ICT Sustainability

Assessment and Strategies for a Low Carbon Future

An Online Graduate Course & Book by Tom Worthington MEd, FACS CP

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Previously we looked at the science of climate change and how electricity used to run computers and telecommunications can contribute to greenhouse gas emissions. Now 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 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.

Energy Consumption and Carbon Footprint of ICT Usage in Australia

The Energy Consumption and Carbon Footprint of ICT Usage in Australia (Philipson, 2010), estimated that ICT used 7% of all electricity generated in Australia and was responsible for 2.7% of the carbon emissions. Data centres made up 18.8%, PCs 15.8%, printers and imaging equipment 15.7% and servers 14.7%. Mobile phones and other portable devices, though widely used, accounted for only 1% of emissions

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  1. Greenhouse friendly policies: Some major organisations have made claims about their greenhouse friendly policies. For one organisation, from publicly available sources summarise:
    • Their energy strategy,
    • Any use of ICT in the strategy,
    • Any energy reduction targets
  2. Greenhouse reduction strategies in your organisation: Describe any greenhouse reduction strategies in your organisation (or an organisation you are familiar with). Do these involve ICT? Are there measures or targets for CO2e, embodied energy or energy use for telecommunications, data centres or desktop PCs?

Next: Energy Saving - Data Centres and Client Equipment.

About the book: ICT Sustainability: Assessment and Strategies for a Low Carbon Future

Edition Notice

ICT Sustainability is about how to assess, and reduce, the carbon footprint and materials used with computers and telecommunications. These are the notes for an award winning graduate course on strategies for reducing the environmental impact of computers and how to use the Internet to make business more energy efficient.

Copyright © Tom Worthington, 2017

Second edition.

ISBN: 978-1-326-96794-9. (Hardcover)
ISBN: 978-1-326-95850-3. (Paperback)
ISBN: 978-1-326-95849-7. (ePub eBook)
ISBN: 978-1-326-96791-8. (PDF eBook)

Cover shows Power on-off symbol: line within a circle (IEC 60417-5010).

These notes have been used for the courses:

  1. Green Technology Strategies: offered in the Computer Professional Education Program, Australian Computer Society (first run as "Green ICT Strategies" in February 2009),
  2. ICT Sustainability (COMP7310), in the Graduate Studies Select program, Australian National University (first run July 2009), and
  3. Green ICT Strategies (COMP 635), Athabasca University (Canada). Adapted for North America by Brian Stewart.

Course materials available free on-line, under at Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license at http://www.tomw.net.au/ict_sustainability/