An Approach to Calculating and Defining Overall Data Center Energy Efficiency
The definition of data center efficiency in terms of the facility elements is well established. The universally adopted metric, Power Usage Effectiveness (PUE)[1] has several categories.
There are two important issues associated with PUE.
1. PUE is not intended to take into account the energy efficiency of the IT equipment within the data center.
2. There are emerging trends toward locating some power and cooling functions that are normally part of the facility within the IT equipment. This obscures the demarcation between the facility and IT and can skew PUE results.
In this paper a suggested framework for defining and calculating IT energy efficiency in terms of compute, network and storage in conjunction with PUE is discussed. The combination of these metrics results in a new metric for the overall data center efficiency.