From the book: Green Technology Strategies

The Global ICT Footprint

Last week we looked at the science of climate change and how electricity used to run computers and telecommunications can contribute to greenhouse gas emissions. This week we look at estimates of how much ICT contributes to Equivalent carbon dioxide (CO2e) to calculate the global ICT Carbon Footprint from use of telecommunications, data centres and desktop PCs.

The carbon footprint is an estimate of the amount of CO2e emitted by activity, in this case the use of ICT. The carbon footprint can be estimated from the embodied energy used to produce the ICT product and the energy used to operate the equipment.

Embodied energy (or Embodied carbon) refers to the energy used to manufacture, and supply to the point of use, a product or service. This includes the energy necessary to extract the raw material, to transport, manufacturing, assembly, installation as well as disposal of the equipment. ICT professionals would not normally be required to carry out detailed analysis of embodied energy for specific products, but use estimates supplied for a class of products, such as desktop computers or laptops.

Operating energy is a measure of the energy used to operate the ICT equipment. This can be measured directly using an energy meter (electric meter) which measures the electrical energy used. Alternatively the energy use may be estimated from the power the equipment uses (specified in Watt), multiplied by the estimated amount of time the equipment will be used (in Hours) to give the energy (in Kilowatt hours).

A Greenhouse gas conversion factor can then be used to convert energy consumed in kWh to kg of equivalent carbon dioxide. For example a computer using 200 W of power for 10 hours per day uses 2 kWh of energy. Multiplying by a conversion factor of 0.537 Kg CO2/kWh produces a total of 1.074 Kg CO2 per day.

Energy and greenhouse gas measures are only approximate. There have been attempts to estimate these for industry sectors, nations and the world.

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  1. Greenhouse friendly policies: Some major organisations have made claims about their greenhouse friendly policies. Collect information from publicly available sources (the Internet, newspapers, business magazines) and analyse one major organisation (in three paragraphs). Include references to your sources of information (with links to any web based information). This analysis should highlight:
    1. The energy strategy
    2. Any use of ICT in the strategy
    3. Any energy reduction targets
  2. ICT Carbon Footprint in your organisation: Explain the current status of measurement of ICT Carbon Footprint in your organisation (or an organisation you are familiar with) in 3 paragraphs. Are there measures or targets for CO2e, embodied energy or energy use for telecommunications, data centres or desktop PCs?
  3. Greenhouse reduction strategies in your organisation: Describe in up to three paragraphs any greenhouse reduction strategies in your organisation (or an organisation you are familiar with). Do these involve ICT?

From the book: Green Technology Strategies

This book is about how to reduce carbon emissions and achieve other environmental benefits by using computers and telecommunications technology. It is designed to be used within an online course for professionals, using mentored and collaborative learning techniques.

Title: Green Technology Strategies: Using computers and telecommunications to reduce carbon emissions

Copyright © , 2009

Publisher: Tomw Communications, PO Box 13, Belconnen ACT 2617, Australia. Website:

New edition available: ICT Sustainability: Assessment and Strategies for a Low Carbon Future, September 2011.

These notes are used for the courses:

  1. Green ICT Strategies (ACS25): offered in the Postgraduate Program of Open Universities Australia and available from 2010 to students of Curtin University, Griffith University, Macquarie University, Monash University, RMIT University, Swinburne University and the University of South Australia,

  2. Green Technology Strategies: offered in the Computer Professional Education Program, Australian Computer Society (first run as "Green ICT Strategies" in February 2009), and

  3. Green Information Technology Strategies (COMP7310), in the Graduate Studies Select program, Australian National University (first run July 2009).

The notes were first published as an electronic and paperback book in 2009 (Green ICT, Tom Worthington, Tomw Communications, 2009). Students can download or print their own copy of the e-book from the course learning management system, which is likely to be more up to date.

Green Technology Strategies: Using computers and telecommunications to reduce carbon emissions by Tom Worthington is licensed under a Creative Commons Attribution-Share Alike 2.5 Australia License, except for institutions covered by a Copyright Agency Ltd Statutory Licence.