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The refereed literature contains few studies that analyze life cycle assessment (LCA) and techno-economic analysis (TEA) methodologies together for lignocellulosic bioenergy systems, using a stochastic modeling approach. This study seeks to address this gap by developing an integrated framework to quantify the environmental and financial impacts of producing and delivering shrub willow in the Northeastern United States. This study analyses four different scenarios from a combination of two different initial land cover types (grassland, cropland) prior to willow establishment, and two harvesting conditions (leaf-on, leaf-off). Monte Carlo simulations were performed to quantify the uncertainty of the results based on a range of financial, logistical, and biophysical variable input parameters (e.g., land rental rates, transportation distance, biomass yield, etc.). Growing willow biomass on croplands resulted in net negative GHG emissions for both leaf on and leaf off scenarios for the baseline. The GHG emissions were lowest for the leaf-off harvest on cropland (−172.50 kg CO2eq Mg−1); this scenario also had the lowest MSP ($76.41 Mg−1). The baseline grassland scenario with leaf-on harvest, results in the highest net GHG emissions (44.83 kg CO2eq Mg−1) and greatest MSP ($92.97 Mg−1). The results of this analysis provide the bioenergy field and other interested stakeholders with both environmental and financial trade-offs of willow biomass to permit informed decisions about the future expansion of willow fields in the landscape, which have the potential to contribute to GHG reduction targets and conversion into fuels, energy, or bioproducts for carbon sequestration and financial benefits. [ABSTRACT FROM AUTHOR]

Abstract Bulk density is a key attribute of biomass feedstocks that affects both conversion processes and logistics. Reported bulk density for fresh willow chips ranges between 195 and 393 kg m−3 and it is unknown if standardized methods using several kg of chips scale effectively to collection vehicles that contain several Mg. The objective of this study was to compare three bulk density methods for 53 commercially harvested willow loads and compare bulk density in three different collection wagons. An ISO standard 'bucket' method was compared to actual and effective bulk density measurements. Mean as-received bulk density using the standard ISO method was 262 kg m−3 (σ = 25) and was not correlated with wagon load measurements of actual or effective bulk density. The actual bulk density in a small (10 m3) collection vehicle was 302 kg m−3 (σ = 32), which was significantly greater than the 214 kg m−3 (σ = 28) that was measured in two larger (30 m3) collection vehicles. In addition, actual bulk density in wagons was higher than the effective bulk density (247 kg m−3 (σ = 24)) observed for the truck deliveries. Collection wagon geometry and design impacted these results, which may have implications for modeling these systems. The variation in bulk density values is important to understand and represent in modeling of harvesting and logistics systems in order to capture what is actually occurring in commercial scale operations. Highlights • Bulk density (BD) values available in the literature cover a wide range. • BD of shrub willow biomass was determined using three methods. • BD measured in commercial wagons did not match BD values from standardized methods. • Willow BD in collection wagons was influenced by size and geometry of dump bodies. • Effective BD may be an adequate surrogate for actual BD in commercial vehicles. [ABSTRACT FROM AUTHOR]