Scope 1 Emissions

What is Scope 1 Emissions?

Scope 1 emissions, as defined by the GHG Protocol Corporate Standard, cover all direct greenhouse gas emissions from sources that are owned or controlled by the reporting company. These are the emissions an organisation has the most direct ability to measure and reduce.

Scope 1 emissions fall into four main categories. Stationary combustion includes emissions from burning fuels in fixed equipment such as natural gas boilers, oil-fired heaters, diesel generators, and industrial furnaces. Mobile combustion covers emissions from company-owned or company-leased vehicles, including cars, vans, trucks, and heavy plant machinery running on petrol, diesel, LPG, or CNG. Process emissions arise from industrial processes themselves — for example, the chemical reaction that produces CO₂ during cement manufacturing, or the use of solvents and chemicals in production. Fugitive emissions are unintentional leaks of greenhouse gases, most commonly from refrigeration and air conditioning units (which release hydrofluorocarbons, or HFCs), gas distribution systems, or coal mine methane.

To calculate Scope 1 emissions, an organisation collects activity data for each source — typically the volume of fuel consumed (in litres, kWh, or tonnes) or the quantity of refrigerant recharged — and multiplies it by the appropriate emission factor. In the UK, the DEFRA/DESNZ emission factors are updated annually and provide conversion ratios for all major fuel types and refrigerant gases, covering CO₂, CH₄ (methane), and N₂O (nitrous oxide), expressed as a combined CO₂ equivalent (CO₂e) figure.

For most service-sector businesses, the largest Scope 1 sources are natural gas heating and company vehicle fleets. For manufacturers, industrial process emissions and on-site fuel combustion are typically dominant. Organisations with large refrigeration systems — such as supermarkets, cold storage facilities, and data centres — may find that fugitive HFC emissions are a significant component.

Scope 1 is mandatory under nearly all carbon reporting frameworks, including SECR, the GHG Protocol, CSRD, ISSB (IFRS S2), CDP, and the UK Carbon Reduction Plan (PPN 06/21). It is typically the most straightforward scope to calculate because the data comes from internal records — fuel purchase invoices, vehicle mileage logs, and refrigerant service records.

Reduction strategies for Scope 1 include electrifying vehicle fleets, switching from natural gas to heat pumps or renewable heat, improving boiler efficiency, reducing refrigerant leaks through better maintenance, and transitioning to lower-GWP (global warming potential) refrigerants.

How Climatise Helps

Climatise automatically categorises your fuel, gas, and refrigerant data into Scope 1, applies the correct DEFRA emission factors by fuel type and year, and flags any data gaps. The platform handles the conversion from raw units (litres, kWh, kg) to tCO₂e without manual calculation.

Frequently Asked Questions