Happs Renee M, Hanes Rebecca J, Bartling Andrew W, Field John L, Harman-Ware Anne E, Clark Robin J, Pendergast Thomas H, Devos Katrien M, Webb Erin G, Missaoui Ali, Xu Yaping, Makaju Shiva, Shrestha Vivek, Mazarei Mitra, Stewart Charles Neal, Millwood Reginald J, Davison Brian H
Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States.
Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, United States.
ACS Sustain Chem Eng. 2024 Jan 22;12(5):1897-1910. doi: 10.1021/acssuschemeng.3c05770. eCollection 2024 Feb 5.
Economically viable production of biobased products and fuels requires high-yielding, high-quality, sustainable process-advantaged crops, developed using bioengineering or advanced breeding approaches. Understanding which crop phenotypic traits have the largest impact on biofuel economics and sustainability outcomes is important for the targeted feedstock crop development. Here, we evaluated biomass yield and cell-wall composition traits across a large natural variant population of switchgrass (.) grown across three common garden sites. Samples from 331 switchgrass genotypes were collected and analyzed for carbohydrate and lignin components. Considering plant survival and biomass after multiple years of growth, we found that 84 of the genotypes analyzed may be suited for commercial production in the southeastern U.S. These genotypes show a range of growth and compositional traits across the population that are apparently independent of each other. We used these data to conduct techno-economic analyses and life cycle assessments evaluating the performance of each switchgrass genotype under a standard cellulosic ethanol process model with pretreatment, added enzymes, and fermentation. We find that switchgrass yield per area is the largest economic driver of the minimum fuel selling price (MSFP), ethanol yield per hectare, global warming potential (GWP), and cumulative energy demand (CED). At any yield, the carbohydrate content is significant but of secondary importance. Water use follows similar trends but has more variability due to an increased dependence on the biorefinery model. Analyses presented here highlight the primary importance of plant yield and the secondary importance of carbohydrate content when selecting a feedstock that is both economical and sustainable.
经济可行的生物基产品和燃料生产需要使用生物工程或先进育种方法培育出高产、优质、具有可持续工艺优势的作物。了解哪些作物表型性状对生物燃料经济性和可持续性结果影响最大，对于有针对性的原料作物开发至关重要。在此，我们评估了在三个共同园地点种植的柳枝稷（.）大型自然变异群体中的生物量产量和细胞壁组成性状。收集了331个柳枝稷基因型的样本，并分析了其碳水化合物和木质素成分。考虑到多年生长后的植物存活率和生物量，我们发现所分析的基因型中有84种可能适合在美国东南部进行商业生产。这些基因型在群体中表现出一系列生长和组成性状，这些性状显然相互独立。我们利用这些数据进行技术经济分析和生命周期评估，在具有预处理、添加酶和发酵的标准纤维素乙醇工艺模型下评估每个柳枝稷基因型的性能。我们发现，单位面积柳枝稷产量是最低燃料销售价格（MSFP）、每公顷乙醇产量、全球变暖潜能值（GWP）和累积能源需求（CED）的最大经济驱动因素。在任何产量水平下，碳水化合物含量都很重要，但次要一些。用水情况遵循类似趋势，但由于对生物精炼厂模型的依赖性增加，其变异性更大。此处的分析突出了在选择经济且可持续的原料时，植物产量的首要重要性以及碳水化合物含量的次要重要性。
