Ingrid K. Busch

Opportunities and challenges in the design and analysis of biomass supply chains.

The biomass supply chain is one of the most critical elements of large-scale bioenergy production and in many cases a key barrier for procuring initial funding for new developments on specific energy crops. Most productions rely on complex transforming chains linked to feed and food markets. The term ‘supply chain’ covers various aspects from cultivation and harvesting of the biomass, to treatment, transportation, and storage. After energy conversion, the product must be delivered to final consumption, whether it is in the form of electricity, heat, or more tangible products, such as pellets and biofuels. Effective supply chains are of utmost importance for bioenergy production, as biomass tends to possess challenging seasonal production cycles and low mass, energy and bulk densities. Additionally, the demand for final products is often also dispersed, further complicating the supply chain. The goal of this paper is to introduce key components of biomass supply chains, examples of related modeling applications, and if/how they address aspects related to environmental metrics and management. The paper will introduce a concept of integrated supply systems for sustainable biomass trade and the factors influencing the bioenergy supply chain landscape, including models that can be used to investigate the factors. The paper will also cover various aspects of transportation logistics, ranging from alternative modal and multi-modal alternatives to introduction of support tools for transportation analysis. Finally gaps and challenges in supply chain research are identified and used to outline research recommendations for the future direction in this area of study.

Future Utilization and Optimal Investment Strategy for Inland Waterways: New Model from U.S. Army Corps of Engineers to Assist Policy Makers

For nearly three decades, the U.S. Army Corps of Engineers (the Corps) has been measuring incremental system navigation transportation costs for proposed infrastructure investments in search of the National Economic Development (NED) plan: local optimization in a system-level evaluation. The increasingly complex and sophisticated analysis requires the development of additional modeling modules. The traditional analysis assumed a most-likely traffic forecast and a set investment timing. Cost-benefit analyses on various alternatives were compared to determine the without-project condition and the recommended with-project NED plan. Sensitivity analyses of traffic forecasts and investment timing were done on the with-project plan. The second generation of analysis factored in the impacts of scheduled chamber closure differences between alternatives, and the third generation of analysis factored in the impacts of unscheduled ones. The goal is to be able to optimize investments simultaneously across a system (not just investments at one site) under a series of forecast scenarios while capturing structural reliability differences (scheduled and unscheduled closures). As the demands of the analysis increased, there was a need to consolidate and dynamically link the various models and techniques developed over the years and to develop new techniques to simultaneously manage investment permutations and automatically select optimal investment plans; the desire was to perform system optimization in a system-level evaluation. The innovative analysis techniques and relational database management structure of the new Ohio River Navigation Investment Model are introduced, as is a set of flexible, integrated analysis modules that move the Corps closer to these ideals.

Transportation operations model analysis for removal of stranded fuel from shutdown reactors

Abstract The transportation operations model was used to identify options for removing stranded fuel currently in dry storage at nine shutdown reactor sites to a hypothetical consolidated storage facility. The logistical variables included the campaign duration, fuel selection priority, consist size and location of the consolidated storage and maintenance facilities. The major factors affecting the logistics of fuel removal were identified. Recommendations for optimal strategies for the transport of stranded fuel from shutdown sites are made.

Used Fuel Management System Architecture and Interface Analyses

Preliminary system-level analyses of the interfaces between at-reactor used fuel management, consolidated storage facilities, and disposal facilities, along with the development of supporting logistics simulation tools, have been initiated to provide the U.S. Department of Energy (DOE) and other stakeholders with information regarding the various alternatives for managing used nuclear fuel (UNF) generated by the current fleet of light water reactors operating in the United States. An important UNF management system interface consideration is the need for ultimate disposal of UNF assemblies contained in waste packages that are sized to be compatible with different geologic media. Thermal analyses indicate that waste package sizes for the geologic media under consideration by the Used Fuel Disposition Campaign may be significantly smaller than the canisters being used for on-site dry storage by the nuclear utilities. Therefore, at some point along the UNF disposition pathway, there could be a need to repackage fuel assemblies already loaded and being loaded into the dry storage canisters currently in use. The implications of where and when the packaging or repackaging of commercial UNF will occur are key questions being addressed in this evaluation. The analysis demonstrated that thermal considerations will have a major impact on the operation of the system and that acceptance priority, rates, and facility start dates have significant system implications.Copyright