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The computer code system PENELOPE (version 2011) performs Monte Carlo simulation of coupled electron-photon transport in arbitrary materials for a wide energy range, from a few hundred eV to about 1 GeV. Photon transport is simulated by means of the standard, detailed simulation scheme. Electron and positron histories are generated on the basis of a mixed procedure, which combines detailed simulation of hard events with condensed simulation of soft interactions. A geometry package called PENGEOM permits the generation of random electron-photon showers in material systems consisting of homogeneous bodies limited by quadric surfaces, i.e. planes, spheres, cylinders, etc. This report is intended not only to serve as a manual of the PENELOPE code system, but also to provide the user with the necessary information to understand the details of the Monte Carlo algorithm.
The computer code system PENELOPE (version 2014) performs Monte Carlo simulation of coupled electron-photon transport in arbitrary materials for a wide energy range, from a few hundred eV to about 1 GeV. Photon transport is simulated by means of the standard, detailed simulation scheme. Electron and positron histories are generated on the basis of a mixed procedure, which combines detailed simulation of hard events with condensed simulation of soft interactions. A geometry package called PENGEOM permits the generation of random electron-photon showers in material systems consisting of homogeneous bodies limited by quadric surfaces, i.e., planes, spheres, cylinders, etc. This report is intended not only to serve as a manual of the PENELOPE code system, but also to provide the user with the necessary information to understand the details of the Monte Carlo algorithm.
The computer code system PENELOPE (version 2018) performs Monte Carlo simulation of coupled electron-photon transport in arbitrary materials for a wide energy range, from a few hundred eV to about 1 GeV. Photon transport is simulated by means of the standard, detailed simulation scheme. Electron and positron histories are generated on the basis of a mixed procedure, which combines detailed simulation of hard events with condensed simulation of soft interactions. A geometry package called PENGEOM permits the generation of random electron-photon showers in material systems consisting of homogeneous bodies limited by quadric surfaces, i.e., planes, spheres, cylinders, cones, etc. This report is intended not only to serve as a manual of the PENELOPE code system, but also to provide the user with the necessary information to understand the details of the Monte Carlo algorithm.
National radioactive waste management programmes are in various phases of siting facilities and rely on distinct technical approaches for different categories of waste. In all cases, it is necessary for institutional actors and the potential or actual host community to build a meaningful, workable relationship. Partnership approaches are effective in achieving a balance between the requirements of fair representation and competent participation. With host community support, they also help ensure the desirable combination of a licensable site and management concept as well as a balance between compensation, local control and development opportunities. This report provides up-to-date information on experience with local partnership arrangements in 13 countries. The characteristics, advantages and aims of community partnerships are also described in addition to the concept's evolution over the past decade.
This report communicates the results of an international seminar which reviewed recent progress in the field of pellet-clad interaction in light water reactor fuels. It also draws a comprehensive picture of current understanding of relevant phenomena and their impact on the nuclear fuel rod, under the widest possible conditions. State-of-the-art knowledge is presented for both uranium-oxide and mixed-oxide fuels.
With a declining number of nuclear data evaluators in the world and an increasing demand for high-quality data, there is a risk that evaluators will concentrate on producing new nuclear data to the detriment of developing new models and methods for evaluating existing data. In this context, it is essential to identify the basic physics issues that are going to be important for future nuclear data evaluation processes. At the same time, demand for new types of data, which will be needed in emerging nuclear applications, could warrant new evaluation techniques that are presently only used in the context of fundamental research and not in nuclear data production. These proceedings present the main findings of the "Perspectives on Nuclear Data for the Next Decade" workshop, which explored innovative approaches to nuclear data evaluation with the aim of opening new perspectives, building new research programmes and investigating prospects for international collaboration.
Following the 2011 accident at the Fukushima Daiichi nuclear power plant, several high-priority actions were initiated by the NEA to address certain technical issues at nuclear power plants. One of these actions was to prepare a status report on spent fuel pools (SFPs) under loss-of-cooling and loss-of-coolant accident conditions, which was issued in 2015, providing an overview of both SFP accidents and mitigation strategies.
The present report is a follow up to this status report, documenting the results of a Phenomena Identification and Ranking Table (PIRT) exercise conducted by the NEA. This PIRT exercise identified SFP accident phenomena that are of high importance and yet are highly uncertain, thus highlighting their primary interest for further studies. The report recommends further support for existing experimental programmes and the establishment of a number of new programmes to focus, for example, on large-scale thermal-hydraulic experiments on the coolability of partly or completely uncovered spent-fuel assemblies and the investigation of spray cooling for uncovered spent-fuel assemblies in typical storage racks.
