Frequently asked questions concerning Sustainable Aviation Fuel (SAF)

SAF is the generic term used for all aviation fuels that are produced without the use of fossil resources 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 sources. The current generation of SAF used by the Lufthansa Group is produced from biogenic residues, such as used cooking oils and waste fats.

Infographic: What is Sustainable Aviation Fuel (SAF)

The combustion of SAF and fossil kerosene produces identical amounts of CO2. However, in the case of SAF, biogenic residues (e.g. used cooking oil) are used for production, which have previously removed CO2 from the atmosphere. Consequently, when SAF is burned, only as much CO2 is emitted as was previously removed from the atmosphere by the feedstock. As the production processes and the transportation of SAF currently still generates fossil CO2, SAF does not completely reduce CO2 emissions by 100% across the entire supply chain compared to fossil kerosene.
However, the Lufthansa Group guarantees that their currently used SAF reduces CO2 emissions by at least 80% compared to fossil kerosene.

The SAF currently used by the Lufthansa Group is produced in the HEFA process (Hydro processed Esters & Fatty Acids) from biogenic residues such as used cooking oils. It guarantees a CO2 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 future-oriented technologies include Power-to-Liquid (PtL) and Sun-to-Liquid (StL) processes, which rely on renewable electricity or solar heat as energy sources.

The Lufthansa Group sources SAF 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 airports in Europe where the Lufthansa Group uplifts large quantities of kerosene.

Yes, Lufthansa Group passengers can already offset the calculated CO2 emissions of their individual air travel through the use of SAF in combination with a contribution to the high-quality climate project portfolio. This option can be selected and purchased directly during the booking process. In addition, Lufthansa Group offers Green Fares, a fare option with a fixed SAF component.

By booking an option for more sustainable flying with SAF and a contribution to the high-quality climate project portfolio, Lufthansa Group procures the amount of SAF required to achieve the desired partial CO2 offset and feed it into its flight operations within six months. 

No, due to the remaining CO2 emissions from production 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, booking an option for more sustainable flying does not lead to an individual SAF uplift on the booked flight. It supports the general use of SAF within Lufthansa Group's route network. What’s essential is that the SAF is used within the Lufthansa Group’s flight operations, ensuring the CO2 reduction. The Lufthansa Group guarantees that the SAF will be fed into its flight operations within six months of the passenger’s flight departure.

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

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

For a flight, an algorithm determines the amount of CO2 per passenger based on the booking class and aircraft type. For the calculated amount, passengers can contribute to a high-quality climate project portfolio in combination with the use of SAF. The price premium for SAF to the customer is primarily based on the prevailing market procurement costs.

The current amount of SAF available globally remains extremely small. By the end of 2024, only around 0.3 per cent (=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 tons of SAF, which accounted for around 0.2 per cent of the Group’s total fuel demand. Over the coming years, the Lufthansa Group intends to successively increase this amount. The Lufthansa Group ensures that customer demand for SAF can be met. However, the aviation industry cannot initiate a self-sustaining market on its own.

The price of SAF depends on technology and 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 only available in very small quantities and still up to ten times more expensive than fossil kerosene. The Lufthansa Group is involved in various projects to ensure that sustainable aviation fuels become available in larger quantities as quickly as possible.

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, however, they are considered promising from an environmental and scaling perspective.

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.