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The optimisation of the nuclear fuel cycle is a key issue for the sustainability of nuclear energy. This book presents the papers from a workshop which investigated alternative nuclear energy futures, with emphasis on back-end of the fuel cycle options that could enhance the sustainability of nuclear energy in the long term, to 2050 and beyond. The papers lay out the conditions that need to be fulfilled for nuclear energy to remain a viable option and highlight the technological and strategic developments underway to address those issues. Subjects covered include natural resource management, radioactive waste minimisation, cost reduction and proliferation resistance aspects of alternative reactor and fuel cycle technologies.
In response to growing interest in high-temperature, gas-cooled reactors (HTGRs) in many countries and the need for improved materials for nuclear applications in high-temperature environments, the NEA organised the Third Information Exchange Meeting on Basic Studies in the Field of High-temperature Engineering. The proceedings of this meeting provide an overview of high-temperature research currently under way, including studies on the behaviour of irradiated graphite and improvements in material properties under high-temperature irradiation. These proceedings also contain recommendations for further international work in the areas of high-temperature engineering.
In response to increasing interest in high-temperature, gas-cooled reactors (HTGRs) in many countries and the need for improved materials for nuclear applications in high-temperature environments, the NEA organised a Second Information Exchange Meeting on Basic Studies in the Field of High-temperature Engineering. These proceedings provide an overview of the activities being carried out in eight countries, the improvement of material properties for HTGR application, in-core monitoring methods and properties of irradiated graphite, and HTGR fuel fabrication and performance.
Understanding the accident at the Fukushima Daiichi Nuclear Power Plant is important for safe and timely decommissioning of the reactors. This objective, together with the development of better computer codes for analysis of severe accidents, was the aim of the benchmark study conducted under the auspices of the OECD Nuclear Energy Agency. Through the diversity of the modelling codes and approaches, and the use of parametric studies, it has been possible to identify the more likely scenarios that can fit with the limited data available from the accident. The insights gained from the project will help guide research into severe accident behaviour, improve severe accident computer codes, develop accident mitigation and response at nuclear power plants, support regulatory oversight related to severe accidents, and inform policies on the development and deployment of nuclear technology.
Many of the failures that occur in nuclear fuel rods in light water reactors around the world are caused by the phenomenon of mechanical interaction between pellets and cladding (PCMI). The process is extremely complex to simulate, therefore the models involved must be continuously improved and subjected to validation with experiments and comparison to other similar codes.
This benchmark study of PCMI is aimed to improve the understanding and modelling of PCMI. The study engaged investigators representing the main fuel performance simulation groups in the world. After a detailed analysis of the results of all the participants, a series of conclusions have been drawn. The results are captured in two volumes: Volume 1: Hypothetical Beginning-of-Life Power Ramps (NEA, 2024) and Volume 2: Validation of Beginning-of-Life Power Ramping (this publication).
Many of the failures that occur in nuclear fuel rods in light water reactors around the world are caused by the phenomenon of mechanical interaction between pellets and cladding (PCMI). The process is extremely complex to simulate, therefore the models involved must be continuously improved and subjected to validation with experiments and comparison to other similar codes.
This benchmark study of PCMI aims to improve the understanding and modelling of PCMI. The study engaged investigators representing the main fuel performance simulation groups in the world. After a detailed analysis of the results of all the participants, a series of conclusions have been drawn. The results are captured in two volumes: Volume 1: Hypothetical Beginning-of-Life Power Ramps (this publication) and Volume 2: Validation of Beginning-of-Life Power Ramping (NEA, 2024).
The radiation dose rate emitted by spent fuel assemblies is a crucial parameter within the framework of proliferation resistance, and its accurate determination is hence of paramount importance. Recent calculations have shown some discrepancies with historical results for pressurised water reactor spent fuel assemblies. To verify these discrepancies and help define a reference calculation, an international benchmark was carried out under the framework of the Nuclear Energy Agency (NEA) Expert Group on Advanced Fuel Cycle Scenarios (EGAFCS). The benchmark aimed to verify updated dose rate calculation procedures (new modelling approaches, new nuclear data, new versions of calculation codes) and share the benchmark results at the international level. The benchmark, including code-to-code verification and validation against experimental data, has shown and validated a methodology for the adequate estimation of the radiation dose rate from pressurised water reactor spent fuel assemblies (UOX and MOX) after certain periods of decay, confirming also the self-resistance of the simulated assemblies. This report outlines the exercise, its results and a series of recommendations for calculations.
This publication presents a comprehensive and up-to-date survey of isotope production capabilities and uses in the world and an analysis of issues related to isotope production and use including transportation, sealed source accountability, maintaining the government role, and third party liability concerns.
Isotopes, radioactive and stable, are used worldwide in various applications related to medical diagnosis or care, industry and scientific research. More than fifty countries have isotope production or separation facilities operated for domestic supply, and sometimes for international markets.
This publication provides up-to-date information on the current status of, and trends in, isotope uses and production. It also presents key issues, conclusions and recommendations, which will be of interest to policy makers in governmental bodies, scientists and industrial actors in the field.
Radioactive and stable isotopes are used throughout the world and in many sectors, including medicine, industry, agriculture and research. In many applications isotopes have no substitute, and in most others they are more effective and cheaper than alternative techniques or processes.
This publication is the first international survey on the beneficial uses and production of isotopes. It provides an overview of their main uses, and detailed information on the facilities that produce them world-wide. Trends in isotope supply and demand are analysed, and the conclusions and recommendations presented point to key issues to be considered by governments.
