a prototype pod with functioning servers at an ocean depth of 3000 metres. Pods don’t necessarily need to be installed at such depths, but their capability to survive under such conditions was meant to show the soundness of the design and engineering.
Now, Subsea Cloud plans to build its first commercial data centre at Port Angeles in Washington state at a depth of 9 metres, starting with one pod within sight of the port and potentially scaling up to 100 pods. It will be able to perform all the usual functions of a data centre, such as storage and computational processing.
The company says it could deploy 1 megawatt-worth of data centre capacity underwater for about $700,000, compared with the usual $6 million price tag for land-based data centres.
The excess data centre heat could raise the water temperature within the immediate vicinity, says  at the University of St. Thomas in Minnesota. However, it would have a “negligible effect on ocean warming” and could actually help reduce global warming because of the reduced power requirements.
The start-up is not alone in pursuing this idea.  plans to build an underwater data centre consisting of 100 modules near China’s Hainan Island, after previously testing a single module holding four server racks in 2021.
Microsoft has also investigated the idea with , though it hasn’t pursued its “Project Natick” further. “We will continue to use Project Natick as a research platform to explore, test and validate new concepts around data centre reliability and sustainability, for example with liquid immersion,” says , a director at Microsoft Research.
Subsea Cloud has lined up two more projects in the Gulf of Mexico and in the North Sea with planned operating depths of about 213 metres. It plans to eventually power the underwater data centres’ servers using offshore wind turbines.
