Emission Factor Library
Search the public catalogue, manage custom factors, and browse the NACE tree.
What the emission factor library is
An emission factor converts an activity into greenhouse gas emissions: multiply what you did, such as litres of diesel burned or kWh of electricity bought, by the factor that matches it, and you get a figure in kg or tonnes of CO2 equivalent. This page is the public catalogue of the factors Future Fluent calculates with. It is free to browse, with no account needed, because the number behind a reported emission should be something anyone can look up and check.
Where the factors come from
The catalogue draws on published, openly licensed datasets rather than a private in-house list: the UK government conversion factors (DEFRA), the US EPA emission factor data, EXIOBASE for spend-based factors, and ADEME Base Carbone. Each factor keeps the source it came from, so you can see which dataset a number belongs to and cite it in your own report. The spend-based factors can also be browsed through the NACE industry tree, where values are expressed per euro spent rather than per physical unit.
Why the year on a factor matters
Factors are published in annual vintages and they move. A national grid gets cleaner or dirtier, a source revises its methodology, and the value for the same activity changes from one year to the next. Every factor in the catalogue therefore carries its data year, and you can filter by it. The rule of thumb is to match the factor year to the year you are reporting on, and to keep a note of which vintage you used so a later reader can reproduce your figure.
For how factors fit into a full calculation, and what disclosure B3 asks for, see GHG calculation for VS (VSME) reporting.