SAF is essential: it has to be SAF-e & Sure !
While, a lot has been said and propagated on the dire need to decarbonise aviation sector, one of the important component to achieve it is the alternate fuels including electric aircraft. Since electric aircraft and H2 fuel cell aircraft are a work in progress; the way forward initially is on SAF-Sustainable Aviation Fuel. Most airlines and the governments have set before them the Net-Zero Emission year as 2050. The extent of emissions on account of aviation are approximately 3% likely to rise to 3.5% by 2030.
R&D in Sustainable Fuels & SAFE Standards
Considerable research and development has gone for the past decade and SAF is considered safe since it conforms to the same chemical constitution as the Jet Fuel. But its production has to ensure highest standards and compliance to ASTM D1655 norms as for Jet fuel. Since, SAF is produced from different raw bio-feedstocks, its blending needs constant risk assessment and strict adherence to processing standards.
Compatibility of Fuels; ICE and Aircraft Engines
In case of ICE engines used in automobiles bio-fuel ethanol in 10-20-30 per cent targets have been drawn globally, but there have been some concerns due to fuel-engine suitability mismatch. Alternate fuels in automobiles showed deteriorating effect on engine performance characteristics, speed and mileage. Therefore, research on long term impact of a particular variant of SAF is extremely important in case of aircraft engines.
Aircraft engines are highly sophisticated, high cost and the most important equipment ensuring take off-fly-land back flawlessly on endless flights. SAF usage should not alter an iota of aircraft engines’ performance as these are critical for safety of aircraft operation.
Feasibility of Adequate SAF Production & Cost Considerations
Secondly, we have to ensure enough production of SAF as airlines cannot keep switching between ATF-SAF-ATF. As per industry reports while Australian airlines were keen to introduce SAF usage, a supply chain is yet to develop. It needs scaling the production to meet gargantuan needs of aviation sector with over 370,00,000 flights in 2024 and approximately 35,000 commercial aircraft currently in service.
With SAF production in 2024 @ 1.3 bn ltrs (1 million tons), double of 2023, interim target of ICAO is to achieve a 5% reduction in carbon emissions using SAF by 2030. The total fuel used by aviation in 2024 is approximately 99 billion gallons which shows infancy of the SAF.
The above data reveals, SAF production is still scant and not wide spread. Production is only to meet about 0.53% of global demand but the estimation of cost is said to be approx. $3.75 billion. That reflects an additional $2.4 billion against the same quantity of jet fuel. Besides, CORSIA-Carbon offsetting and reduction scheme for international civil aviation – related costs were estimated in 2024 an additional $600 million.
As per IATA data, current non-fuel cost and expenses have been well-under airline control. Since 2023 non-fuel unit costs have remained constant @39 cents per ATK-available tonne kilometers. Therefore, commercial considerations for airlines are far reaching too especially in view of additional costs involved in production and logistics of SAF coupled with cut throat competition of aviation industry.
Conclusion
Industry CO2 emissions from aviation are expected to be 935 million tonnes from consumption of 99 billion gallons of fuel during 2024. While Sustainable Aviation Fuel (SAF) is an important leverage for decarbonisation timeline 2050, looking at the miniscule SAF production; it is also true that SAF alone isn’t enough.
We need more than SAF including proactive policies, constant R&D in alternative fuel technology; derive parity between jet fuel and SAF production cost; constant availability; and mandated off-take of the SAF products. The race, surely would be on for the next 25 years when we can see maximum shift from fossil to SAF aviation fuel.
Question :
Your take on the decarbonisation of Aviation, SAF & other considerations?
Prof Dinesh Kumar, MBA, IAP
