The demand for data centers is currently increasing due to modernization: more demand for IT facilities and networks. Data centers emit large amount of CO2 which obviously not healthy for the environment. Thus, the main concern is to reduce the energy consumption while keeping the energy use efficient as possible.

Efficiency of a data center has to be evaluated quantitatively in order to improve the efficiency of the data center and to minimize CO2 emission. At this time, comprehensive statistical data of the industry that indicates exact energy efficiency of data centers does not exist yet.

On the other hand, as a step towards CO2 reduction, JDCC use "PUE & DCiE"* recommended by The Green Grid (TGG) from U.S.A as indicators to measure the energy efficiency of a data center.

*Disclaimer: The concept of "PUE & DCiE" complies with measurement guidelines currently under review of standardization at ISO/IEC JTC 1/SC 39 to be added to the white paper compiled by TGG with regard to the agreement at the international conference held last February 2011.

Power Usage Effectiveness (PUE), as specified in ISO standard*:

Limitations*:

*Disclaimer:

The information is based on working draft text of ISO International Standard document which is still ammendable. It is subject to change without prior notice.