Thermal design in the open compute datacenter

The advent of Web-based services and cloud computing has instigated an explosive growth in demand for datacenters. Traditionally, Internet companies would lease datacenter space and servers from vendors that often emphasize flexibility over efficiency. But as these companies grew larger, they sought to reduce acquisition and operation costs by building their own datacenters. Facebook reached this stage earlier in 2011 when it unveiled its first customized datacenter in Prineville, Oregon. In designing this datacenter, Facebook took a blank-slate approach where all aspects were rethought for maximum efficiency. Although the resulting datacenter is optimized for Facebook´s workload, it is general enough to be appeal to a wide variety of applications. This paper describes our choices and innovations in the thermal design of the datacenter building, which employs 100% outside-air economization. The efficiency of this design is manifest in an average infrastructure energy use reduction of 86% compared to leased space, and an overall energy use reduction of 29%. This reduction in turn translates to a power usage efficiency of 1.08, measured over the summer of 2011.