Advanced biofuel production: A comprehensive techno-economic review of pathways and costs

• Feedstock and pathway selection had the most significant impact on the MPSP. • The feedstock share in MPSP varies among the conversion pathways from 66% to 16%. • Hydrothermal liquefaction had the lowest average MPSP at $4.0/gge. • Among the studied pathways, gasification had the highest CapEx share in MPSP. Despite expectations, the production costs of advanced biofuels, known for their environmental benefits, have not decreased in recent years, even with policy incentives. This review paper examines the techno-economics of advanced biofuel production in the literature, specifically focusing on the impact of various variables on production costs. The analysis reveals that among the studied factors, feedstock and pathway selection have the most significant impact on the minimum product selling price (MPSP) of biofuels. The study determined the MPSP for different pathways, finding that the hydrothermal liquefaction had the lowest average MPSP at $4.0/gge, while the cellulosic ethanol to jet fuels pathway had the highest average MPSP at $5.7/gge. Feedstock costs account for 35% of the total costs, with hydrogenated esters and fatty acids pathway having the highest feedstock share of 66% and hydrothermal liquefaction having the lowest share of 19%. Factors such as conversion yield and energy efficiency also play a crucial role in determining MPSP, with higher yields and energy efficiency leading to reduced costs. The review also highlights the significance of making use of by-products generated during biofuel production to improve the efficiency of processes.