Following recent disarmament agreements, the Russian Federation and the USA have declared part of their stockpiles of weapons-grade plutonium as a surplus to their national defense needs. This material needs to be disposed of, and one of the suggested means of doing so is burning it in existing reactors and transforming the material into spent fuel. The experience in these two countries with mixed oxide fuel (MOX) is either dated or scarce. Several European countries and Japan, however, have acquired much experience in using MOX fuel in reactors which was shared at this important workshop.
This publication presents the workshop results which reviewed existing technical information from the civil nuclear power programmes that are beneficial to weapons-grade plutonium disposition. It also proposes concrete actions that could help expedite this process in the near future.
The OECD/NEA Working Party on the Physics of Plutonium Fuels and Innovative Fuel Cycles (WPPR) conducted a physics code benchmark test for the recycling of plutonium as PuO2/UO2 mixed-oxide (MOX) fuel in boiling water reactors (BWRs) compared to pressurised water reactors (PWRs). This volume reports on the benchmark results and conclusions that can be drawn from it.
Although the recycling of plutonium as thermal mixed-oxide (MOX) fuel in pressurised water reactors (PWRs) is now well-established on a commercial scale, many physics questions remain. The main question addressed in this report is the number of times plutonium can effectively be recycled in a PWR.
This report describes in particular an exercise based on a realistic, multiple-recycle scenario, which followed plutonium through five generations of recycling in a PWR. It considered both a standard PWR design currently in use and a highly moderated design. The latter is a possible option for a dedicated, MOX-fuelled PWR in which it would be possible to optimise the moderation for plutonium. The study of these two designs in parallel has provided a better understanding of their relative merits, as well as insight into the limitations of multiple recycling and the long-term toxicity of fission products and actinides.
The definition of the chemical and isotopic composition of the groundwater present in argillaceous formations, which are considered as potential host rocks for radioactive waste disposal, is crucial for establishing their barrier properties. Therefore, a critical review of the relevant literature on the current methods applied to extract water and solutes and on the various approaches to the interpretation of their results was commissioned to the Laboratoire d’hydrologie et de géochimie isotopique (Université de Paris-Sud, France). The present document provides a synthesis of available extraction methods, assesses their respective advantages and limitations, identifies key processes that may influence the composition of the extracted water, describes modelling approaches that are used to determine in situ porewater composition, and highlights, wherever possible, some of the unresolved issues and recommendations on ways to address them.
This report compiles and shares some of the lessons learnt from implementing post-Fukushima actions related to human and organisational factors (HOF), including at nuclear facility operating companies, technical support organisations, research institutions, and regulatory authorities. It summarises a two-phase information-gathering exercise, overseen by the NEA Working Group on Human and Organisational Factors, about the requirements and guidelines that countries and nuclear licensees have adopted since the accident. The report discusses the central role of human and organisational performance in mitigating extreme external events and the management of severe accidents. It addresses the importance of validating the ability to perform these actions, and the challenges associated with performing such validations with fidelity to the conditions likely to be present during such events. The report concludes by providing four key recommendations that seek to promote greater sharing of information and the identification of best practices.
The transition from an operating nuclear facility to the decommissioning phase is critical in the life cycle of every facility. A number of organisational and technical modifications are needed in order for the facility to meet new objectives and requirements, and a certain number of activities must be initiated to support the transition and preparation for the dismantling of the facility. Thorough preparation and planning is key for the success of global decommissioning and dismantling projects, both to minimise delays and undue costs and to ensure a safe and efficient decommissioning process.
The aim of this report is to inform regulatory bodies, policy makers and planners about the relevant aspects and activities that should begin during the last years of operation and following the end of operation. Compiling lessons learnt from experiences and good practices in NEA member countries, the report supports the further optimisation of transition strategies, activities and measures that will ensure adequate preparation for decommissioning and dismantling.
Radioactive waste repositories are designed to isolate waste from the living environment without human intervention over extended periods of time. Nevertheless, the intention is not to abandon the repositories, but to provide the oversight that is necessary to ensure that they are not forgotten by society. In response to this challenge, the Nuclear Energy Agency launched the international initiative “Preservation of Records, Knowledge and Memory (RK&M) Across Generations”. As a result, an in-depth understanding of this issue was developed, as well as a specific methodology to address it. The RK&M preservation toolbox, for example, offers a menu with 35 different preservation mechanisms and guidelines on how to combine and implement them.
