A4.14.1 Carbon Footprint


A Carbon Footprint is the amount of carbon emissions (both direct and indirect) that can be attributed to what the footprint relates to. This may be a person, a product, an event or an organisation. It should be noted that the term ‘Carbon Footprint’ often refers to the amount of emissions of all Greenhouses Gases, not just carbon.

A carbon footprint is measured in tonnes of carbon dioxide equivalent (tCO2e). The carbon dioxide equivalent (CO2e) allows the different greenhouse gases to be compared on a like-for-like basis relative to one unit of CO2.

CO2e is calculated by multiplying the emissions of each of the six greenhouse gases by its 100 year global warming potential (GWP).

A carbon footprint considers all six of the Kyoto Protocol greenhouse gases:

  • Carbon dioxide (CO2)
  • Methane (CH4)
  • Nitrous oxide (N2O)
  • Hydrofluorocarbons (HFCs)
  • Perfluorocarbons (PFCs)
  • Sulphur hexafluoride (SF6).


The main types of carbon footprint for organisations are:

1. Organisational carbon footprint

Emissions from all the activities across an organisation, including buildings’ energy use, industrial processes and company vehicles.

2. Value chain carbon footprint 

Includes emissions which are outside an organisation’s own operations (also known as Scope 3 emissions).  This represents emissions from both suppliers and consumers, including all use and end of life emissions.

3. Product carbon footprint

Emissions over the whole life of a product or service, from the extraction of raw materials and manufacturing right through to its use and final reuse, recycling or disposal.


Organisational carbon footprints

An organisational carbon footprint measures the direct and indirect GHG emissions arising from all the activities across an organisation.

Quantifying GHG emissions will help you understand what your key emission sources are, how your organisation contributes to global emissions, and what opportunities you have to reduce your emissions. You can then develop a carbon reduction plan, identifying ways to reduce your carbon footprint and limit emissions from future activities – and then measure what progress you have made.


There are generally considered to be three different scopes of emissions that should be monitored to calculate a carbon footprint:


  1. Direct
  • Fuel combustion.
  • Fugitive emissions.
  • Company vehicles.


  1. Indirect      (a)
  • Electricity purchased for your organisation’s use.
    • Although you’re not directly in control of the emissions, by using the energy you are indirectly responsible for the release of CO2.


  1. Indirect      (b)
  • Any other indirect emissions from sources outside your direct control. E.g.
    • Employee business travel.
    • Waste disposal.
    • Contractor owned vehicles.
    • The production of purchased materials.


Please note that the Greenhouse Gas Protocol (a widely used standard that sets out how to account for your GHG emissions) refers to the three groups as ‘scope 1, 2 and 3’:

The Carbon Trust published “Carbon footprinting: The next step to reducing your emissions Management guide” in 2012. This is a useful introduction to Carbon Footprint and is available here: A4.14.1 Carbon Trust Footprinting guide

Online Carbon Footprint tools are available on the internet (please click on the image below):

Act on CO2:


The Environment Agency have developed a carbon calculator, which is available here: A 4.14.1 EA carbon calculator