Measure your carbon emissions

Knowing how much carbon your business produces is an important step for managing costs and moving towards net zero.

It is not yet required by law but taking steps now will prepare you for future changes.

Do a basic calculation

The simplest way to get started is to collect yearly amounts of electricity use, fuel consumption and refrigerant top-ups related to your business.

Using 12 months of data allows seasonal variations to average out. It can be helpful to align the measurement period with your financial or calendar year.

To do this you will need yearly totals for:

  • electricity in kilowatt hours (kWh)
  • natural gas in kWh or cubic meters
  • liquefied petroleum gas (LPG) in litres
  • petrol or diesel in litres
  • refrigerant top-ups in kilograms

Use the SME Carbon Footprint Calculator to calculate your carbon emissions in metric tonnes per year.

Once you know this number, you can benchmark against it and track your progress and make the SME Climate Commitment.

Use the GHG Protocol: Scopes 1, 2 and 3

The Greenhouse Gas (GHG) Protocol is widely used to report carbon emissions to the government, suppliers, investors and others.

It puts emissions into categories called ‘scopes’ and provides a more complete accounting of the carbon produced by your business. To comply with the GHG Protocol you must measure Scopes 1 and 2. Scope 3 is optional.

Scope 1

Emissions produced directly from your business activities, including:

  • petrol or diesel used by company vehicles
  • LPG, natural gas or other fuel burned on site
  • refrigerant losses
  • land owned by the business or under its operation

Scope 2

Emissions produced from the electricity, cooling, heat and steam your business buys or acquires.

Scope 3

Emissions produced indirectly from your business activities, including:

  • water supply and treatment
  • shipping and distribution
  • employee commuting
  • goods and services you buy
  • how customers use your goods and services
  • financial services, including emissions from pension funds and investments made by banks holding company money

Calculate using conversion factors

For the same mass of emissions, different greenhouse gases warm the atmosphere different amounts.

Use the government-agreed conversion factors to express non-CO2 emissions in terms of an equivalent CO2 warming effect – a metric known as ‘CO2-equivalent’, or ‘CO2e’.

Check GOV.UK for the latest conversion factor spreadsheets.

To help decide what should be counted in Scope 3 calculations, use the GHG Protocol’s Scope 3 Evaluator. You can also download their detailed guide (PDF) to measuring Scope 3 emissions.

Hire a consultant

If you can’t measure emissions on your own, consider hiring a sustainability consultant. They can create a strategy to measure emissions in line with your business needs.