This report may be used as a general guide to the RK&M preservation topic. It presents a historical review, addresses ethical considerations, analyses the fundamentals of RK&M preservation, outlines various mechanisms and indicates how to develop these mechanisms into a systemic RK&M preservation strategy. The report aims to inspire and assist a variety of actors so that they can discuss and develop national and repository-specific RK&M preservation strategies.
Radioactive waste repositories are designed to be intrinsically safe in that they are not dependent on the presence or intervention of humans. In response to this challenge, the Nuclear Energy Agency initiated the Preservation of Records, Knowledge and Memory (RK&M) Across Generations Initiative, calling on the international community to help create specific means to preserve RK&M.
The concept of a key information file (KIF) emerged in response to the challenge presented by the large volumes of RK&M material generated by national disposal programmes. This concept has been developed into an important component of a RK&M preservation strategy. The KIF is designed to be a single, short document, produced in a standard format, with the aim of allowing society to understand the nature and intent of a repository, and thus to reduce the likelihood of unnecessary human intrusion. It should be made openly available and ultimately be widely distributed.
This report describes the KIF concept in detail, in a manner that should enable those concerned with any particular repository to create their own versions. Three draft key information files, currently under development to support RK&M preservation in France, Sweden and the United States, are provided as examples.
Principles and Practice of International Nuclear Law examines the various interrelated legal issues for the safe, efficient and secure use of nuclear energy. It provides an overview of the complex body of laws and legal regimes in international nuclear law, as well as the many developments that have unfolded in recent years impacting all aspects of nuclear safety, security, safeguards and liability. It also gives a concise overview of the main international institutions, and addresses such issues as radiological protection, nuclear safety, environmental protection, nuclear transport, nuclear security, safeguards, nuclear third party liability and compensation for nuclear damage, insurance, nuclear trade and project development.
The Fifth International Nuclear Emergency Exercise (INEX-5) was developed in response to NEA member countries' desire to test and demonstrate the value of changes put in place following the Fukushima Daiichi nuclear power plant accident. INEX-5 was held during 2015 and 2016, and was followed by the Fifth International Nuclear Emergency Exercise (INEX-5) Workshop in early 2017. Representatives from 22 member countries, the International Atomic Energy Agency and the European Commission attended the workshop, where participants identified elements emerging from INEX-5 that would help improve international and national arrangements for notification, communication and interfaces related to catastrophic events involving radiation or radiological materials.
The workshop was an interactive experience structured around invited presentations, moderated discussions and breakout groups that addressed the four broad topics of communication and information sharing with other countries and international partners; cross-border and international co-ordination of protective actions; mid- and long-term aspects of recovery; and connections with the work of other international organisations and networks. These proceedings provide a summary of the proposals and recommendations for future work in emergency management.
This is the fifth study in a series on the future costs of generating electricity. It reviews cost estimates for power plants using nuclear, coal, gas and renewable energy sources. Experts from fourteen OECD countries and five non-OECD countries provided estimated costs for investment, for operations and maintenance, and for fuel for more than 70 power plants. A uniform, consistent method of analysis produces comparable, levelised costs of electricity (cents/kWh). The study also analyses the effects on generation costs of variations in economic lifetime, plant load, and fossil fuel price escalation. An authoritative reference in the field, this publication will be especially useful to electricity system analysts and experts in electric power economics.
This sixth study in a series on projected costs of generating electricity presents and analyses cost estimates for some 130 power and co-generation (heat and power) plants using coal, gas, nuclear and renewable energy sources. Experts from 19 OECD member countries, 2 international organisations and 3 non-member countries contributed to the study.
The levelised lifetime costs presented and analysed were calculated with input data from participating experts and commonly agreed generic assumptions, using a uniform methodology. Key issues related to generation costs are addressed in the report, including methodologies to incorporate risk in cost assessments, impact of carbon emission trading and integration of wind power into electricity grids.
A reference in the field, this publication will be of interest to energy policy makers, electricity system analysts and energy economists.
This joint IEA/NEA report on electricity generating costs presents the latest data available for a wide variety of fuels and technologies, including coal and gas (with and without carbon capture), nuclear, hydro, onshore and offshore wind, biomass, solar, wave and tidal as well as combined heat and power (CHP). It provides levelised costs of electricity (LCOE) per MWh for almost 200 plants, based on data covering 21 countries (including four major non-OECD countries), and several industrial companies and organisations. For the first time, the report contains an extensive sensitivity analysis of the impact of variations in key parameters such as discount rates, fuel prices and carbon costs on LCOE. Additional issues affecting power generation choices are also examined.