Understanding Scope 1, 2 and 3 Emissions: A Simple Guide
A straightforward breakdown of the three emission scopes every organisation needs to measure — with real-world examples and average figures for UK SMEs.
If you're creating a Carbon Reduction Plan (CRP) or making a net-zero pledge, you'll need to understand the three "scopes" of greenhouse gas emissions. This guide explains each scope in plain language, with practical examples and indicative figures for UK small and medium enterprises.
What Are Emission Scopes?
The Greenhouse Gas Protocol divides emissions into three categories, or scopes, based on where they originate relative to your organisation. Together, they give a complete picture of your carbon footprint.
Scope 1: Direct Emissions
What it covers: On-site fuel combustion, company-owned vehicles, and fugitive emissions (e.g. refrigerant leaks) that your organisation directly controls.
Examples:
- Natural gas burned in your office boiler
- Diesel or petrol used by company vans and cars
- Emissions from on-site manufacturing processes
Average for UK SMEs: approximately 45 tCO₂e per year
Scope 2: Energy (Indirect)
What it covers: Purchased electricity, heating, and cooling, indirect emissions that result from the energy you consume but don't generate yourself.
Examples:
- Electricity powering your office lights, computers, and servers
- District heating or cooling systems
- Purchased steam for industrial processes
Average for UK SMEs: approximately 120 tCO₂e per year
Scope 3: Supply Chain (Value Chain)
What it covers: Everything else, business travel, procurement, waste disposal, employee commuting, and upstream/downstream transport in your value chain.
Examples:
- Business flights and rail travel
- Products and services you purchase from suppliers
- Waste sent to landfill
- Employee commuting
- Downstream distribution of your products
Often accounts for 70% or more of an organisation's total carbon footprint
Why All Three Scopes Matter
Many organisations start by measuring Scope 1 and 2 because the data is more readily available. However, for most service-sector businesses, Scope 3 represents the largest portion of emissions. The UK Government's PPN 06/21 guidance requires suppliers bidding for major government contracts to include Scope 3 in their Carbon Reduction Plans.
Getting Started
Zero to Green Pledge's Carbon Reduction Plan generator walks you through all three scopes step by step. You don't need a consultant, our guided wizard helps you identify your emission sources, set a baseline, and create a compliant CRP in under 10 minutes.