Introduction

In 2019, the UK’s share of international aviation emissions peaked at its highest ever level.”

Aviation is one of the most intractable problems of decarbonisation. It is currently responsible for around eight per cent of UK emissions, the majority of which (93 per cent) are from international aviation, which is now integrated into the UK’s net zero carbon target. Unlike other parts of the economy, aviation emissions are rising and now sit 88 per cent above 1990 levels, as a result of steady increases in passenger demand.2 As the climate impact of other sectors dwindles, the share from flying will increase proportionately, assisted by policy allowing unconstrained growth in air travel.3 In 2019, the UK’s share of international aviation emissions peaked at its highest ever level. Despite government commitments to cut greenhouse gases by 78 per cent by 2035, there is little evidence to show the aviation sector will make significant progress towards this target and there are few supporting policies to cut emissions. The Department for Transport (DfT) has published multiple pathways for aviation that could come to fruition, depending on which technologies are most cost competitive and scalable. The main options for cutting carbon emissions are sustainable aviation fuel (SAF), zero emission aircraft and managing passenger numbers. Developing SAF is a primary choice for the government. This looks like a sensible approach, if integrated with other solutions; however, there are no significant policies or regulations in place to encourage and guide its use. In this report, we consider policies related to SAF, including the types of alternative fuel available and the consequences of different levels of uptake. We provide recommendations on how best to employ them to reduce aviation emissions.