The limitation of 235U enrichment is a current concern among IAEA Member States. In response, work has been undertaken to provide a platform to facilitate a comprehensive review of the current status, prospects and challenges associated with the use of fuels having enrichments higher than 5 % 235U in light water reactors. This publication is the outcome of two technical meetings and compiles the results and conclusions in terms of benefits to be obtained from the use of high assay low enriched uranium (HALEU) fuel, with due consideration of safety issues that arise from its use. It details technological options and corresponding issues regarding fuel and core design, safety analysis and assessments relevant to manufacturing, handling, transportation, storage, irradiation, and performance in normal and accident conditions.

Originally published in 1983, this book presents both the technical and political information necessary to evaluate the emerging threat to world security posed by recent advances in uranium enrichment technology. Uranium enrichment has played a relatively quiet but important role in the history of efforts by a number of nations to acquire nuclear weapons and by a number of others to prevent the proliferation of nuclear weapons. For many years the uranium enrichment industry was dominated by a single method, gaseous diffusion, which was technically complex, extremely capital-intensive, and highly inefficient in its use of energy. As long as this remained true, only the richest and most technically advanced nations could afford to pursue the enrichment route to weapon acquisition. But during the 1970s this situation changed dramatically. Several new and far more accessible enrichment techniques were developed, stimulated largely by the anticipation of a rapidly growing demand for enrichment services by the world-wide nuclear power industry. This proliferation of new techniques, coupled with the subsequent contraction of the commercial market for enriched uranium, has created a situation in which uranium enrichment technology might well become the most important contributor to further nuclear weapon proliferation. Some of the issues addressed in this book are: A technical analysis of the most important enrichment techniques in a form that is relevant to analysis of proliferation risks; A detailed projection of the world demand for uranium enrichment services; A summary and critique of present institutional non-proliferation arrangements in the world enrichment industry, and An identification of the states most likely to pursue the enrichment route to acquisition of nuclear weapons.

This publication summarizes the findings and conclusions of an IAEA coordinated research project (CRP) on fuel modelling in accident conditions, which was initiated under the IAEA Action Plan on Nuclear Safety following the Fukushima accident. The overall aim of the project was to analyse and better understand fuel behavior in accident conditions, with a focus on loss of coolant accidents. In the course of the project the participants used a mixture of data derived from accident simulation experiments, in particular data designed to investigate the fuel behaviour during design basis accident and design extension conditions. They carried out calculations on priority cases selected from a matrix of cases identified at the first research coordination meeting and designed to support their individual priorities. These priority cases were chosen as the best available to help determine which of the many models used in the codes best reflect reality. The CRP provided an ideal platform to compare their code results with others and especially with experimental data, to which they otherwise would not have had access. The achievements made within this CRP fostered new collaborations and enhanced the development and improvement of common models and highlighted differences in the interpretation of some experiments and therefore in the use of the codes ? the so-called user effects.

The so-called nuclear renaissance has increased worldwide interest in nuclear power. This potential growth also has increased, in some quarters, concern that nonproliferation considerations are not being given sufficient attention. In particular, since introduction of many new power reactors will lead to requiring increased uranium enrichment services to provide the reactor fuel, the proliferation risk of adding enrichment facilities in countries that do not have them now led to proposals to provide the needed fuel without requiring indigenous enrichment facilities. Similar concerns exist for reprocessing facilities. Internationalization of the Nuclear Fuel Cycle summarizes key issues and analyses of the topic, offers some criteria for evaluating options, and makes findings and recommendations to help the United States, the Russian Federation, and the international community reduce proliferation and other risks, as nuclear power is used more widely. This book is intended for all those who are concerned about the need for assuring fuel for new reactors and at the same time limiting the spread of nuclear weapons. This audience includes the United States and Russia, other nations that currently supply nuclear material and technology, many other countries contemplating starting or growing nuclear power programs, and the international organizations that support the safe, secure functioning of the international nuclear fuel cycle, most prominently the International Atomic Energy Agency.

This publication presents the material properties of all unirradiated Uranium-Molybdenum (U-Mo) fuel constituents that are essential for fuel designers and reactor operators to evaluate the fuel's performance and safety for research reactors. Many significant advances in the understanding and development of low enriched uranium U-Mo fuels have been made since 2004, stimulated by the need to understand irradiation behavior and early fuel failures during testing. The publication presents a comprehensive overview of mechanical and physical property data from U-Mo fuel research

This publication reports on the results of a coordinated research project on advances in high temperature gas cooled reactor (HTGR) fuel technology and describes the findings of research activities on coated particle developments. These comprise two specific benchmark exercises with the application of HTGR fuel performance and fission product release codes, which helped compare the quality and validity of the computer models against experimental data. The project participants also examined techniques for fuel characterization and advanced quality assessment/quality control. The key exercise included a round-robin experimental study on the measurements of fuel kernel and particle coating properties of recent Korean, South African and US coated particle productions applying the respective qualification measures of each participating Member State. The summary report documents the results and conclusions achieved by the project and underlines the added value to contemporary knowledge on HTGR fuel.