Alcance
This document specifies the cooling efficiency ratio (CER) as a key performance indicator (KPI) for quantifying the efficient use of energy to control the temperature of spaces within a data centre (DC).This document:a) defines the CER of a DC;b) describes the relationship of this KPI to a DC’s infrastructure, information technology equipment and information technology operations;c) defines the measurement, the calculation and the reporting of the parameter; andd) provides information on the correct interpretation of the CER.Annex A describes the correlation of the CER and other KPIs.Annex B provides examples of the usage of the CER.Annex C introduces the parameters that affect the CER.Annex D describes requirements and recommendations for derivatives of KPIs associated with the CER.This document is not applicable to cooling systems that are not powered by electricity (e.g. heat-driven absorption chillers).