Life Cycle emission of selected Sustainable Aviation Fuels – A review

Abstract

Sustainable Aviation Fuels (SAF) are one of the most promising mid-term solution to reduce GHG emission from aviation sector. Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) established a new appellation for SAF, which is CORSIA eligible fuel (CEF). SAF to be considered as CEF should meet much more requirements, which are described in this article, but also should reduce GHG emission at least at 10% compared to conventional aviation fuel. This article focus on Life Cycle Assessment of SAF and CEF and analyzes the life cycle emission factors of CEF harvest from CORSIA document, but also compare that values for HEFA with other researches. Article shows how much important is Land Use Change factor in life cycle emission assessment, which can significantly change the final LCA value. Results from the analyses are that the lowest life cycle emission factor has miscanthus from Fischer-Tropsch conversion process, which is equal to -22.5 gCO2e/MJ, but also from Alcohol to Jet conversion process, which is -10.7 gCO2e/MJ (ATJ based on isobutanol) and -6.8 gCO2e/MJ (ATJ based on ethanol). For HEFA, which is the most used SAF pathway, the lowest life cycle emission factor for CEF has jatropha oil and the value was 10.4 gCO2e/MJ. The results analyzed in the article show also how different life cycle emission factors for the same feedstock and the same pathway could be depending on the cultivation, transport and other stages of feedstock's life cycle.