Aviation will require low carbon liquid fuel to decarbonise, as battery powered passenger aircraft will not be viable for decades. Europe, in its RefuelEU proposal, is focussing on sustainable aviation fuels (SAF) made from biogenic wastes or carbon dioxide removed from the air, and excluding all crop derived aviation fuels. But it is tenable to block even biofuels from crops that have been approved as sustainable by other EU regulation? BP is certainly backing them. It recently announced a tie-up with Nuseed to promote Carinata, an oil seed plant that can be grown as an intermediate crop, without requiring more land.
ReFuelEU will apply to all operators flying from EU airports., with measures to avoid ‘tankering’ or using fuel from elsewhere to fly from EU airports. The oil companies will be responsible for blending the required levels of sustainable aviation fuel (SAF). These companies are proceeding cautiously. Most oil majors are focussing on waste oils, particularly used cooking oil. Oil seeds from crops and waste oils are the lowest risk options for that highest risk of all transport fuels, aviation kerosene. The processing technology is straight forward, and it has already been though the long and costly approval process. BP, Shell and the others have the muscle to secure their supplies of raw materials and the global reach to match the type of sustainable aviation fuel with the local regulation. ICAO has already approved carinata as a source of low carbon aviation fuel so BP will have an outlet for its fuel in airports worldwide even if the EU does not accept it.
Less mature technologies, namely Fischer-Tropsch and alcohol-to-jet have also been approved and they could be applied to the agricultural, forestry and municipal wastes authorised by the EU. However, all of these materials are limited by the demand for the main product. When there is a strong commercial incentive from a blending mandate, the situation could arise where the waste or residue achieves a higher price than the main product, leading to unsustainable practices or even fraudulent behaviour. Used cooking oil has on occasions, had a value greater than that of virgin palm oil. So, wastes have their own problems, and they will only ever be part of the solution.
Europe has aspirations for synthetic fuel made from renewable hydrogen and carbon dioxide removed from the air, with RefuelEU proposing a blending mandate for these fuels of 0.75% in 2030 rising to 28% by 2050. This would need a huge investment in processing facilities, not to mention renewable energy generation, hydrogen production and carbon dioxide abstraction. Set against the precedent of unhelpful changes in European policy towards biofuels and reducing support for renewables, such investments are likely to be regarded as commercially high risk by the companies that must make them. The technology also needs to be proved on a commercial scale.
SAF from intermediate crops with established sustainability credentials, on the other hand, will be much easier to implement. Nuseed carinata, for instance, has obtained an EU approved sustainability certification. Furthermore, the Renewable Energy Directive (RED II) already recognises intermediate crops as separate from food and feed crops and therefore acceptable as raw materials for biofuels provided that the intermediate crop does not trigger demand for additional land. These crops would also give farmers an additional income. It is true that, they may require additional water and fertiliser but these are variables which can be overseen by certification.
RED II also authorises ‘low indirect land-use change-risk biofuels’ produced from crops which result from better agricultural practices or from degraded or unused land. These low ILUC feedstocks would allow farmers in areas with excess agricultural land or poor yields to benefit.
In reality, all types of SAF will be needed to bring about meaningful decarbonisation of aviation. But with so many restrictions on raw materials, SAF in Europe is in danger of getting stuck at the departure gate.
Published: 10 February 22
