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The selection of locations and practices for energy crops requires the economics to be planned and the carbon intensity of the fuel to be assessed. This study develops a framework for selecting near‐optimal cropland sites to minimize the cost to produce a targeted quantity of an energy crop, considering soil properties, fertilizer management, and spatio‐temporal trends in crop yield and soil emissions. DayCent, a biogeochemical model, simulates site‐level crop yield, and soil emissions. As a case study, this framework is applied to a 2.08 × 108 L year−1 capacity barley‐to‐ethanol biorefinery that selects cultivation sites from winter fallow cropland in the mid‐Atlantic region of the USA. The framework implements carbon crediting as per California's Low Carbon Fuel Standard. Our analysis finds the biorefinery's strategy on co‐products significantly influences its life‐cycle carbon intensity ranging between 0.74 gCO2e MJ−1 for all co‐product use and 59 gCO2e MJ−1 for no co‐product use. Coastal counties in Delaware show low soil emission and high yield, but higher transportation distances increase the carbon intensity of these distant croplands. When co‐products are used, the least intensive fertilizer management with fertilizer applications in spring is identified as the cost‐optimized choice for the biorefinery. It is also the option economically favored by growers, suggesting that detailed monitoring of these practices might not be needed to assure the adoption of low‐emission cultivation practices. However, the framework might demonstrate different results for other biofuel‐crop scenarios or different locations. The framework presented can assess the performance of a biorefinery prospectively and improve investors' confidence in the biofuel industry. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Debates surrounding the greenhouse gas (GHG) emissions from land use of biofuels production have created a need to quantify the relative land use GHG intensity of fossil fuels. When contrasting land use GHG intensity of fossil fuel and biofuel production, it is the energy yield that greatly distinguishes the two. Although emissions released from land disturbed by fossil fuels can be comparable or higher than biofuels, the energy yield of oil production is typically 2-3 orders of magnitude higher, (0.33-2.6, 0.61-1.2, and 2.2-5.1 PJ/ha) for conventional oil production, oil sands surface mining, and in situ production, respectively). We found that land use contributes small portions of GHGs to lifecycle emissions of California crude and in situ oil sands production (<0.4% or <0.4 gCO2e/MJ crude refinery feedstock) and small to modest portions for Alberta conventional oil (0.1-4% or 0.1-3.4 gCO2e/MJ) and surface mining of oil sands (0.9-11% or 0.8-10.2 gCO2e/MJ). Our estimates are based on assumptions aggregated over large spatial and temporal scales and assuming 100% reclamation. Values on finer spatial and temporal scales that are relevant to policy targets need to account for site-specific information, the baseline natural and anthropogenic disturbance. [ABSTRACT FROM AUTHOR]