NUCLEAR ENERGY ENCYCLOPEDIA

WILEY SERIES ON ENERGY

NUCLEAR ENERGY ENCYCLOPEDIAScience, Technology, and Applications

Edited by

STEVEN B. KRIVIT, Editor-in-ChiefNew Energy TimesSan Rafael, CA, USA

JAY H. LEHR, Series EditorThe Heartland InstituteChicago, IL, USA

THOMAS B. KINGERY, Editor

A JOHN WILEY & SONS, INC., PUBLICATION

Copyright 2011 by John Wiley & Sons, Inc. All rights reserved.

Published by John Wiley & Sons, Inc., Hoboken, New Jersey.Published simultaneously in Canada

No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical,photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without eitherthe prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc.,222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 750-4470, or on the web at www.copyright.com. Requests to the Publisher forpermission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax(201) 748-6008, or online at http://www.wiley.com/go/permission.

Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representationsor warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantabilityor fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategiescontained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shallbe liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages.

For general information on our other products and services or for technical support, please contact our Customer Care Department within the UnitedStates at (800) 762-2974, outside the United States at (317) 572-3993 or fax (317) 572-4002.

Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic formats. For moreinformation about Wiley products, visit our web site at www.wiley.com.

Library of Congress Cataloging-in-Publication Data:

Nuclear energy encyclopedia: science, technology, and applications (Wiley series on energy)/Steven B. Krivit, editor-in-chief;Jay H. Lehr, series editor.

p. cm.Includes index.ISBN 978-0-470-89439-2 (v. 1 : cloth)

1. Power resources–Encyclopedias. 2. Complete in 5 v. Cf. Wiley encycl. of energy WWW site: xh072011-01-21 I. Krivit, Steven II. Lehr, Jay H., 1936– B. III. Title: Encyclopedia of energy.

TJ163.16.W55 2011621.04203–dc22

2010053086

Printed in Singapore

oBook ISBN: 978-1-118-04349-3ePDF ISBN: 978-1-118-04347-9ePub ISBN: 978-1-118-04348-6

10 9 8 7 6 5 4 3 2 1

CONTENTS

Preface ixSteven B. Krivit

Introduction xiJay Lehr

Contributors xiii

Nuclear Fission: Glossary and Acronyms xvK. Anantharaman, P.R. Vasudeva Rao, Carlos H. Castano, and Roger Henning

