Question to the Department for Transport:

To ask the Secretary of State for Transport, what assessment his Department has made of the comparative potential merits of different sustainable air fuels in the context of variation of lifecycle emissions within fuels denoted as the same type.

Sustainable aviation fuel (SAF) can be easily blended with conventional jet fuel and then used in existing aircraft and engines. We recognise that SAF can be made from different low carbon feedstocks and technology pathways, and that the detail of these impact the lifecycle emission savings from the fuel. When using sustainable feedstocks, such as wastes or renewable electricity, to produce SAF, its use can reduce carbon emissions by 70% compared to conventional jet fuel.

The SAF mandate, which will mandate jet fuel suppliers to supply increasing levels of SAF in the UK, will start in 2025. As a greenhouse gas (GHG) based scheme, it will encourage suppliers to source SAF that achieves the greatest emission reductions. It will also require the supplied SAF to meet a minimum emission reduction threshold, further strengthening our intention to support SAF that meets the highest sustainability criteria.

In 2022, under the renewable transport fuel obligation (RTFO) 48 million litres of SAF were supplied in the UK, with a reported average of 90% emission reductions. We expect the SAF mandate to build upon these volumes and increase the demand for SAF in the UK.