Energy-based break-even distance transportation distance of biomass feedstocks

Authors: Tumuluru, Jaya Shankar; IGATHINATHANE, C - North Dakota State University; Archer, David; MCCULLOCH, RICHARD - Idaho National Laboratory

Submitted to: Frontiers in Energy Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/26/2024
Publication Date: 4/1/2024
Citation: Tumuluru, J., Igathinathane, C., Archer, D.W., Mcculloch, R. 2024. Energy-based break-even distance transportation distance of biomass feedstocks. Frontiers in Energy Research. 12. https://doi.org/10.3389/fenrg.2024.1347581.
DOI: https://doi.org/10.3389/fenrg.2024.1347581

Interpretive Summary: Biomass is the largest provider of renewable energy in the U.S., and could become an even more significant domestic energy source. However, one concern is whether more energy is used in transporting the biomass than the energy it contains. To analyze the energy use in transporting biomass compared to its energy content, a break-even distance was calculated for different types of biomass transported by truck, rail, and ship. The break-even distance is the distance that biomass can be transported utilizing the total amount of energy contained in the biomass. Results showed that torrefied biomass pellets had the highest break-even distance for each transportation method. Results also show that ship transport was most efficient, followed by rail and truck. Transporting biomass by truck, the break-even distance ranged from 0.9 to 2.88 times the U.S. perimeter, depending on biomass type. So, the energy used in transporting biomass does not, by itself, limit where it can be transported for biorefining. This research is important for bioenergy producers and policy makers in understanding how different biomass sources and transport methods affect net energy production.

Technical Abstract: The distance a solid biomass feedstock could be used to transport the feedstock when used as biobased fuel is critical information for transportation analysis. However, this information is not available. The break-even transportation distance (BTD) of various fuels from biomass feedstocks and fossil sources was analyzed for truck, rail, and ship transport modes based on bulk density, moisture content, and specific energy. Fourteen different biomass feedstocks, such as crop residues (e.g., corn stover), woody biomass (e.g., wood chips), including thermally pretreated (torrefied) and densified forms (pellets), cattle feedlot compost, and three standard fossil fuels, namely, coal, lignite, and diesel, were considered for BTD analysis and comparison. The BTD values were derived by comparing the energy content of biomass feedstocks with the energy expended in transporting the fuels through selected transportation modes. For ready reference, an alternative derivation of BTD equations and example calculations were also presented. Among the biomass feedstocks, torrefied pellets had the highest BTD (4.16 × 104 , 12.47 × 104 , and 54.14 × 104 km), and cattle feedlot compost had the lowest BTD (1.29 × 104 , 3.88 × 104 , and 9.23 × 104 km), respectively, for truck, rail, and ship. Higher bulk density and higher specific energy of the biomass feedstocks increased the BTD for all modes of transport. Transport is most efficient when mass-limited. Biomass feedstock bulk densities where transportation becomes mass-limited are 223, 1,480, and 656 kg/m3 for truck, rail, and ship, respectively. Truck transport is typically mass-limited (payload limit restriction; increased BTD), whereas rail transport is entirely volume-limited (cargo space restriction; decreased BTD), and ship transport is mostly volume-limited for biomass feedstocks and masslimited for densified biomass feedstocks. Ship transport is the most efficient, followed by rail and truck; on average for the materials (17) studied, rail is 3.1 times and ship is 9.2 times the truck’s BTD. Based on the bulk density and higher specific energy of the biomass feedstocks, regardless of the refinery location, interstate truck transport of these feedstocks is not a limiting factor in the bio-refining process with the studied biomass feedstock BTD per truckload representing between 0.89 and 2.88 times the U.S. perimeter.