Microsoft has sunk an experimental data center off the coast of Orkney, Scotland, in bid to boost energy efficiency, BBC reports. Packed with enough computers to store five mn films, the submerged waterproof tube could sit on the seafloor for up to five years. The experiment hopes to demonstrate how storing data underwater can help make data centers more energy efficient while providing a cheap solution for cooling. “On land, we might use 15% or 20% or even more of the energy for cooling. It’s almost zero when we’re in the water,” says Microsoft Researcher Ben Cutler. Using renewable wind and coastal energy through a cable on the ocean floor, the cylinder will be connected to the wider internet.