NUCLEAR ENERGY AGENCY AN A S S E S S M E NT NUCLEAR ENERGY AGENCY PLUTONIUM R IB AN A S S E S S M E NT REPORT BY AN EXPERT GROUP ORGANISATION FOR ECONOMIC CO-OPERATION AND DEVELOPMENT Pursuant to article 1 of the Convention signed in Paris on 14th December 1960, and which came into force on 30th September 1961, the Organisation for Economic Co-operation and Development (OECD) shall promote policies designed: - to achieve the highest sustainable economic growth and employment and a rising standard of living in Member countries, while maintaining financial stability, and thus to contribute to the development of the world economy; - to contribute to sound economic expansion in Member as well as non-member countries in the process of economic development; and - to contribute to the expansion of world trade on a multilateral, non-discriminatory basis in accordance with international obligations. The original Member countries of the OECD are Austria, Belgium, Canada, Denmark, France, the Federal Republic of Germany, Greece, Iceland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, Turkey, the United Kingdom and the United States. The following countries became Members subsequently through accession at the dates indicated hereafter: Japan (28th April 1964), Finland (28th January 1969), Australia (7th June 1971) and New Zealand (29th May 1973). The Socialist Federal Republic of Yugoslavia takes part in some of the work of the OECD (agreement of 28th October 1961). The OECD Nuclear Energy Agency (NEA) was established on 1st February 1958 under the name of the OEEC European Nuclear Energy Agency. It received its present designation on 20th April 1972, when Japan became its first non-European full Member. NEA membership today consists of all European Member countries of OECD as well as Australia, Canada, Japan and the United States. The commission of the European Communities takes part in the work of the Agency. The primary objective of NEA is to promote co-operation among the governments of its participating countries in furthering the development of nuclear power as a safe, environmen tally acceptable and economic energy source. This is achieved by: - encouraging harmonisation of national regulatory policies and practices, with particular -eference to the safety of nuclear installations, protection of man against ionising radiation and preservation of the environment, radioactive waste management, and nuclear third party liability and insurance; - assessing the contribution of nuclear power to the overall energy supply by keeping under review the technical and economic aspects of nuclear power growth and forecasting demand and supply for the different phases of the nuclear fuel cycle; - developing exchanges of scientific and technical information particularly through participation in common services; - setting up international research and development programmes and joint under takings. In these and related tasks, NEA works in close collaboration with the International Atomic Energy Agency in Vienna, with which it has concluded a Co-operation Agreement, as well as with other international organisations in the nuclear field. © OECD, 1989 Application for permission to reproduce or translate all or part of this publication should be made to: Head of Publications Service, OECD 2, rue Andre-Pascal, 75775 PARIS CEDEX 16, France. FOREWORD Several earlier Nuclear Energy Agency studies have looked at aspects of plutonium use. The Working Party on Nuclear Fuel Cycle Requirements, in Nuclear Energy and Its Fuel Cycle: Prospects to 2025 (1) and earlier publications, have considered the regional and global implications for uranium demand of reactor and fuel cycle strategies, some of which have involved the use of plutonium in mixed uranium - plutonium