Scope 1:
direct emissions, explained simply.

The Scope 1 covers greenhouse gas emissions directly produced by your company: what you burn yourself, on your own premises or in your own vehicles. It’s the easiest scope to grasp, because you are the direct source and the data already exists in your accounting records.

Scope 1: the GHG Protocol definition

The GHG Protocol, the international standard adopted by the CSRD and ADEME, defines Scope 1 as direct emissions from sources owned or controlled by the company. Unlike Scope 2 (purchased energy) or Scope 3 (the rest of the value chain), Scope 1 corresponds to what literally comes out of a chimney, an exhaust pipe, or a leak on your own site.

The GHG Protocol distinguishes four source categories. For the vast majority of SMEs, only the first two represent a significant volume.

1. Stationary combustion : Natural gas, heating oil, or propane burned on-site to heat your premises, power an industrial furnace, or a boiler. This is generally the leading Scope 1 item for an SME with a production site or a large building.
2. Mobile combustion : Fuel (diesel, petrol, LPG) consumed by vehicles your company owns or leases long-term: delivery vans, commercial vehicles, combustion-engine forklifts, company car fleets.
3. Fugitive emissions : Refrigerant gas leaks from your air conditioning systems, cold rooms, or heat pumps. Often overlooked, they can weigh heavily: these gases have a global warming potential hundreds to thousands of times greater than CO₂.
4. Process emissions : Certain chemical or industrial reactions (surface treatment, cement production, metallurgy) emit CO₂ independently of energy combustion. Mainly affects heavy industry, rarely service or trading SMEs.

For a service-sector SME with no vehicle fleet or industrial site, Scope 1 is often close to zero, or even absent. For an industrial SME that heats its workshops with gas or owns several utility vehicles, it can instead represent a substantial item, sometimes larger than Scope 2.

How to calculate your Scope 1 without a carbon expert

The most accessible method for an SME relies on the ADEME Base Carbone emission factors, applied to the quantities consumed or, failing that, to the amounts spent.

• Stationary combustion: start from your gas or heating oil invoices. The consumption in kWh (shown on the invoice) multiplied by the ADEME emission factor for the fuel gives the result directly in kgCO₂e.
• Mobile combustion: start from the litres of fuel purchased (fuel cards, expense reports, fleet invoices) or, failing that, the kilometres travelled by vehicle type. Each fuel has its own emission factor per litre.
• Fugitive emissions: an exact calculation requires the quantity of refrigerant refilled during maintenance of your air conditioning systems. If this data isn’t available, a default estimate based on the number and age of the equipment remains acceptable for a first assessment.

When the physical quantity isn’t known, the monetary method (amount spent × emission factor per euro) gives an acceptable estimate for a first submission — less precise, but sufficient for most client questionnaires.

A worked example for a mid-sized SME

For an industrial SME with 40 employees, a gas-heated workshop, and 4 diesel utility vehicles:

• Stationary combustion (gas): on the order of 30 to 80 tCO₂e per year depending on the heated surface area and the building’s insulation
• Mobile combustion (diesel fleet): on the order of 15 to 40 tCO₂e per year depending on annual mileage
• Fugitive emissions: generally under 5 tCO₂e per year, unless there’s a significant air conditioning or commercial refrigeration fleet

For comparison, these orders of magnitude generally remain well below the same company’s upstream Scope 3, which includes all of its purchases.

The most common mistakes

• Forgetting long-term leased vehicles. A vehicle under a long-term lease or lease-to-own arrangement remains under your operational control: its fuel counts as Scope 1, even if you don’t own it.
• Ignoring refrigerant fluids. A single air conditioning refill can represent the equivalent of several tonnes of CO₂ because of these gases’ high global warming potential.
• Confusing Scope 1 and Scope 2. The electricity you purchase, even to run your machines, falls under Scope 2, not Scope 1. Only the energy you burn yourself counts here.
• Double-counting with a transport provider. If an external carrier delivers your goods, that fuel is in their Scope 1, and in your Scope 3 (upstream or downstream transport category) — never in your own Scope 1.

To complete your assessment, two related guides: Scope 2, purchased energy, and Scope 3, the most significant part for most SMEs. No specific client request? Here’s why you should calculate your carbon footprint anyway.

Oakbon calculates your Scope 1, 2 and 3
automatically, in 2 hours.

Drop in your accounting export: FEC, Pennylane, Sage, or any CSV or Excel file. Oakbon identifies your energy and fuel expenses, applies ADEME emission factors, and generates a complete report, ready to send.

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