What is a carbon footprint?

A carbon footprint is the total greenhouse gas (GHG) emissions caused directly or indirectly by an organisation, project, event, or individual over a specific period, typically one year. It is measured in terms of carbon dioxide equivalent (CO₂e), which accounts for all greenhouse gases based on their global warming potential. 

To better understand and measure a carbon footprint, GHG emissions are divided into three categories, known as Scope 1, Scope 2, and Scope 3 emissions.

Scope 1 (Direct Emissions)

These are emissions that come from sources owned or controlled by the organisation. For example, emissions from company vehicles, on-site fuel combustion (such as boilers or generators), and industrial processes that directly emit GHGs fall under Scope 1.

Scope 2 (Indirect Emissions from Energy Use)

Scope 2 covers emissions from the generation of purchased electricity, steam, heating, and cooling consumed by the organisation. Although the emissions occur at the power plant that produces the energy, the organisation is responsible for them because it consumes that energy.

Scope 3 (Other Indirect Emissions)

Scope 3 includes all other indirect emissions that occur in an organisation’s value chain, both upstream and downstream. This could include emissions from employee commuting, business travel, the production and transportation of goods purchased by the organisation, and the use and disposal of products sold by the organisation. Scope 3 often represents the largest portion of an organisation’s carbon footprint.