oxide fuels (MOX) in both thermal and fast reactors. They have also estimated the quantities of plutonium that will be produced in spent thermal reactor fuel and the quantities that are likely to be separated from this fuel by reprocessing and stockpiled in OECD and other regions of the world over the next 35 years. Other NEA working parties have looked in detail at the options for Spent Fuel Management (2), including fuel reprocessing and plutonium recovery, and at The Environmental arid Biological Behaviour of Plutonium and Some Other Traiisuranium Elements (3). The Study on The Economics of the Nuclear Fuel Cycle (4) completed in 1985 included some preliminary comments on the economics of plutonium recovery and its use in thermal reactor fuels, focussing on light water reactors (LWRs) but including the Japanese Advanced Thermal Reactor. It was during the course of this last study that the need for a more detailed review was identified, bringing together the latest views on the general characteristics of plutonium and the economics and logistics of its use, in a single easily understood booklet. The need for such a study has been strengthened by the steadily increasing use of mixed oxide fuels in thermal reactors in European OECD countries and Japan. The present study has been undertaken therefore with three primary objectives: (a) to set out simply and clearly the facts about plutonium and its present and future civil use; (b) to explain the factors that influence decisions on the use or non-use of plutonium fuel in thermal reactors; and (c) to illustrate how economic and material flow assessments of alternative fuel choices can be undertaken with stress on the situation over the next ten years. Experts from eleven OECD countries and three international organisations participated in the Working Group; a full list is provided in Annex K. The report has been prepared by the experts and does not necessarily represent the views of member governments or participating organisations, nor should it be taken to imply that all governments have definite views on the matters discussed. ACKNOWLEDGEMENT The Expert Group wishes to thank Belgonucleaire and the Power Reactor and Nuclear Fuel Development Corporation (PNC) of Japan for their assistance with the core physics and economic calculations respectively. 3 TABLE OF CONTENTS EXECUTIVE SUMMARY " INTRODUCTION 14 Part 1. THE OCCURRENCE AND PROPERTIES OF PLUTONIUM AND ITS COMPOUNDS .... 16 1.1 Occurrence of Plutonium '6 1.2 Physical and Chemical Properties of Plutonium and its Compounds '6 1.2.1 Plutonium Metal , '6 1.2.2 Plutonium Compounds '7 1.3 Plutonium Isotopic Composition '7 1.4 Plutonium Radioactivity 24 1.5 The Toxicity of Plutonium 26 1.6 Plutonium Fission 27 1.6.1 The Fission Process 27 1.6.2 Plutonium Fissionability 29 Part 2. UTILISATION AND NON-UTILISATION OPTIONS: THEIR LOGISTICS AND ECONOMICS 32 2.1 Preamble 32 2.2 Utilisation and Non-Utilisation Options 32 2.3 Technical Factors Affecting Decisions on Plutonium Recovery and Use 35 2.3.1 The factors considered 35 2.3.2 Storage Limitations for Spent Thermal Fuel 35 2.3.3 Fuel Burn-Up and Plutonium Quality 35 2.3.4 Timing of Reprocessing and Plutonium Quality 35 2.3.5 Reactor Control 39 2.4 The Logistics of Plutonium Recycle 40 2.4.1 General 40 2.4.2 Plutonium Production in Uranium Fuelled Thermal Reactors 40 2.4.3 Uranium Savings from Uranium Recycle 40 5 2.4.4 Uranium Savings from Plutonium Recycle 42 2.4.5 Modes of Use in Thermal Reactors 44 2.4.6 Plutonium in Fast Reactors 44 2.4.7 Plutonium in Thorium-Burning Thermal Reactors 46 2.4.8 The Present Situation 48 2.4.9 Core Physics Calculations 48 2.5 Economics of Plutonium Recycle 52 2.5.1 General 52 2.5.2 Economic Methodology 52 2.5.3 Basic Assumptions 56 2.5.4 The Costs of the Stages of the Nuclear Fuel Cycle 56 2.5.4. 