What is a CO2 footprint?
A CO2 footprint is the total emission of greenhouse gases caused by your organisation in a given period, usually a calendar year. You express it in CO2 equivalents (CO2e), so that gases such as methane and refrigerants are counted too, based on their effect on the climate.
The most widely used method comes from the GHG Protocol, the international standard for measuring greenhouse gases. You first define the boundaries of your organisation and then divide the emissions into three scopes. For many SMEs this is the basis for quotes, tenders, bank questions and a sustainability report.
Scope 1, 2 and 3 in plain words
Scope 1 is what you emit yourself: natural gas for heating or processes, fuel in your own vehicles and machinery, and refrigerant leaking from your own installations. You burn, drive or leak yourself, so the emissions are yours.
Scope 2 is the emission that arises elsewhere for energy you buy: electricity, but also purchased heat or cooling. You do not see the chimney, but your consumption causes it, which is why it counts for you. Electricity from your energy supplier is the best-known example.
Scope 3 is everything else in your chain: purchased materials and services, transport by others, business travel in vehicles you do not own, commuting, waste processing and the use of what you sell. For many organisations this is the largest part of the emissions, and at the same time the hardest to measure.
Which data do you need?
Start with the data you already have. Usually it sits in invoices, fuel card overviews and expense claims. Note for each item the quantity, the unit, the period and the source, otherwise you cannot justify it later. If you have several locations or vehicles, use the same layout everywhere.
- Natural gas in cubic metres, from the energy bill (scope 1)
- Fuel for company vehicles and machinery in litres, from fuel cards or invoices (scope 1)
- Refrigerant topped up during maintenance, in kilograms (scope 1)
- Electricity in kilowatt-hours, from the energy bill or meter readings (scope 2)
- Business kilometres in private cars, by train or by plane, from expense claims (scope 3)
- Commuting, waste and purchased products or services, once you want to go further (scope 3)
How does calculating with emission factors work?
The calculation rule is always the same: activity times emission factor equals emissions. The activity is what you consumed, for instance litres of diesel. The emission factor says how much CO2e one unit of it causes. Units must match: cubic metres of gas need a factor per cubic metre, not a factor per kilowatt-hour.
You do not make up emission factors yourself. Use a public, annually updated list for the Netherlands and note which list and which year you use. If your supplier has its own substantiated factor, for example for electricity or heat, you can use it if you can demonstrate it. That way your figure can be traced and repeated later.
Worked example for a fictional installation company
The company has a workshop, an office and a fleet of vans. The factors below are rounded, illustrative numbers to show the calculation. They are not current values: for your own calculation you always use the official list for the year you report on.
- Natural gas, scope 1: 12,000 m3 x 2.0 kg CO2e per m3 = 24,000 kg, so 24 tonnes
- Diesel for vans, scope 1: 30,000 litres x 3.0 kg per litre = 90,000 kg, so 90 tonnes
- Electricity, scope 2: 50,000 kWh x 0.4 kg per kWh = 20,000 kg, so 20 tonnes
- Business kilometres in employees' own cars, scope 3: 40,000 km x 0.2 kg per km = 8,000 kg, so 8 tonnes
How to read the result and approach scope 3
Together that is 142 tonnes of CO2e: 114 tonnes in scope 1, 20 tonnes in scope 2 and 8 tonnes in scope 3. Diesel use accounts for more than 60 percent of the total. Such an overview immediately shows where reduction pays off most, and which part you tackle first.
Scope 3 cannot be completed in one go, and does not need to be. Start with what you can measure, such as business kilometres, commuting and waste, and estimate the rest based on spend or weight. State which parts you include and which you do not. Then ask your biggest suppliers and subcontractors for data and improve one part each year.
Common mistakes when calculating
Most mistakes in a footprint are not calculation errors but administrative ones. A figure is only right when you can show where it comes from, which factor goes with it and which period it covers. A fixed way of working prevents most pitfalls.
- Mixing up units, such as cubic metres of gas and kilowatt-hours
- Using an old factor year or not noting the source
- Leaving gaps in the year or counting a period twice
- Calculating only CO2 and forgetting other greenhouse gases
- Ignoring scope 3 without stating that you do so
- Not marking estimates as estimates
How do you record reduction?
Choose a base year: the year you will compare with later, and record the footprint of that year with all sources and factors. Formulate a target with a deadline, for example an absolute decrease in tonnes or a decrease per employee or per project. Link each target to measures with an owner, deadline and expected effect.
In the example, 10 percent less diesel use already saves 9 tonnes, more than all business kilometres combined. Measure again after a year with the same boundaries and method, and explain the difference. If your organisation changes substantially, for instance through an acquisition, recalculate the base year so that you compare like with like.
How BrydgeOne supports this
In Energy & Emissions you choose a category under New source, such as natural gas, electricity, diesel or commuting, and that determines the emission factor, unit, scope and scope category. The platform calculates with emission factors versioned every year; CO2e is always calculated and never entered manually. Per reporting year you see which periods have been registered and which are still open.
A supplier-specific factor overrides the platform value, and the annual report as a PDF shows the factors used as an audit trail. From a source you create a reduction objective in Objectives & KPIs, and VSME & sustainability reuses the data in your report. Supplier management helps you evaluate and monitor suppliers, a starting point for your scope 3 conversations.
© 2026 BrydgeOne. General information, not legal or other professional advice. No rights can be derived from this article.