You cannot manage what you do not measure. A greenhouse gas (GHG) inventory tells you where your emissions come from, so you can decide where to act first. Most inventories follow the GHG Protocol, which groups emissions into three scopes.
The three scopes
- Scope 1: direct emissions from sources you own or control, such as fuel burned in company vehicles, generators and boilers.
- Scope 2: indirect emissions from the electricity, steam, heating or cooling you purchase.
- Scope 3: all other indirect emissions in your value chain, from purchased goods and transport to business travel, waste and the use of your products.
A practical way to begin
First decide the boundary of your inventory, such as which sites and subsidiaries to include. Then collect activity data (litres of fuel, kilowatt-hours of electricity, distances travelled), apply recognised emission factors, and calculate your totals. Most companies start with Scope 1 and 2, where data is easiest to obtain, and then screen Scope 3 to find the categories that matter most.
The first inventory will never be perfect. What matters is a transparent method you can improve each year.
From measurement to action
Once you have a baseline, you can set reduction targets, prioritise efficiency measures and evaluate options such as renewable energy. A clear, documented inventory also makes it much easier to answer customer and lender questions about your climate performance.
