A regional life cycle assessment and economic analysis of camelina biodiesel production in the Pacific Northwestern US

摘要

The primary goal of this study was to model the soil emissions during camelina and wheat production in a three-year cycle in the Pacific North West region of the United States considering spatial variations in agro-climatic factors. The second goal of this study was to evaluate the effect of regional agro-climatic variations on the life cycle impact of biofuel production from camelina. DNDC (Denitrification-Decomposition) model was used to estimate the soil emissions in different regions, and openLCA software was used to quantify the environmental impacts of camelina biodiesel production in the State of Oregon. The suitable lands for the cropping system were lands with winter wheat-fallow cropping system and rainfall of 20-40 cm. The model was run for 60 years to reach to the soil organic carbon (SOC) equilibrium point. The results from the cycle with the SOC equilibrium were used to conduct life cycle assessment (LCA). Energy allocation method was selected to allocate LCA results based on the energy content of products and co-products. The results showed that the global warming potential of camelina biodiesel produced under two scenarios was significantly different (P-value 0.01) such that no-tillage practice had lower GHG emissions compared to conventional tillage system. Uncertainty analysis was carried out using Monte Carlo method, and the results showed that there could be up to 23% variation in soil emissions due to variation in air temperature and SOC. The break-even cost for a three-year crop rotation (winter wheat-fallow-camelina) was estimated to be 1715 $/ha/3y; therefore, locations with income equal or more than the break-even cost and low environmental impacts are suitable for the winter wheat-fallow-camelina rotation system. (C) 2017 Elsevier Ltd. All rights reserved.