ERE - STULZ answers

Energy Reuse Effectiveness (ERE) takes into account the alternative applications of energy lost in a data centre. Where PUE only looks at the consumption of energy, ERE goes further and looks at the alternative use of lost energy.

The ERE value is calculated based on the total energy minus the reused energy for the energy requirements of the computer systems and the IT equipment.

ERE = (1 - ERF) x PUE

Assessment: An ERE value of 0 means that 100% of the energy entering the data centre is reused in another place (outside the control volume of the data centre). Only energy that is reused outside the control volume of the data centre applies as recycled energy for the ERE. Any reuse of energy within the control volume is already taken into account by a lower PUE