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) and
Sulphur hexafluoride (SF6).
Types of carbon footprinting
The main types of carbon footprint for organisations are:
- Organisational carbon footprint
Emissions from all the activities across an organisation,
including buildings' energy use, industrial processes and company
- 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.
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.
Calculate your carbon footprint
Our carbon footprinting overview guide explains what is
included in organisational and product footprints, how you can
measure and communicate them, and the benefits of doing so. We also
set out the specific steps you need to take to calculate your
carbon footprint(s), and some of the key things to consider if you
Footprinting overview (CTV043)
For further support, find out more about our carbon footprinting
Greenhouse gas conversion factors are used to calculate
the amount of greenhouse gas emissions caused by energy
use. Our conversion factors
guide contains these factors along with a spreadsheet to
enter your usage and calculate carbon emissions.