EVALUATION OF LIFE CYCLE GREENHOUSE GAS EMISSIONS OF CHLORELLA-DERIVED JET FUEL BY AUTOTROPHIC CULTURE

Abstract

 Sustainable aviation fuels (SAF) are expected to be introduced to achieve carbon neutrality, but SAF derived from waste residues alone is not sufficient to meet the demand. Microalgae-derived SAF is expected to be a promising source, but its life-cycle greenhouse gas (GHG) emissions are unknown. In this study, the lifecycle GHG emissions of microalgae-derived bio-kerosene (the main component of aviation fuel) were evaluated for the first time. The results showed that recovery by flocculation and extraction using hexane as a solvent after crushing reduced GHG emissions. GHG emissions would be 447.06 kgCO_2e/MJ if CO₂ were produced from fossil fuels, but 140.13 kgCO_2e/MJ if GHG-free CO₂ were available from large-scale emission sources. Furthermore, under the 2030 power supply mix, GHG emissions were found to be 42.63 kgCO_2e/MJ, half the GHG emissions of kerosene from petroleum sources.