Facebook, Lulea, Sweden
Located near the Arctic Circle, Facebook’s Lulea, Sweden, data center relies on cold ambient air to keep down temperatures of its servers. The air is treated with water vapor to give it the proper humidity and after cooling servers, some of the air is used to heat the offices. The facility runs entirely on hydroelectric power deemed so reliable that Facebook reduced the on-site backup supply. The company claims the ratio between power needed for the entire facility and the power consumed just by computing is 1.04:1 as compared to 3:1 for conventional data centers. Facebook’s custom servers can run safely at 85 degrees F, further saving on cooling needs.