Understanding Scope 1, Scope 2 and Scope 3 Emissions

When an organisation starts to measure its environmental impact, they often ask: what’s the difference between Scope 1, 2, and 3 emissions? Our sustainability experts offer the below introduction to greenhouse gas emissions, explaining what they are and how they are measured.

What are Greenhouse Gas (GHG) emissions?

Greenhouse Gas (GHG) emissions are broken down into three categories: Scope 1, Scope 2, and Scope 3. The Greenhouse Gas Protocol created these scopes as part of its Corporate Accounting Reporting Standard. Emissions are gases and other particles released into the atmosphere because of human activities such as burning fuels. The most impactful greenhouse gases emitted by humans include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and fluorinated gases. A carbon footprint is measured in tonnes of CO2 equivalent (CO2e), a standard unit for measuring carbon footprints.

How are emissions broken down into Scopes 1, 2, and 3?

Scope 1

Scope 1 includes all direct emissions generated from sources that are directly owned or controlled by an organisation. These include natural gas at local or international sites, fuel for company vehicles, diesel for generators, and refrigerant gases. For example, a food delivery company would measure its diesel consumption from owned delivery vans, gas consumption from its owned sites, and refrigeration from its owned warehouses.

Scope 2

Scope 2 includes all indirect emissions from the generation of electricity purchased and used by an organisation. These can be measured as location-based or market-based. Location-based emissions use the average fuel mix of the electricity grid based on location. Market-based emissions are more specific to the actual supply used and take into account the tariff purchased, including the percentage of coal, gas, oil, nuclear, biomass, wind, and solar in the energy mix.

Scope 3

Scope 3 includes all indirect emissions that occur in an organisation’s value chain — activities that they do not own or control. These are usually the greatest share of an organisation’s carbon footprint. Scope 3 is broken down into 15 categories covering upstream activities (e.g. purchased goods and services, business travel, employee commuting, waste) and downstream activities (e.g. use of sold products, end-of-life treatment).

What do carbon emissions results look like?

Compare Your Footprint offers carbon footprint calculation software to help organisations measure and manage their GHG emissions across Scopes 1, 2, and 3. Organisations get started by identifying what data to collect under each scope. The data inputted can include electricity, gas, liquid fuels, waste, water, materials purchased, home working, travel, and much more. There are over 10,000 usage data conversions to choose from. Once the data has been entered, the organisation can create a results report to see the tonnes of CO2e generated across each category.