Download 2025 GHG Conversion Factors

What’s New in the 2025 GHG Conversion Factors?

Here’s a summary of the most important changes:

Key Decreases in Emissions Factors:

UK Electricity: Down 15%, thanks to reduced use of natural gas in power generation and higher net electricity imports.
Electric Vehicles: Emissions from battery electric vehicles dropped by 11–22%, driven by a cleaner UK electricity grid and more efficient newer models.
Air Travel: Emissions fell by 16–42% as airline load factors improved, recovering from the low passenger numbers during COVID in 2021.
Freight Flights: Down 18–23%, also due to post-COVID recovery and better emissions modeling using updated aviation data.

Notable Increases in Emissions Factors:

Sports Plug-In Hybrid Vehicles: Up 16%, linked to a new high-emission model with strong 2023 sales.
Heavy Goods Vehicles (HGVs): Increased by 11–14% as average load per vehicle decreased, raising emissions per tonne transported.
Water Supply: Up 25%, based on updated utility data showing higher variation year-on-year.
Biofuels: Emissions factors varied widely, from –27% to +125%, depending on changes in feedstock mix and production processes.

Waste Management Emissions:

Construction & Other Waste Disposal: Down 27%, due to revised assumptions for emissions from Material Recovery Facilities (MRFs).

Methodology Updates:

Major changes are classified as:
- >5% for Scope 1 & 2 emissions
- >10% for Scope 3 emissions
Most fuels, refrigerants, and heat/steam factors remained largely unchanged.
Updates reflect the most recent data from 2023 vehicle registrations and energy sector reporting.

Overall Trends:
The 2025 updates show strong improvements in electricity-related and aviation emissions. However, some transport categories saw increases due to shifts in usage patterns and market trends.