US SAF Producers Target Net Zero in Drive to Reduce the Carbon Intensity of Their Fuels

by Susan van Dyk (GreenAir Online) The recent virtual symposium hosted in the US by CAAFI, the Commercial Aviation Alternative Fuels Initiative, illustrated the increasing momentum in sustainable aviation fuel (SAF) commercial development, with companies at different stages of development outlining ambitious plans for multiple facilities over the coming years. Many facilities are already under construction or nearing completion, and the increased availability of SAF is expected to become a reality over the next few years. Significantly, many producers are pursuing net zero SAF from initial construction by integrating technologies such as renewable energy, green hydrogen and carbon capture and storage into their fuel production strategy, reports Susan van Dyk. By incorporating net zero targets as part of the initial engineering design of a facility, any SAF pathway can potentially be net zero if the right policies are in place to incentivise the greatest emission reductions.

Gevo’s first fully net zero project is planned for its Lake Preston, South Dakota, facility and across its entire feedstock supply chain, CEO Pat Gruber told the symposium. Onsite electricity used in the facility will be derived from biogas, offsite electricity from wind turbines and renewable hydrogen. As Gevo uses corn for the production of isobutanol, the feedstock supply chain is addressed explicitly through better agricultural practices and land management, improved tillage practices and sustainable fertiliser. Gevo works closely with farmers and plans to reward them according to the sustainability of their corn, according to Gruber.

Eric McAfee, CEO of Aemetis, told the CAAFI symposium the company’s strategy for net-zero includes renewable natural gas, cellulosic hydrogen, and carbon capture and storage. The proposed facility of SkyNRG Americas aims for maximum emission reductions by producing hydrogen from electrolysis, stated CEO John Plaza, while Red Rock Biofuels is implementing engineering changes to its Lakeview facility to lower the carbon intensity of the fuels. According to CEO Terry Kulesa, the Lakeview facility will use solar power for electricity and undertake carbon capture of any emissions.

Proponents of synthetic e-fuels, such as Andrew Murphy from Transport and Environment, argue that power-to-liquid (PtL) fuels should be the main SAF technology in the long term as it is the only pathway that can achieve net zero. In contrast, Andreea Moyes, Global Aviation Sustainability Director at BP in a presentation at the CAAFI Symposium, argues “multiple SAF pathways are required, and all should be allowed to compete on their own merits within societal preference.” According to Moyes, the GHG profile of SAF, rather than the volume, should be the focus.

An important driver for aggressive targeting of maximum emissions reductions is placing a value on carbon. This type of policy is already in action in California’s Low Carbon Fuel Standard and has created a strong incentive for low carbon intensity fuels. The proposed Sustainable Skies Act, recently introduced in the US House of Representatives by Congressman Brad Schneider, creates exactly this type of policy in the aviation sector (see article). The Act proposes a blenders tax credit of $1.50 per gallon of SAF that provides a 50% reduction in emissions. SAF that provides greater emission reductions can earn an additional credit of $0.01 per gallon for each percentage the fuel reduces emissions over 50% up to a maximum of $2 per gallon for a 100% reduction, in order to incentivise greater reductions in emissions.

In contrast, the European ReFuelEU Aviatio n policy proposes a volumetric blending mandate which is not directly linked to emission reductions (see article). Although this will create a strong demand signal, it seems unlikely to drive aggressive carbon reductions of SAFs. READ MORE