The societal aspects of risk governance are increasingly becoming a part of public decision-making processes. This tendency is particularly evident in matters dealing with the protection of human health and the environment. The NEA Committee on Radiation Protection and Public Health organised a workshop to examine stakeholder involvement processes through which governments and regulators can arrive at accepted decisions regarding radiological protection. An example of an area in which stakeholder involvement is important is the clean-up of sites contaminated by accidents or by past industrial or research activities.
These proceedings address the roles of various stakeholders in the decision-making process, and their expectations regarding how a modern system of radiological protection should be integrated within the broader context of risk governance. Case studies are presented to illustrate good practice and as a basis for drawing conclusions regarding general lessons that can be applicable in many different national contexts. These proceedings will be of interest to policy makers, radiation protection experts and interested members of the public.
Nuclear energy is an important source of low-carbon electricity and thus plays a significant role in avoiding carbon emissions. It has the potential to decarbonise the global energy sector even further by also providing heat for industrial applications and residential heating, which both continue to run mainly on fossil fuels. More than 65 nuclear reactors around the world (about 15% of the total) with decades of experience demonstrate on a daily basis the feasibility of providing non-electric applications of nuclear energy such as district heating, desalination or other forms of process heat.
In order to further reduce carbon emissions, the share of nuclear reactors used for cogeneration needs to be expanded. However, until recently the economic competitiveness of thermal energy produced by nuclear power plants has been a challenge. Not accounting for climate change impacts, heat produced by gas- or coal-fired power plants has frequently been cheaper. Yet, as fossil fuel prices rise and carbon costs are increasingly accounted for, the economics of nuclear cogeneration begin to look more favourable. A good understanding of the technical realities and economics of nuclear cogeneration, including its implications for electricity and energy systems, is essential to take advantage of this changed environment. This NEA report provides a thorough overview of nuclear cogeneration, with a view to helping energy decisionmakers and interested experts in assessing the costs and benefits of having nuclear energy provide both low-carbon electricity and low-carbon heat.
Ten years after the Fukushima Daiichi Nuclear Power Plant accident, many lessons have been learnt that have helped improve preparedness for nuclear emergencies and awareness of the global risks that such accidents can entail. This includes a number of long-lasting, multidimensional impacts on health(including mental health and psychosocial support), the economy, and the environment. Recovery from a nuclear or radiological accident is a long, complex and resource-intensive process. To facilitate efficient recovery, it is important to establish processes and procedures during the preparedness phase to activate the resources required and to involve the relevant stakeholders at all levels. This report addresses the need for a harmonised approach towards efficient recovery management from nuclear or radiological accidents, which aims to assist countries to develop their own national plans and procedures for post-accident recovery preparedness in a harmonised manner, through the introduction of a cyclical approach.
An important factor for public confidence in the nuclear regulator is the general public trust of the government and its representatives, which is clearly not the same in all countries. These workshop proceedings identify a number of common principles for the communication of nuclear regulatory decisions that can be recommended to all regulators. They have been cited in particular for their ability to help build, measure and/or improve overall public confidence in the nuclear regulator.
The OECD/NEA Expert Group on Burn-up Credit was established in 1991 to address scientific and technical issues connected with the use of burn-up credit in nuclear fuel cycle operations. Following the completion of six benchmark exercises with uranium oxide fuels irradiated in pressurised water reactors (PWRs) and boiling water reactors (BWRs), the present report concerns mixed uranium and plutonium oxide (MOX) fuels irradiated in PWRs.
The report summarises and analyses the solutions to the specified exercises provided by 37 contributors from 10 countries. The exercises were based upon the calculation of infinite PWR fuel pin cell reactivity for fresh and irradiated MOX fuels with various MOX compositions, burn-ups and cooling times. In addition, several representations of the MOX fuel assembly were tested in order to check various levels of approximations commonly used in reactor physics calculations.
The OECD/NEA Expert Group on Burn-up Credit was established in 1991 to address scientific and technical issues connected with the use of burn-up credit in nuclear fuel cycle operations. Following the completion of six benchmark exercises with uranium oxide (UOX) fuels irradiated in pressurised water reactors (PWRs) and boiling water reactors (BWRs), the present report concerns mixed uranium and plutonium oxide (MOX) fuels irradiated in PWRs.
The exercises consisted of inventory calculations of MOX fuels for two initial plutonium compositions. The depletion calculations were carried out using three representations of the MOX assemblies and their interface with UOX assemblies. This enabled the investigation of the spatial and spectral effects during the irradiation of the MOX fuels.
Energy and nuclear policy makers face many challenges as they evaluate options to ensure an adequate supply of electricity while pursuing environmental, economic and energy security goals. Many analysts suggest that nuclear’s share of global energy supply could decrease in coming decades. If energy markets and national energy policies continue along "business as usual" lines, what are the issues that arise? What are the consequences for the long-term availability of nuclear technology and expertise? This book identifies the issues in a series of papers presented at a recent meeting jointly organised by the International Energy Agency and the OECD Nuclear Energy Agency. Senior energy policy makers and industry executives from OECD Member countries contributed these analyses. They offer a realistic assessment of nuclear’s potential contribution, and the major challenges awaiting nuclear energy and energy supply in general. For those seeking a review of the current issues facing nuclear power within the broad context of energy policy, this is an essential report.