DEFRA 2024
Conversion Factors for Company Reporting
Published annually by the UK Department for Environment, Food & Rural Affairs (DEFRA) and the Department for Energy Security and Net Zero (DESNZ), these conversion factors are the mandatory dataset for UK Streamlined Energy and Carbon Reporting (SECR) and widely adopted internationally as a credible, peer-reviewed emission factor source. CarbonTrace uses DEFRA 2024 for all activity-based calculations where applicable.
Download DEFRA 2024 Factors (GOV.UK)Why DEFRA Factors Are Used Globally
Annual Updates
Published every June, reflecting the latest UK energy mix, fuel compositions, and scientific updates from IPCC. No guesswork — each factor has a documented derivation.
Full Lifecycle
Covers both combustion-only and well-to-wheel (WTW) factors, allowing organisations to report on Scope 1 combustion or full upstream supply chain emissions.
SECR Compliance
Mandatory for UK companies subject to Streamlined Energy and Carbon Reporting. Aligns with ISO 14064-1 and GHG Protocol.
International Use
Widely adopted by multinational companies as a credible fallback for non-UK operations where national grid factors are unavailable.
Key Emission Factors (2024)
Selected factors from the DEFRA 2024 dataset. All values are in kg CO₂ equivalent (CO₂e) and include CO₂, CH₄ and N₂O using IPCC AR5 GWP100 values (as per DEFRA's current methodology; AR6 transition expected in future publications).
| Category | Unit | Factor (CO₂e) | Scope | Notes |
|---|---|---|---|---|
| Fuels — Natural Gas | per kWh (gross CV) | 0.18254 kg CO₂e | Scope 1 | Includes CO₂, CH₄ and N₂O. Updated annually to reflect grid mix. |
| Fuels — Diesel (road) | per litre | 2.50663 kg CO₂e | Scope 1 | Well-to-wheel factor includes upstream extraction and refining. |
| Fuels — Petrol (road) | per litre | 2.17205 kg CO₂e | Scope 1 | Combustion factor: 2.27 kg CO₂e/litre (tank-to-wheel). |
| UK Grid Electricity | per kWh | 0.20493 kg CO₂e | Scope 2 | Location-based. Market-based method requires REGOs / PPAs. |
| Business Travel — Short-haul Economy | per passenger-km | 0.15302 kg CO₂e | Scope 3 | Includes radiative forcing multiplier (RFI = 1.9). |
| Business Travel — Long-haul Economy | per passenger-km | 0.14787 kg CO₂e | Scope 3 | Includes radiative forcing multiplier (RFI = 1.9). |
| Water Supply (UK) | per cubic metre | 0.149 kg CO₂e | Scope 3 | Treatment and pumping energy included. |
| Waste — Landfill (mixed) | per tonne | 467.42 kg CO₂e | Scope 3 | Methane capture assumptions vary by site type. |
| Waste — Recycling (mixed paper) | per tonne | 21.69 kg CO₂e | Scope 3 | Avoided emissions from recycling not included in this factor. |
Full dataset: 500+ factors across fuels, electricity, transport, materials, waste, water, and refrigerants.Download full spreadsheet →
News & Updates
DEFRA publishes 2024 Greenhouse Gas Conversion Factors for Company Reporting
GOV.UK · June 2024
UK SECR (Streamlined Energy and Carbon Reporting) — mandatory use of DEFRA factors for UK operations
GOV.UK · 2024
DEFRA 2024 update: UK grid electricity intensity falls to 0.205 kg CO₂e/kWh — lowest recorded
DESNZ · 2024
UK National Grid ESO: Great Britain grid reaches 50% renewables share in 2024
National Grid ESO · 2024
DEFRA 2024 factors built into every calculation
No manual lookups — CarbonTrace applies the correct DEFRA factor automatically.