Nuclear Fusion: Glossary and Acronyms xixLester M. Waganer

PART I GENERAL CONCEPTS 1

1 Nuclear Energy: Past, Present, and Future 3Jay Lehr

2 Benefits and Role of Nuclear Power 7Patrick Moore

3 Early History Of Nuclear Energy 15Roger Tilbrook

4 Early Commercial Development of Nuclear Energy 23Roger Tilbrook

5 Basic Concepts of Thermonuclear Fusion 31Laila A. El-Guebaly

6 Basic Concepts of Nuclear Fission 45Pavel V. Tsvetkov

7 Oklo Natural Fission Reactor 51L.V. Krishnan

v

vi CONTENTS

8 Electrical Generation from Nuclear Power Plants 57Pavel V. Tsvetkov and David E. Ames II

9 Nuclear Energy for Water Desalination 65Saly T. Panicker and P.K. Tewari

10 Nuclear Energy for Hydrogen Generation 71Alistair I. Miller

PART II NUCLEAR FISSION 77

11 Uranium-Plutonium Nuclear Fuel Cycle 79Shoaib Usman

12 Global Perspective on Thorium Fuel 89K. Anantharaman and P.R. Vasudeva Rao

13 Design Principles of Nuclear Materials 101Baldev Raj and M. Vijayalakshmi

14 Nuclear Fuel Reprocessing 121Carlos H. Castano

15 Safety of Nuclear Fission Reactors: Learning from Accidents 127J.G. Marques

16 Spent Fuel and Waste Disposal 151Clifford Singer and William R. Roy

17 Fission Energy Usage: Status, Trends and Applications 159Pavel V. Tsvetkov

PART III FISSION: BROAD APPLICATION REACTORTECHNOLOGY 165

18 Light-Water-Moderated Fission Reactor Technology 167J’Tia P. Taylor and Roger Tilbrook

19 CANDU Pressurized Heavy Water Nuclear Reactors 175Rusi P. Taleyarkhan

20 Graphite-Moderated Fission Reactor Technology 187Pavel V. Tsvetkov

21 Status of Fast Reactors 193Baldev Raj and P. Chellapandi

22 Review of Generation-III/III+ Fission Reactors 231J.G. Marques

23 Tomorrow’s Hope for a Pebble-Bed Nuclear Reactor 255Jay Lehr

24 Hydrogeology and Nuclear Energy 257Roger Henning

CONTENTS vii

PART IV FISSION: GEN IV REACTOR TECHNOLOGY 271

25 Introduction to Generation-IV Fission Reactors 273Harold McFarlane

26 The Very High Temperature Reactor 289Hans D. Gougar

27 Supercritical Water Reactor 305James R. Wolf

28 The Potential Use of Supercritical Water-Coolingin Nuclear Reactors 309Dr. Igor Pioro

29 Generation-IV Gas-Cooled Fast Reactor 349J’Tia P. Taylor

30 Generation-IV Sodium-Cooled Fast Reactors (SFR) 353Robert N. Hill, Christopher Grandy, and Hussein Khalil

PART V THERMONUCLEAR FUSION 365

31 Historical Origins and Development of Fusion Research 367Stephen O. Dean

32 Plasma Physics and Engineering 371Francesco Romanelli

33 Fusion Technology 389Lester M. Waganer

34 ITER—An Essential and Challenging Step to FusionEnergy 399Charles C. Baker

35 Power Plant Projects 405Laila A. El-Guebaly

36 Safety and Environmental Features 413Lee Cadwallader and Laila A. El-Guebaly

37 Inertial Fusion Energy Technology 421Rokaya A. Al-Ayat, Edward I. Moses, and Rose A. Hansen

38 Hybrid Nuclear Reactors 435Jose M. Martinez-Val, Mireia Piera, Alberto Abanades, and Antonio Lafuente

39 Fusion Maintenance Systems 457Lester M. Waganer

40 Fusion Economics 469Lester M. Waganer

viii CONTENTS

PART VI LOW-ENERGY NUCLEAR REACTIONS 479

41 Development of Low-Energy Nuclear Reaction Research 481Steven B. Krivit

42 Low-Energy Nuclear Reactions: A Three-Stage Historical Perspective 497Leonid I. Urutskoev

43 Low-Energy Nuclear Reactions: Transmutations 503Mahadeva Srinivasan, George Miley, and Edmund Storms

44 Widom–Larsen Theory: Possible Explanation of LENRs 541Joseph M. Zawodny and Steven B. Krivit

45 Potential Applications of LENRs 547Winthrop Williams and Joseph Zawodny

PART VII OTHER CONCEPTS 551

46 Acoustic Inertial Confinement Nuclear Fusion 553Rusi P. Taleyarkhan, Richard T. Lahey Jr., and Robert I. Nigmatulin

47 Direct Energy Conversion Concepts 569Pavel V. Tsvetkov

Index 581

PREFACE

Steven B. Krivit

WE WERE ONCE TERRIFIED OF FIRE, TOO

The discovery of fire 790,000 years ago must have beenterrifying to cave men and women [1]. Since that time,many people have died and much property has beendestroyed as a result of chemical energy released throughfire. Nevertheless, that chemical energy found its place inthe world, providing great benefits, and most people take itfor granted.

In stark contrast, humankind began to develop and usenuclear energy less than a hundred years ago. Accordingto a 2008 report from the International Energy Agency,nuclear energy provides 13.5% of worldwide electricity [2].

On March 11, 2011, just before we went to press,several of the Fukushima, Japan, nuclear power plants weredamaged from a 9.0 magnitude earthquake and a 10-mtsunami. The event dominated headlines and, with somehelp from the mass media, re-sparked the public’s fears ofnuclear energy. Some people may look back at Fukushimaand consider it a nuclear disaster; others may consider it anuclear engineering success story, considering the parts ofthe reactors that did stand up to natural disasters beyondthose for which they were designed.

Some members of the public have the misinformed viewthat radiation has no place in a safe and healthy world.Radiation has always been around us. It comes from avariety of natural sources, and it is widely used in medicine.

The difference between radiation levels that pose asignificant health risk and radiation levels that posenegligible or no risks has everything to do with emissionrate, concentration, dispersion, distance from, and durationof exposure. Other key factors include the unique propertiesof each isotope, such as how it affects the body and howlong it remains radioactive.

In light of the public’s fear, examining how nuclearenergy has fared in terms of safety and environment isuseful. Remembering that a perfect energy solution forelectricity production and transportation does not exist is

also useful. Chemical energy and hydroelectric energy havenot been without accidents and deaths. Solar and otherrenewables may have fewer health and environmental risks,but excluding hydroelectric, they provide only 2.8% ofelectrical power worldwide; they have not demonstratedgreater capacity for baseload electrical production.

