The success of long-term sustainable biofuel production on agricultural lands is still questionable. To this end, we investigated the effects of crop prices on the changes of agricultural land use for biofuel canola production in three wheat crop management zones in North Dakota. The effects of canola hydroprocessed esters and fatty acids (HEFA) production on greenhouse gas (GHG) emissions and energy demand were investigated along with different allocation methods. The Environmental Policy Integrated Climate (EPIC) and Alternative Fuel Transportation Optimization Tool (AFTOT) models were used to simulate the life cycle assessment (LCA) inputs for two key stages of the HEFA pathway: cultivation and transportation. From the EPIC model results, the increase in canola price had a significant impact on predicted farmer decisions to displace food crops with energy crops and particularly on resulting changes in soil carbon (C). The LCA results suggested that to increase soil C sequestration, energy canola should be grown in the place of the fallow whenever possible to guarantee the long-term soil C sustainability of canola HEFA. Other possible ways to mitigate the GHG emissions included using anhydrous ammonia as the nitrogen fertilizer for cultivation and H2 integration (use of HEFA coproducts in H2 production) for HEFA conversion.

Biomass feedstock costs remain one of the largest impediments to biofuel production economics. Municipal solid waste (MSW) represents an attractive feedstock with year-round availability, an established collection infrastructure paid for by waste generators, low cost, and the potential to be blended with higher cost feedstocks to reduce overall feedstock costs. Paper waste, yard waste, and construction and demolition waste (C&D) were examined for their applicability in the pyrolysis conversion pathway. Paper waste consisted of nonrecyclable paper such as mixed low grade paper, food and beverage packaging, kitchen paper wastes and coated paper; yard waste consisted of grass clippings, and C&D wastes consisted of engineered wood products obtained from a construction waste landfill. The waste materials were tested for thermochemical conversion potential using a bench scale fast micropyrolysis process. Bio-oil yields were the highest for the C&D materials and lowest for the paper waste. The C&D wastes had the highest level of lignin derived compounds (phenolic and cyclics), while the paper waste had higher levels of carbohydrate derived compounds (aldehydes, organic acids, ketones, alcohols, and sugars). However, the paper material had higher amounts of lignin derived compounds than expected based upon lignin content that is likely due to the presence of polyphenolic resins used in paper processing. The paper and yard wastes had significantly higher levels of ash content than the C&D wastes (14−15% versus 0.5−1.3%), which further correlated to higher levels of alkali and alkaline earth metals, which are known to reduce the amount of pyrolysis bio-oil produced. The effect of acid washing was evaluated for grass clipping and waste paper, and the amount of bio-oil produced was increased from 58% to 73% and 67% to 73%, respectively.

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Potential land-use change impact has been of concern for producing biomass-derived fuels. To avoid displacing crop production, this study considered north central and western U.S. nonirrigated wheat-growing states for integration of oilseed that fits well into rotations with existing grain crops for renewable jet fuel production. We conducted analyses showing oilseed supply and natural resource impacts based on 2326 9 km × 9 km grid cells in the U.S. Northern Great Plains and further examined the cradle-to-grave environmental impact based on inputs taken from a collection of biogeochemical, hydrological, farmer behavior, and biomass logistics models. Life cycle assessment results from this study show that introducing oilseeds to existing crop rotations for coproduction of food and renewable jet fuel has significant advantages in terms of global-warming potential compared to fossil jet (88 g CO2 eq/MJ), with considerable soil carbon savings from replacing the fallow period. The greenhouse gas emissions can be as low as −235 to −349 g CO2eq per MJ of jet fuel using displacement allocation, and −55 to −107 g CO2eq per MJ jet fuel using energy allocation, over the price points from $400 to $800 per Mg of rapeseed. Total net revenue from this land transition also creates opportunities to boost fuel oilseeds production and farmer incomes.

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