
Even though technological and operational improvements have increased aircraft fuel efficiency over the years, the growing demand for flights continues to drive up total aviation emissions. On top of that, aviation is considered one of the most challenging sectors to decarbonize, making it likely that its share of global emissions will increase in the coming years. However, the aviation industry will have to reduce their emissions as the EU Green Deal policy initiative sets out the ambitious target of being climate neutral by 2050. For the transportation sector, the EU Green Deal’s goal is to reduce emissions by 90% by 2050 compared to 1990 emission levels. One potential solution to reducing emissions is the use of Sustainable Aviation Fuel (SAF).
What is SAF?
SAF is an alternative fuel made from biogenic feedstocks instead of fossil fuels. It is a way to reduce aviation emissions in the short term as it is compatible with the existing aircraft fleet. Upon combustion of SAF in the aircraft engine, the same amount of CO2 is emitted into the air as was previously absorbed by its feedstock. Therefore, no new CO2 is added to the atmosphere, in contrast to fossil-based jet fuel. Although this sounds great, it should be noted that during the sourcing and production process of SAF emissions originating from fossil fuels are released into the air. Depending on the feedstock and the production process used to produce SAF (resulting in different SAF types), total lifecycle emissions can be reduced by 30-95% by using SAF instead of fossil-based jet fuels.
SAF is a way to reduce aviation emissions in the short term as it is compatible with the existing aircraft fleet
Although SAF can potentially reduce emissions, its consumption is still very low. The two main causes are high prices and low supply. SAF is between 1.5 and 6 times more expensive than fossil-based jet fuel. The SAF supply in 2020 was only 0.05% of the total jet fuel consumption in Europe. The development of SAF prices and supply will be essential in the coming years to encourage the uptake of SAF.
DTM supply chain design tool can be used to evaluate different scenarios
Using DTM’s supply chain design optimization tool, it is possible to model all aspects of supply chains. The tool is accurate and detailed which contributes to obtaining specific and meaningful results. The tool has been used to study the SAF and fossil-based jet fuel supply chains under different circumstances. For instance, the effects of changing prices and supply quantities within the SAF and fossil-based jet fuels supply chains were modelled. The model allows to evaluate the dynamics of multiple objectives, such as cost and emissions, in the supply chains under varying conditions.
Taxation could make SAF more price competitive
In addition to the supply chain structure, other measures were investigated, such as increasing tax levels on fossil-based jet fuels. This taxation would lead to higher prices, encouraging the uptake of SAF. As airlines pass these increased fuel costs on to passengers by raising ticket prices, flight demand may decrease due to price elasticity. This combination of greater SAF usage (assuming adequate SAF supply) and lower flight demand could significantly reduce aviation emissions.
Can SAF achieve the emission reduction goals?
Even if the entire fuel demand were to be covered by SAF, the EU Green Deal emission reduction goals are not achievable by the 2022 announced ratios of SAF types. To enhance emission reduction by using SAF, the focus should be on SAF types and feedstocks with the lowest lifecycle emissions. However, to meet the EU Green Deal goals by only using low-emission SAF types (and feedstocks), their expected supply capacities should at least double. Therefore, further technological and operational improvements, as well as the development of zero-emission aircrafts, are essential in achieving EU Green Deal emission goals.
Conclusion: SAF is an improvement but not the silver bullet
To answer the title question: No, it is not only SAF that is the key to achieving EU Green Deal emission reduction goals by 2050. Other emission reduction measures are required to reduce aviation emissions by 90% in 2050 compared to 1990 levels. However, SAF offers a good solution to reduce aviation emissions in the short term if its consumption goes up. This can be achieved by introducing taxation on fossil-based jet fuel to make SAF’s price more competitive. Besides, the supply of SAF, especially the SAF types with low lifecycle emissions, should continue to increase.