ABSTRACT

This chapter focuses on understanding how feedstock selection and processing decisions and the entire life cycle of the fuel production process affect the environmental performance of the resulting alternative jet fuels. It assesses the climate impacts of alternative drop-in aviation fuels through the life cycle analysis of associated greenhouse gas emissions. The alternative jet fuel pathways include jet fuel production from petroleum; Fischer-Tropsch technology; hydroprocessed esters and fatty acids from vegetable, waste, and algal oils as well as from animal fats; and biochemical conversion of simple sugars through fermentation and advanced fermentation technologies. The chapter evaluates and compares these pathways with conventional jet fuel production as the reference case. Although one of the primary drivers for alternative fuel production has been the reduction of life cycle greenhouse gas emissions and the associated impacts on the global climate, water use and water quality have been identified as critical concerns relating to the production of biofuels and bioenergy.