Part 6: Energy Reuse Factor (ERF)

Calculation formula:

also ERF=(ReuseEnergy)/(TotalEnergy)

Components:

E_reuse – Heat produced by the DC which is harvested and used outside of the DC

E_dc – Total DC building heat generation (energy consumption in kWh)

E_dc – Total DC energy consumption

Measurement Points:

Incoming building utility provider power meter – kWh.

Energy received and used based on either internal or external metering. 



Output from specialised BMS or intelligent DCIM software.

Actionable Insights:

ERF offers an operational view of the amount of energy flowing into a data centre which is subsequently ‘reused’ for non-data centre activities. This then allows the ability to monitor and ideally increase the amount of energy exhausted (and therefore being ‘wasted’), in the form of heat to be re-used in a way that can reduce (offset) the energy burden normally associated with other operations. Examples include, supply of heat to district heating systems, warming greenhouses, heating swimming pools etc. 

Note: Energy Reuse Effectiveness (ERE), which is not part of the standard, can be calculated from PUE multiplied by Energy Reuse Factor (ERF).

ERE = PUE × ERF, 1 ≤ ERE