Recent forecasts suggest that air transport demand will increase by an average of 4.3% per year. According to the European aviation organization EUROCONTROL, global air traffic is even expected to double by 2050. The steady growth of the aviation industry comes with an increase in environmentally harmful emissions. The most promising path to reducing CO2 emissions in aviation lies in Sustainable Aviation Fuels (SAF). Fuels are considered sustainable when they are either produced using biomass or synthetically produced by means of renewable energies and CO2.
SAF are intended to replace conventional fuels and are on the agenda of numerous players in the industry. If the full lifecycle of SAF is taken into account, CO2 emissions can be reduced by 80% compared to conventionally used fossil-based fuels.
Since SAF were approved for commercial use, more than 45 commercial airlines have already performed SAF flights. In December 2021, United Airlines became the first to demonstrate a commercial flight with 100% SAF. Lufthansa now offers an add-on service where customers can choose between insetting (SAF) and offsetting (projects) options in order to make single shipments or long-term contracts CO2-neutral. Although the international aviation industry has set a target of 2% SAF by 2025, the SAF share of total aircraft fuel consumption is currently only 0.01%.
In order to expand the usage of SAF and make aviation more sustainable, the aviation industry has to overcome numerous obstacles. The biggest challenge posed by SAF is the lack of maturity in production methods. When it comes to SAF produced from biomass, it is doubtful whether biogenic feed-stocks can satisfy the expected future demand without compromising food security or land conservation.
The main challenge related to synthetically produced SAF is the gap in production cost when compared with fossil fuel. Although this production method is currently unable to compete with biofuels in terms of costs, it is expected to become the most economically competitive SAF solution in the long term.
In addition, support from governments and international organizations has to take on the role of a catalyst in order to encourage companies to shift their focus from conventional fuels to SAF. Possible approaches could be tax exemptions on SAF, direct funding of relevant projects or the promotion of SAF through legislation.