3 Steps to Calculate Total Enterprise IT Energy Consumption Using DCIM

Overview

Scope covers not only on-premise data centres but also distributed edge sites, end-user devices and outsourced cloud and colocation capacity. The one recommended metric is total energy consumption (kWh/MWh). It includes grid electricity and onsite generation (generators, solar, wind), plus imported natural gas, steam or chilled water where applicable.

The three steps are: assess coverage, pick data sources and fill metering gaps, then aggregate in DCIM. Distributed IT sites are defined as fewer than 10 IT racks plus non-racked IT equipment. Recommended minimum sources are a utility meter or invoices for on-premise data centres, the built-in UPS power meter for edge sites, power rating x time for end-user devices, and vendor reports or a tenant portal for outsourced capacity.

Two estimation rules cover missing meters: for unmetered devices use 60% of the manufacturer's power rating times assumed hours of use; where upstream power and cooling are shared or unmeasured, multiply IT energy at the UPS output by the site PUE. Power dependencies must be modelled correctly in DCIM or pairs such as a UPS and its downstream rack PDU get double counted. An appendix converts energy to location-based Scope 2 emissions: energy x emission factor (tCO2/MWh). Beginners are told to use the location-based method with local, or else national or regional, factors. The GHG Protocol Scope 2 Guidance and ISO/IEC 30134-2 are the related references.

Key points

1. Total energy: grid electricity, onsite generation and, where applicable, imported gas, steam or chilled water.
2. Unmetered devices: 60% of manufacturer rating x assumed hours of use.
3. Shared or unmeasured infrastructure: UPS-output IT energy x site PUE.
4. Distributed IT site: fewer than 10 IT racks plus non-racked equipment.
5. Minimum sources: meter/invoices on-premise, UPS meter at edge, power x time for end-user devices, vendor report or portal for outsourced.
6. DCIM power dependencies (a UPS and its rack PDU) must be defined to avoid double counting.
7. Emissions = energy x factor (tCO2/MWh); location-based method for beginners.

Using it in design

• Model each meter point as a power-tree node with an aggregate flag so roll-ups never sum a parent and its child.
• Provide an estimate mode when facility meters are absent: IT kWh at UPS output x design PUE.
• Add an editable 60%-of-nameplate default for unmetered devices.
• Add a per-site emission factor field (tCO2/MWh) and flag sites with no metering point at the UPS output.

Who should read it

Staff building enterprise IT energy and emissions reporting, and DCIM implementers.

Related standards

• GHG Protocol Scope 2 Guidance
• ISO/IEC 30134-2

Publication details

Authors

Robert Moore; Patrick Donovan

Publisher

Schneider Electric

Year

2023

Document number

WP 100

Document language

English

Source type

Manufacturer

Access

Free to read

Licence

Copyright retained; citation only — the publisher’s terms apply to the original document

Citation