Trade journalists from DataCenterKnowledge were recently allowed to tour Facebook's new data center in Prineville, Oregon, and came back with a pair of revealing videos. One video covers the inside of the facility's server room, including a look at custom servers, racks and UPS units that were created for the site. Another video goes inside the facility's "penthouse" cooling system, which reportedly "uses the upper floor of the building as a large cooling plenum with multiple chambers for cooling, filtering and directing the fresh air used to cool the data center."
This diagram from the Open Compute Project provides a building-level view of the penthouse cooling design implemented at the new site, showing the hot air plenum for server waste heat and the server rooms. The top half of the facility is used to manage the entire cooling supply. Cool air enters the server room from overhead, which eliminates the need to use air pressure to force cool air up through a raised floor.
