Watt per Square Foot (WPSF)

A unit of power density. In a data center this is a bulk term that refers to the total load in a particular space divided by the total area of that space. This is a design parameter for total capacity of the cooling and power systems and is used in conjunction with point load (the amount of load in a small space such as a rack). In higher density data centers most operators refer to Kilo Watts per cabinet as measurement of capacity.