Microsoft has successfully completed Phase 2 of the Project Natick program, bringing its experimental underwater data center to the surface. He worked underwater for two years, setting a kind of record. During the first stage, the small and simple module was lowered for only three months, in the warm waters of California, and in the second stage, the large and heavy block was drowned in the cold North Sea near the Orkney Islands in Scotland.
The underwater data center was submerged to a depth of 36 meters, in a place with a strong enough current so that water flows constantly flow through the external radiators of the case and carry away excess heat. Inside a steel tank 12 m long and 3 m in diameter, 12 server racks were placed, on which 864 servers were mounted. Oxygen was evacuated from the tank and the entire interior was filled with dry nitrogen.
The results of the mission are as follows: in two years of operation, the number of server failures in an underwater data center was eight times less than in a similar ground-based facility. Several servers and some of the cable equipment failed, they were sent to Microsoft laboratories to study the causes of the breakdowns. But most importantly, the concept of an underwater data center has fully justified itself.
As the authors of the project noted, passive cooling with seawater was far from a priority goal of the study. It was much more important to create a stable and reliable environment, where there are no changes in temperature and humidity, where oxygen oxidation of the equipment does not occur, and finally, where the human factor is excluded - no one walks between the racks and does not touch them. The compact subsea module fits perfectly and field tests have proven it. This opens up great prospects for the creation of efficient and cost-effective data centers that will be under water without taking up valuable surface space.