REDUNDANCY IN THE INTERNATIONAL NUCLEAR FUEL MARKET: TECHNICALLY REDUNDANT AND POLITICALLY ASSURED FUEL SUPPLY

摘要

A number of assured fuel supply proposals are under international consideration for the provision of front end nuclear fuel cycle services. Three "fuel bank" proposals are moving toward implementation - (the IAEA/NTI fuel bank, the Russian bank at Angarsk, and the American Fuel Supply (AFS) reserve, all of which provide for reserves of low enriched uranium (LEU). In order to be effective, a system of fuel assurance mechanisms must account for the delivery of fabricated fuel assemblies. Fabrication is in fact the step in the supply chain that will determine the extent of substitution among fuel vendors possible in the event of an interruption of supply, whether for technical or political reasons. Pacific Northwest National Laboratory (PNNL) has been assessing the reliability of fuel supply from the perspective of technical and non-technical (i.e. country level) redundancy among fuel vendors. This work has entailed modeling outages of varying durations at particular fabrication plants, thus characterizing the ability of the market to accommodate unforeseeable disruptions in the fabrication sector itself. This work has been done using discrete-event simulation to model the re-assignment of fuel reload production to alternative fabrication plants based on defined outage scenarios. The results enable visualization of the effects of outages - specifically the feasibility of shifting assembly production to alternate plants, constrained by various sets.of assumptions on their capabilities to produce specific fuel designs for specific reactors. Developing a clearer picture of the plants, reactors and countries vulnerable to supply disruption enables us both [1] to predict confidently that industry mechanisms could be expected to adapt to physical or political circumstances and provide fabricated fuel on an assured basis, or [2] to identify measures (either by industry alone or with possible involvement by governmental/multilateral agencies) that would add to fuel supply chain reliability.