What metrics are used to measure the energy efficiency of a data center?

For a data center to be energy efficient, what could be the possible metrics to measure its efficiency.

As shared by others as well, most widely used metric to measure the energy efficiency of a data center is PUE which stands for Power Usage Effectiveness.

It can be determined by using following formula: PUE = Total Facility Power / IT Equipment Power

The power measured at the utility meter is Total Facility Power and all the actual load of IT equipment such as workstations, servers, storage, switches, printers and other service delivery equipment constitutes IT Equipment Power. I hope now you can calculate your data center efficiency yourself with few known quantities.

PUE can be measured on the scale from 1 to 4. 1 being very efficient and 4 being very inefficient. So, you may want to limit your Total facility Power and increase your IT Equipment Power.

For instance, C7 Data Center's new unit at Utah has a total facility power of 10MW and IT equipment power of 8.34MW, that limits the PUE to 1.2. That is quite good enough for a big data center.

For more information about this unit, check: http://www.c7.com