Influence of upstream, distributed biomass-densifying technologies on the economics of biofuel production.

• For most scenarios, densifying biomass does not improve the economics. • Densification is economically advantageous when there is a high feedstock competition. • The plant size of a densification facility has a minimal impact on the overall economics. Biomass such as switchgrass can be converted to renewable gasoline and diesel (RGD) fuels via integrated fast pyrolysis and hydrodeoxygenation. However, the low bulk density of biomass feedstocks produces relatively high transportation costs, driven by the large volumes needed to supply biorefineries. Densification can reduce transportation volumes, and therefore transportation costs for bioenergy production. However, the additional costs of biomass densification, along with decreases in overall mass and energy yields, influence the overall economic performance of RGD production. This study investigated the techno-economic impacts of pelletizing, torrefying, or pyrolyzing the biomass at distributed facilities prior to upgrading the intermediates to RGD at a centralized facility. Eight scenarios were considered. When there is no feedstock competition, biomass densification at the distributed facility was shown to reduce the transportation cost by 20%–50%. However, the capital and operating costs required for densifying biomass increased the total cost of RGD production by 3%–35% compared to RGD made from non-densified biomass. The cost of making RGD from densified biomass was only reduced below the cost of making RGD from non-densified biomass for the case when the fraction of land surrounding the biorefinery facility allocated to the biomass cultivation is less than 0.25. This finding is attributed to the high cost of transporting non-densified biomass from a larger procurement radius. Sensitivity analysis indicated that RGD fuel yield, densification costs, project investment, and the rate of return all have significant impacts on the overall economics of RGD production. [ABSTRACT FROM AUTHOR]