CAAFCER study confirms reduced contrail formation when flying on SAF

Renco BeunisLast year SkyNRG supplied sustainable aviation fuel (SAF) for the Civil Aviation Alternate Fuel Contrail and Emissions Research (CAAFCER) study in Canada. The report was published early 2018 and Renco Beunis, Operations Manager at SkyNRG who worked on this project, shares his insights about the study.

What is CAAFCER and what was SkyNRG’s role in this project?
CAAFCER is a Canadian project initiated by the Green Aviation Research and Development Network (GARDN), that studies contrail formation from commercial flights. The study compared contrail properties of flights between Montreal and Toronto, part of the flights was powered by a 43% HEFA blend, the others by fossil jet fuel. Project partners were Air Canada, The Waterfall Group, The University of Alberta, The Boeing Company, the National Research Council (NRC) and SkyNRG. SkyNRG set up the SAF supply chain for which we arranged the HEFA sourcing at AltAir Fuels, the logistics to Canada, the local blending with fossil jet fuel in cooperation with Air Canada and the supply at Montreal Airport.

What are the most important conclusions in the report and why are they relevant for the aviation industry?
There are three key takeaways from the study:
• HEFA based SAF is expected to generate fewer contrail particles due to having a higher hydrogen content and reduced sulphur content compared to fossil jet fuel
• The volume of the contrail particles is smaller for flights powered by HEFA based SAF
• The size of the SAF contrails was approximately 10% smaller than for flights on fossil jet fuel
The study is relevant for the aviation industry since contrails, leading to contrail-cirrus formation, are important contributors to radiative forcing. They are considered to have an equally negative impact on the climate as CO2 emissions from aviation. This study confirms that flying on SAF has additional benefits other than CO2 emission savings, further reducing the aviation’s impact on global warming.

What are the next steps in the project?
Though this study has been completed, further research on contrail formation and its properties is needed. NRC, for example, wants to install probes on their trace plane to measure the extinction coefficient of all ice particles. Also, radiation studies are needed to quantify the reduction in radiative forcing.

Download the full report here