# What emission factor do I use for biodiesel made from used cooking oil?

Canonical: https://senseible.earth/answers/used-cooking-oil-biodiesel-emission-factor

CO2 from burning biodiesel is biogenic, so report it outside the scopes. Methane and nitrous oxide from the engine stay in Scope 1. For a blend, only the diesel share counts as fossil CO2. Collection, processing and transport of the oil go in Category 3, and published factors include them.

## For a blend

1. Split litres into the diesel share and the biodiesel share from the blend ratio.
2. Diesel share: 2.68 kg CO2 per litre in Scope 1.
3. Biodiesel share: biogenic CO2 as a separate line.
4. Add methane and nitrous oxide for all litres.

## Prove the feedstock

Keep the supplier's declaration that the fuel is from used cooking oil. Without it, use a general biodiesel factor.

## What Senseible does here

Senseible reads bills, fuel invoices and production records into dated, fingerprinted records, so the figure you send a buyer can be traced to its documents.

- [Biodiesel blends in Scope 1](https://senseible.earth/answers/biodiesel-blend-fleet-scope-1)
- [Pyrolysis oil from plastic](https://senseible.earth/answers/pyrolysis-oil-from-plastic-emission-factor)

Sources: [UK Government GHG conversion factors for company reporting](https://www.gov.uk/government/collections/government-conversion-factors-for-company-reporting), [GHG Protocol Corporate Standard](https://ghgprotocol.org/corporate-standard), [IPCC 2006 Guidelines for National Greenhouse Gas Inventories](https://www.ipcc-nggip.iges.or.jp/public/2006gl/)

Last reviewed 2026-10-22.