WUE - STULZ answers

Water Usage effectiveness (WUE) is the ratio of the data centre’s annual water consumption in litres to the energy consumption of the IT equipment in kilowatt-hours (kWh). WUE is used as a data centre’s sustainability meter. This sustainability meter was created by The Green Grid  in 2011 to measure the amount of water used by data centres to cool their IT equipment. The WUE takes into account water used to cool, regulate humidity and produce electricity locally.

What use is the WUE to you?
A data centre’s manager can use a water consumption measurement to ascertain the impact of water consumption on the local electricity grid. By using the WUE in combination with the effectiveness of power consumption and carbon usage, an organisation can reduce energy consumption and thus the amount of water and electricity needed to operate the data centre efficiently.

Calculating WUE
To calculate WUE, the data centre’s manager divides the location’s annual water consumption in litres by the energy consumption of the IT equipment in kilowatt-hours (kWh).

WUE= Annual water usage/P_IT

The water consumption includes the water used to cool and possibly regulate humidity, although the latter is not necessary at the correct settings. Power for IT equipment includes all the power consumed by hardware used for the day-to-day operation of the data centre. STULZ can provide advice on complex WUE calculations. Please feel free to contact  us in this respect.