It is a large white steel tube, covered with heat exchangers, with its ends sealed by metal plates and large bolts. Inside is a single data center computing rack that was bathed in pressurized nitrogen to efficiently remove heat from computing chips while the system was tested on the ocean floor.
The idea for the underwater system came from a research paper written in 2014 by several Microsoft data center employees, including one with experience on a Navy submarine.
Norman A. Whitaker, the managing director for special projects at Microsoft Research and the former deputy director at the Pentagon’s Defense Advanced Research Projects Agency, or Darpa, said the underwater server concept was an example of what scientists at Darpa called “refactoring,” or completely rethinking the way something has traditionally been accomplished.
Even if putting a big computing tube underwater seems far-fetched, the project could lead to other innovations, he said. For example, the new undersea capsules are designed to be left in place without maintenance for as long as five years. That means the servers inside it have to be hardy enough to last that long without needing repairs.
That would be a stretch for most servers, but they will have to improve in order to operate in the underwater capsule — something the Microsoft engineers say they are working on.
They’re also rethinking the physical alignment of data centers. Right now, servers are put in racks so they can be maintained by humans. But when they do not need maintenance, many parts that are just there to aid human interaction can be removed, Mr. Whitaker said.
“The idea with refactoring is that it tickles a whole bunch of things at the same time,” he said.
In the first experiment, the Microsoft researchers said they studied the impact their computing containers might have on fragile underwater environments. They used acoustic sensors to determine if the spinning drives and fans inside the steel container could be heard in the surrounding water. What they found is that the clicking of the shrimp that swam next to the system drowned out any noise created by the container.
One aspect of the project that has the most obvious potential is the harvest of electricity from the movement of seawater. This could mean that no new energy is added to the ocean and, as a result, there is no overall heating, the researchers asserted. In their early experiment the Microsoft engineers said they had measured an “extremely” small amount of local heating of the capsule.
“We measured no heating of the marine environment beyond a few inches from the vessel,” Dr. Lee said.