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[en] Owing to the diverse nuclear fuel cycle options available, including direct disposal, it is necessary to select the optimum nuclear fuel cycles in consideration of the political and social environments as well as the technical stability and economic efficiency of each country. Economic efficiency is therefore one of the significant evaluation standards. In particular, because nuclear fuel cycle cost may vary in each country, and the estimated cost usually prevails over the real cost, when evaluating the economic efficiency, any existing uncertainty needs to be removed when possible to produce reliable cost information. Many countries still do not have reprocessing facilities, and no globally commercialized HLW (High-level waste) repository is available. A nuclear fuel cycle cost estimation model is therefore inevitably subject to uncertainty. This paper analyzes the uncertainty arising out of a nuclear fuel cycle cost evaluation from the viewpoint of a cost estimation model. Compared to the same discount rate model, the nuclear fuel cycle cost of a different discount rate model is reduced because the generation quantity as denominator in Equation has been discounted. Namely, if the discount rate reduces in the back-end process of the nuclear fuel cycle, the nuclear fuel cycle cost is also reduced. Further, it was found that the cost of the same discount rate model is overestimated compared with the different discount rate model as a whole
[en] The development of a systematic approach to protection of the environment has required a number of basic steps to be taken, including a discussion of what objectives could reasonably be set, together with an examination of how existing knowledge could best be used in order to achieve them. It has required bold decisions to be made, new modelling to be undertaken, and new data sets to be compiled. Equally challenging, however, has been the need to fold the entire subject area into an expanded system originally developed for the protection of human beings. There are, inevitably, a number of data gaps, and further decisions need to be made. However, the priority now is to examine how this approach to protection of the environment can be used in practice. With an intensifying worldwide debate about the environmental merits of different forms of energy production, it would seem imperative that the various practices involved in the nuclear fuel cycle are able to demonstrate, clearly and independently, their own actual or potential impact on the environment. The International Commission on Radiological Protection now has the basic means for such evaluations to be made, and further developments in this system will reflect the experience of its practical application.
[en] Previous PNNL work has shown the existing nuclear fuel markets to provide a high degree of supply security, including the ability to respond to supply disruptions that occur for technical and non-technical reasons. It is in the context of new reactor designs - that is, reactors likely to be licensed and market ready over the next several decades - that fuel supply security is most relevant. Whereas the fuel design and fabrication technology for existing reactors are well known, the construction of a new set of reactors could stress the ability of the existing market to provide adequate supply redundancy. This study shows this is unlikely to occur for at least thirty years, as most reactors likely to be built in the next three decades will be evolutions of current designs, with similar fuel designs to existing reactors.
[en] One of the major research and development (R and D) areas under the Fuel Cycle Research and Development (FCRD) program is advanced fuels development. The Advanced Fuels Campaign (AFC) has the responsibility to develop advanced fuel technologies for the Department of Energy (DOE) using a science-based approach focusing on developing a microstructural understanding of nuclear fuels and materials. Accomplishments made during fiscal year (FY 20) 2011 are highlighted in this report, which focuses on completed work and results. The process details leading up to the results are not included; however, the technical contact is provided for each section. The order of the accomplishments in this report is consistent with the AFC work breakdown structure (WBS).
[en] This chapter considers methods and techniques for computational modeling for nuclear materials with a focus on fuels. The basic concepts for chemical thermodynamics are described and various current models for complex crystalline and liquid phases are illustrated. Also included are descriptions of available databases for use in chemical thermodynamic studies and commercial codes for performing complex equilibrium calculations.
[en] Atomistic modeling using the BFS method for alloys and ab initio based parameters is proposed for the study of fundamental properties of U-Zr metallic nuclear fuels. Due to its basic atomistic nature and the universal character of the parametrization, the approach can be used for diverse problems such as the interaction between fuel and cladding and temperature gradient fuel constituent redistribution. In the first case, preliminary results for the formation of an interaction layer using large scale simulations are presented. For the second case, a mean field formalism is introduced in order to determine concentration profiles for arbitrary changes in temperature in the radial direction. (author)
[en] To provide a brief overview of key arms control and nonproliferation arrangements for the layperson that may be relevant to the Commission's comprehensive review of policies for managing the back end of the nuclear fuel cycle. Primer would be published by the Commission and made publicly available, probably as an appendix to a larger Commission report.
[en] The paper describes the structure of neutron data libraries and upgraded algorithms. The results of test calculations using the new libraries and fuel burnup schemes are also given
[ru]В статье приведено описание структуры нейтронных библиотек и модернизированных алгоритмов. Приводятся результаты тестовых расчетов с использованием новых библиотек и схемы выгорания
[en] Nuclear research within the 7th Framework Program (FP7 and FP7+2) of EURATOM has devoted a significant fraction of its efforts to the development of advanced nuclear fuel cycles and reactor concepts, mainly fast reactors, aiming to improve the long term sustainability by reduction of the final wastes, optimal use of natural resources and improvement of safety in the present and future nuclear installations. The new design need more accurate basic nuclear data for isotopes, like minor actinides, potentially playing an important role in the operation, fuel concept, safety or final wastes of those reactors and fuel cycles. Four projects, ANDES, ERINDA, EUFRAT and CHANDA, supported by EURATOM within the FP7 and FP7+2, have put together most of the European Nuclear Data community to respond efficiently and in a coordinated way to those needs. This paper summarizes the objectives, and main achievements of ANDES, the project responsible for most of the measurements and technical achievements that was coordinated by CIEMAT. Indeed, CIEMAT has coordinated the nuclear data R and D projects within EURATOM during the last 7 years (NUDATRA domain of EUROTRANS, and ANDES) and will continue this coordination in the CHANDA project till 2017. (Author)
[en] In the International Atomic Energy Agency, acquisition path analysis (APA) is indispensable to safeguards implementation. It is an integral part of both State evaluation process and the development of State level safeguards approaches, all performed through ongoing collaborative analysis of all available safeguards relevant information by State evaluation groups (SEG) with participation of other contributors, as required. To perform comprehensive State evaluation, to develop and revise State-level safeguards approaches, and to prepare annual implementation plans, the SEG in its collaborative analysis follows accepted safeguards methodology and guidance. In particular, the guide ''Performing Acquisition Path Analysis for the Development of a State-level Safeguards Approach for a State with a CSA'' is used. This guide identifies four major steps of the APA process: 1. Consolidating information about the State's past, present and planned nuclear fuel cycle-related capabilities and infrastructure; 2. Identifying and visually presenting technically plausible acquisition paths for the State; 3. Assessing acquisition path steps (State's technical capabilities and possible actions) along the identified acquisition paths; and 4. Assessing the time needed to accomplish each identified technically plausible acquisition path for the State. The paper reports on SEG members' and other contributors' experience with APA when following the above steps, including the identification of plausible acquisition pathways, estimation of time frames for all identified steps and determination of the time needed to accomplish each acquisition path. The difficulties that the SEG encountered during the process of performing the APA are also addressed. Feedback in the form of practical suggestions for improving the clarity of the acquisition path step assessment forms and a proposal for software support are also included. (author)