ICT Sustainability

Assessment and Strategies for a Low Carbon Future

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

Skip to content

These terms are from the National Carbon Offset Standard (Australian Department of Climate Change, 2008), except where otherwise indicated.



Reduction of greenhouse gas emissions, or enhancement of greenhouse gas removal from the atmosphere by sinks.

Australian Emissions Unit (AEU)

An emissions unit issued under the Carbon Pollution Reduction Scheme (CPRS), also referred to as a 'carbon pollution permit'.

Annex I countries

Countries listed in Annex I to the United Nations Framework Convention on Climate Change (UNFCCC), including all developed (OECD) countries and the countries in transition in central and Eastern Europe (including Russia and Ukraine). In the context of the Kyoto Protocol, 'Annex I country' is used to refer to a party included in Annex I to the UNFCCC with a commitment inscribed in Annex B to the Kyoto Protocol.



Business as Usual - used in the context of predicting future data on the basis of existing practices.

Business unit

A unit that is recognised by an entity as having administrative responsibility for one or more facilities of the corporation.


Carbon dioxide equivalence (CO2-e)

A standard measure that takes account of the different global warming potentials of greenhouse gases and expresses the cumulative effect in a common unit.

Carbon footprint

A measure of the carbon dioxide equivalent emissions attributable to an activity, commonly used at an individual, household, organisation or product level.

Carbon neutrality

Commonly refers to a situation where the net emissions associated with a product or an organisation's activities are equal to zero through the acquisition and retirement of carbon offsets that meet additionality criteria.

Carbon offset

Represents a reduction in greenhouse gases, or enhancement of greenhouse gas removal from the atmosphere by sinks, relative to a business-as-usual baseline. Carbon offsets are tradeable and often used to negate (or offset) all or part of another entity's emissions.

Carbon sink

A natural or manmade reservoir that accumulates and stores carbon dioxide for an indefinite period.

Certified Emission Reduction unit

A Kyoto unit corresponding to one metric tonne of carbon dioxide equivalent emissions, and issued for verified emission reductions or removals achieved by projects approved under the Clean Development Mechanism (CDM). CDM projects undertaking afforestation and reforestation activities issue temporary and long term units known as tCERs and lCERs, which must be replaced after a specified period.


See: Carbon dioxide equivalence (CO2e).


See: Carbon dioxide equivalence: (CO2-e).


Global Warming Potential

(GWP) A system of multipliers devised to enable warming effects of different gases to be compared. For example, over the next 100 years, a gram of methane in the atmosphere is currently estimated as having 21 times the warming effect as a gram of carbon dioxide; methane's 100-year global warming potential is thus 21.

Greenhouse gases

The atmospheric gases responsible for causing global warming and climate change. The major GHGs are carbon dioxide (CO2), methane (CH4), nitrous oxide (N20), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6).


Thousand Million Tons of CO2e. See: Carbon dioxide equivalent.


ICT sustainability

"... the responsible acquisition, installation, use and disposal of information and communications technologies and services so as to utilise resources more effectively, improve efficiency and increase productivity, and reduce the environmental impact of operations. It also includes the effective use of information and communications technology to promote more sustainable practices in industry and the community. is the study and practice of using computers and telecommunications in a way which maximises positive environmental benefit and minimise the negative impact."

From: Australian Government ICT Sustainability Plan 2010 - 2015 (DEWHA 2010)


Kyoto Protocol

An international treaty created under the UNFCCC in 1997. It entered into force in 2005. Among other things, the Kyoto Protocol sets binding targets for the reduction of greenhouse gas emissions by developed countries and countries in transition. It includes individual emission reduction targets for Annex I countries to be met within the first commitment period of 2008-12.


Life cycle assessment

The compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product system throughout its life cycle.



Metric tons of CO2e (see: carbon dioxide equivalent).


National Greenhouse and Energy Reporting (NGER) System

The national reporting framework for information related to the greenhouse gas emissions, and energy production and use of corporations operating in Australia. The framework is established under Commonwealth legislation, which makes registration and reporting mandatory for corporations whose greenhouse gas emissions or energy production or use meet certain thresholds.



See: Carbon offset.


Scope 1 emissions

The release of greenhouse gas into the atmosphere as a direct result of activities at a Facility.

Scope 2 emissions

The release of greenhouse gas as a result of electricity generation, heating, cooling or steam that is consumed by a Facility.

Scope 3 emissions

The release of greenhouse gas into the atmosphere that is generated in the wider economy as a consequence of a facility's activities but that are physically produced by another Facility.


The removal of atmospheric carbon dioxide, either through biological processes (for example, photosynthesis in plants and trees), or geological processes (for example, storage of carbon dioxide in underground reservoirs).


terawatt hour

A terawatt hour (TWh) is a unit of energy equal to 1012 Watt hours.

TW h

See: terawatt hour


United Nations Framework Convention on Climate Change

An international treaty, adopted in 1992, aimed at achieving the stabilisation of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.

Next: Bibliography.

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, 2018

Third edition.

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

Latest version of 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/

Previous edition, 2017:

ISBN: 9781326967949 (Hardback)
ISBN: 9781326958503 (Paperback)
ISBN: 9781326967918 (PDF)
ISBN: 9781326958497 (ePub eBook via Lulu and Apple)
ASIN: B005SOEQZI (Kindle eBook)

Editions of these notes have been used for the courses:

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