1 General 56 2.5.4.2 Uranium Prices 56 2.5.4.3 Uranium Conversion 57 2.5.4.4 Enrichment 59 2.5.4.5 Uranium Oxide Fabrication Costs 59 2.5.4.6 Mixed Oxide Fuel Fabrication 60 2.5.4.7 Interim Spent Fuel Storage 62 2.5.4.8 Fuel Transportation Costs 62 2.5.4.9 Reprocessing Costs 62 2.5.4.10 Plutonium and Uranium Credits 63 2.5.4.11 Plutonium Storage and Americium Removal Costs 64 2.5.4.12 Plutonium Transport Costs 64 2.5.4.13 Spent Fuel Disposal 64 2.5.4.14 Trends in Costs 65 2.6 Fuel Cost Illustrations and Sensitivities 65 2.6.1 Introduction 65 2.6.2 Cost Comparisons 68 2.6.2.1 Case A - Free Plutonium 68 2.6.2.2 Case B - Plutonium charged at recovery cost 71 2.6.3 The Effect of MOX Fuel Burn-Up 73 2.6.4 Plutonium Decay 73 2.6.5 Indifference Values 73 2.7 Other Sensitivities 74 2.7.1 Uranium Sources 74 6 2.7.1.1 With "free" plutonium 74 2.7.1.2 Plutonium charged with recovery costs 74 2.7.2 Discount Rates 74 2.7.3 Uranium Dioxide Fabrication Costs 75 2.7.4 Plutonium from Higher Burn-Up Fuels 75 2.8 Fuel Reloads and Systems Savings 75 2.9 Other Factors Affecting Fuel Cycle Choice 77 2.9.1 Introduction 77 2.9.2 Strategic Factors 77 2.9.3 Ecological Factors 81 2.9.4 Institutional Factors 81 2.9.5 Safety 82 Part 3. THE CURRENT STATUS OF MOX FUEL 83 3.1 Overview 83 3.2 National Plans 85 3.3 A Plutonium Market 87 Part 4. SUMMARY, DISCUSSION AND CONCLUSIONS 88 REFERENCES 91 ANNEXES: A Spent Fuel Storage 94 B Mox Use and Thermal Reactor Safety 95 C The Reference PWR 97 D Multiple Plutonium Recycling in Pressurised Water Reactors 99 E Economic Methodology 102 F National Views on Plutonium Use - Country Annexes 103 G Equivalent Plutonium 120 H Fuel Cost Calculations - Methods. Assumptions and Back-Up Data 122 Appendix HI The Equivalence of Plutonium Pricing and Credits 138 7 I Glossary of Terms: English/French Dictionary 140 J Bibliography 151 K Members of the Working Group on Strategies for Plutonium Utilisation 158 LIST OF FIGURES: In Main Text 1. Simplified reaction chain for production of Pu236 and Pu238 18 2. Decay modes of transuranic elements 20 3.a) Neutron cross-sections for uranium to fission 22 b) Neutron cross-sections for uranium to capture a neutron 22 4. Average number of neutrons released from fission 28 5. Neutron yield per neutron absorbed 29 6. Plutonium recycling options 33 7. Decay of fissile plutonium with time 36 8. Build-up of americium in plutonium with time 37 9. Once-through MOX fuel 45 10. Plutonium production and recycle, MOX fuel reprocessed 45 11. Comparative annual plutonium fuel requirements for 100 % MOX fuelled PWR and for FBR ... 47 12. Fuel relationships 49 13. The stages for the uranium oxide and mixed oxide fuel cycles for the PWR 53 14. Possible cost allocations for the uranium oxide and mixed oxide fuel cycles for the PWR 54 15. Simplified stage costs for U0 and MOX fuels 55 2 16. Lead and lag times 66 17. Illustrative costs per kg for equilibrium replacement PWR fuels (using free plutonium) 67 18. Illustrative costs per kWh for equilibrium replacement PWR fuels (using free plutonium) 67 19. Sensitivity of fuel costs to uranium price, SWU costs and MOX fabrication costs (using free plutonium). Assumed burn-up 33 000 MWd/t 69 20. Avoided plutonium storage costs for 33 000 MWd/t LWR fuel 70 21. Sensitivity of plutonium indifference value to enrichment price and MOX fabrication costs 72 22. Economic comparison of reload costs, using free plutonium (discount rate 0 %) 76 23. Economic comparison of reload costs, using free plutonium (discount rate 5 %) 76 24. Projected Annual Spent Fuel Arisings in OECD Countries to 2000 84 25. Plutonium (Total) Contained in Annual Spent Fuel Arisings in OECD Countries to 2000 86 26. Annual Plutonium Recovery Capacity in OECD Countries to 2000 86 8