(64d) Techno-Economic Feasibility of Miscanthus as Biomass Feedstock: Analysis Using BioFeed Model

Miscanthus has been proposed as a potentially important biomass feedstock option for the emerging biorefinery industry owing to its various desirable properties. However, very little information about its sustainable production as well as its techno-economic feasibility exists at this stage. The objective of this work is to explore these issues through the application of an optimization modeling framework. BioFeed is a system level optimization model which has been developed to study and optimize various feedstock production and provision activities at a regional scale. It has been successfully applied in the past to study switchgrass production. The work will initially discuss a number of recent enhancements to the BioFeed model that enable modeling and optimization of production activities in greater details. New biomass packing, size reduction and pre-processing operations such as grinding and pelletization have been added. Pre-processing at shared centralized facilities instead of individual farms is also modeled. Biomass handling and in-field transportation activities have been modeled in greater details. The new version of the model is then applied to study Miscanthus production in southern Illinois. Various current and near term technologies are evaluated and compared, and important operations in the supply-chain are identified. Then, sensitivity analysis is carried out to identify potentially beneficial technological developments, thereby identifying important research areas. Two different supply regimes of Miscanthus, namely, distributed storage and processing, and centralized storage and processing, are evaluated. The impact of modifying the harvesting window is also quantified. The results show that the collection, harvest, storage and transportation (CHST) cost of Miscanthus is about 45 $/Mg based on the current equipment availability. Grinding of biomass at farms is beneficial only if low-cost storage facilities are available at farms. Major cost reduction can be achieved through the use of integrated, single-pass mowing and baling, as well as modification of the harvesting window. If the refinery requires a uniform form and quality of biomass, implementation of pre-processing at a centralized facility hold potential. Although this system configuration increases the total cost, it reduces the cost borne by farms. In all these scenarios, BioFeed results give the operational blueprint in addition to the design configuration, which is a unique feature of the modeling framework. The results have important implications on the quality and form of biomass being delivered at the biorefinery.