Sustainable aviation fuel (SAF) is a type of fuel that, unlike typical aviation fuel, is not produced from fossil-based raw materials, but instead from used cooking oils & fats or from agricultural waste. In comparison to conventional kerosene, SAF saves approximately 80% of carbon emissions. We use the quantity of SAF required to achieve full carbon reduction.
The aim of the development and widening rollout of SAF is to reuse carbon from existing sustainable biomass or gases and recycle it back into jet fuel so that fossil jet fuel refined from petroleum crude oil can be replaced. The process is a first step towards closing the CO2 cycle: fuel is burned, but the carbon emitted is reabsorbed, e.g. through biomass, and transformed into fuel again.
The UK government announced in October 2021 that it will provide £180 million in funding to support the development of sustainable aviation fuel (SAF) plants in the nation. The government said its ambition is to enable the UK’s aviation industry to utilise 10 per cent SAF by 2030, a milestone that is seen as a key factor in decarbonising the sector. It follows £21 million in funding for SAF announced last year.
In total, 100 million litres of SAF were produced in 2021. Currently, more than 48 airlines use or purchase SAF – the vast majority being in Europe and North America, where SAF rollout has been implemented the earliest and on the widest scale.
Heathrow was one of the earliest adopters of SAF within its development roadmap, and 60% of Heathrow’s airline partners are now said to have committed to converting at least 10% of their fuel supply into SAF by 2030.
The European Union will be introducing a SAF blending mandate by 2025. The requirement will start at 2%. It will then increase to 5% at 2030 with a minimum of 0.7% synthetic kerosene. There will then be a significant jump to 20% by 2035, with 5% synthetic fuel. By 2050, the target is set to 63% and 28%, respectively.
Although, by current projections, it is likely that production of SAF will fail to scale quickly enough to meet soaring demand for flying over the next three decades, leaving the industry still relying on carbon offsets to meet Net Zero pledges by 2050, it is also possible that SAF will be adopted on a larger scales by more airlines and airports across the world, and play a larger role in decarbonising air travel.
Widening the reach of SAF is far from the only solution to increase the emissions efficiency of air travel, too: there is huge potential to increase the efficiency of conventional aircraft (those powered by fossil fuel or SAF) through improvements to jet engines, wings, structures, and other systems. Next generation models of aircraft, such as the Airbus A320neo, offer around 20% efficiency gains on their predecessors. Replacing older aircraft still in operation with the latest models could save approximately 20 Mt CO2 by 2050. Currently, the UK is working through ICAO to ensure stringent international standards for aircraft emissions as technology improves.
There are also significant savings to be made at airports, where changes to operations – such as the use of a single engine for taxiing, and eventual use of an electric motor – could cut CO2 emissions by 60% in this phase of flight. Six UK airports currently hold Airports Council International (ACI) Europe Carbon Neutrality accreditation and many are setting more ambitious net zero targets. For example, Bristol Airport has announced that it intends to be the UK‘s first net zero airport (including its building, airfield and fleet) by 2030.
Only time will tell whether airports and airlines will employ these measures on a wide enough scale or on a sufficiently short timescale to meet international targets for emissions reductions from the aviation industry, but it is certainly promising that significant research is now being undertaken to ensure that the industry can scale up its efforts on a global scale when the time comes.
