Frequently asked questions about Sustainable Aviation Fuel (SAF)

SAF is the generic term used for all aviation fuels that are produced without the use of fossil raw materials such as crude oil or natural gas. SAF is a key technology for making air travel more sustainable and is essential for the energy transition in aviation. Various manufacturing processes and different feedstocks are available as energy source. The current generation of SAF used by the Lufthansa Group is mainly produced from biogenic residues, such as used cooking oils and waste fats.

Although the combustion of SAF and fossil kerosene produces identical amounts of CO₂ , the use of SAF creates a CO₂ cycle: Biogenic residues (e.g. used cooking oil) are used for production, which have previously extracted CO₂ from the atmosphere. Consequently, when SAF is burned, only as much CO₂ is emitted as was previously removed from the atmosphere by the starting materials. Since fossil CO₂ is currently still generated in the manufacturing and supply process of SAF, SAF reduces CO₂ emissions by approximately 80% rather than 100% when compared to fossil kerosene over the entire lifecycle.

The SAF currently used by the Lufthansa Group is produced in the HEFA process (Hydroprocessed Esters & Fatty Acids) from biogenic residues such as used cooking oils. It guarantees a greenhouse gas reduction of at least 80% compared to fossil kerosene.

SAF plays a central role in achieving the goal of CO₂-neutral aviation by 2050. The Lufthansa Group has been actively involved in SAF research for many years and is driving forward the introduction of next-generation sustainable aviation fuels. Examples of such forward-looking technologies include Power-to-Liquid (PtL) and Sun-to-Liquid (StL) technologies, which rely on renewable electricity or solar heat as energy sources.

The Lufthansa Group sources SAF almost exclusively from established suppliers in Europe. The SAF is purchased by the Lufthansa Group’s fuel management department, blended with fossil kerosene by the supplier, and then physically transported to the airports where the Lufthansa Group uplifts large quantities of kerosene. 

Yes, Lufthansa Group passengers can already reduce the CO₂ emissions of their individual air travel with SAF by calculation. This option can be selected and purchased directly during the booking process. In addition, the Green Fares include a fare option with a fixed SAF component. 

When a passenger books a SAF option, the Lufthansa Group procures the amount of SAF required to achieve the desired CO₂ reduction, if SAF is not already in stock, and feeds it into its flight operations within six months.

No, due to the remaining CO₂ emissions from manufacturing and transportation of SAF, current SAF technologies cannot reduce 100% of a flight’s emissions. However, the Lufthansa Group currently uses SAF that reduces emissions by at least 80% compared to fossil kerosene.

No, it cannot be guaranteed that the SAF molecules will be used to fuel the passenger’s specific aircraft. After being procured by the Lufthansa Group, SAF is blended with conventional kerosene by the supplier and then transported to various airports for use. What matters most is that the SAF is used within the Lufthansa Group’s flight operations, thereby realising the CO₂ savings. The Lufthansa Group guarantees that the SAF will be fed into its flight operations within six months of the passenger’s flight.

No, SAF which is part of the Lufthansa Group’s offers for customers is purchased in addition to existing SAF mandates and is fed into the Group’s flight operations within six months of the respective flight.

The Lufthansa Group calculates the surcharge incurred to replace fossil kerosene with SAF for an individual flight. 

For a flight, an algorithm determines an amount of CO₂ per passenger based on the booking class and aircraft type. This amount can either be offset by supporting climate projects and/or reduced by using SAF. The surcharge for SAF to the customer is primarily based on the prevailing market procurement costs. The Lufthansa Group actively takes advantage of favorable market conditions to procure SAF of the best possible quality at competitive prices.

The current amount of SAF available globally remains extremely small. By the end of 2024, only around 0.3% (=1,000,000 tonnes) of the global fuel demand is of non-fossil origin. This is not sufficient to enable large-scale use of SAF in flight operations. In 2024, the Lufthansa Group used around 20,000 tonnes of SAF, which accounted for 0.2% of the Group’s total fuel demand. Over the coming years, the Lufthansa Group intends to successively increase this amount. Even now, the Lufthansa Group ensures that customer demand for SAF can be met.

The price of SAF depends on the technology and the oil price development. Currently, the market price for existing SAF from biogenic residues is three to five times higher than the price for fossil kerosene. Next-generation SAF is currently still up to ten times more expensive than fossil kerosene. The Lufthansa Group is involved in numerous projects to ensure that sustainable aviation fuels become available in larger quantities as quickly as possible. If production becomes more industrialised, the price of SAF is expected to decrease.

Electricity-based fuels, known as Power-to-Liquid (PtL) or “eFuels”, also fall under the category of sustainable aviation fuels. This next generation of SAF is produced using renewable electricity, water and CO₂ (taken from the atmosphere) to create a synthetic crude oil, which can be processed into kerosene. PtL aviation fuels are still under development towards industrial-scale production but are considered as an important step towards CO₂-neutral flying in the long term.

In Sun-to-Liquid (StL) technology, high-temperature solar heat, water, and CO₂ (taken from the atmosphere) are used to produce a synthesis gas, which can then be converted into liquid fuel such as kerosene using standard industrial processes. Such StL fuel closes the CO₂ cycle, as it releases only as much CO₂ when it is combusted as was previously used in its production. The Lufthansa Group is driving the development of this technology and cooperates with Swiss solar fuel pioneer Synhelion.