The public’s fear of nuclear energy is an undercurrentthat affects all actions related to this industry. This fearmust be addressed. Doing that requires exploring the risksand consequences of nuclear energy and other energytechnologies. The perceived relationship between nuclearenergy and nuclear weapons also contributes to the public’sfear.

The 1986 Chernobyl nuclear accident—by far theworst—is most instructive. In 2006, the Chernobyl Forum,an organization comprising the International Atomic EnergyAgency, the World Health Organization, the World Bank,and five United Nations organizations working in the areasof food, agriculture, environment, humanitarian affairs, andradiation effects, published an authoritative analysis ofthe health, environmental, and socioeconomic impacts ofChernobyl [3].

The report concluded that 31 emergency workers diedas a direct consequence of their response to the Chernobylaccident. The Forum was unable to reliably assess theprecise numbers of fatalities by radiation exposure. The bestthey were able to do was speculate and make conjecturebased on the experience of other populations exposedto radiation. They also wrote that small differences intheir assumptions could lead to large differences in theirpredictions. By 2002, 15 deaths were reported from among4000 people exposed to radiation and diagnosed withthyroid cancer. These data are in stark contrast to a numberof other poorly referenced sources, which have speculatedon large numbers of radiation-related deaths.

Concerning environmental impact, the report said thatthe majority of the contaminated territories are nowsafe for settlement and economic activity and that the

ix

x PREFACE

Chernobyl Exclusion Zone and a few limited areas willhave restrictions for many decades.

In August 1975, the Banqiao hydroelectric dam inwestern Henan province, China, failed as a result ofTyphoon Nina, which produced floods greater than thedam was designed to withstand. According to EncyclopediaBritannica , 180,000 people died [4].

On April 20, 2010, the Deepwater Horizon offshore oildrilling rig failed and caused 200 million gallons of crudeoil to leak into the Gulf of Mexico, according to “PBSNews Hour.” The leak was out of control for 3 months and11 men died.

One billion gallons of oil from 21 disasters have beenspilled in the oceans since 1967, according to Infoplease [5].

In the United States alone, 260 workers have lost theirlives in 21 coal mining accidents since 1970, according tothe United States Mine Rescue Association [6].

In Nigeria, on October 18, 1998, a natural gas pipelineexplosion took the lives of 1082 people, according toAgence France-Presse [7].

Members of the public would benefit from scrutinizingthe comparative safety and track record of clean, emission-free nuclear energy. They would also benefit from learningthe basic concepts and principles of nuclear energyproduction.

The nuclear industry would know that the public is nevergoing to believe—nor should it—that nuclear accidentscan’t happen. However, it would do well to hear the public’sfears and help people understand that nuclear energy hassome risks and hazards.

Governments would also do well to show how they areprepared to protect their citizens with effective regulationto minimize radiological emergencies as well as effectiveresponse strategies when they occur.

In the absence of the public’s understanding of thefacts, fear mongers and sensationalist media will surelyfill in.

Nuclear energy is certainly not perfect, but the effortsof researchers and industry are significant and crucial.The innovative scientific research and engineering designsshown in this book reflect decades of technologicaldevelopments in a variety of nuclear applications that areready to be put to use.

REFERENCES

1. The Hebrew University of Jerusalem, October 27, 2008 pressrelease. http://www.huji.ac.il/cgi-bin/dovrut/dovrut_search_eng.pl?mesge122510374832688760.

2. International Energy Agency’s Key World Energy Statistics2010, Updated February 2011. http://www.iea.org/publications/free_new_desc.asp?pubs_ID=1199.

3. The Chernobyl Forum, Chernobyl’s Legacy: Health, Envi-ronmental and Socio-Economic Impacts. http://www.iaea.org/Publications/Booklets/Chernobyl/chernobyl.pdf.

4. Encyclopedia Britannica, Typhoon Nina–Banqiao dam fail-ure. http://www.britannica.com/EBchecked/topic/1503368/Typhoon-Nina-Banqiao-dam-failure.

5. Infoplease, Oil Spills and Disasters. http://www.infoplease.com/ipa/A0001451.html.

6. United States Mine Rescue Association, Historical Data onMine Disasters in the United States. http://www.usmra.com/saxsewell/historical.htm.

7. Agence France-Presse, A History of Blasts, in USA Today ,Nigerian pipeline blast kills up to 200. http://www.usatoday.com/news/world/2006-05-12-nigeria_x.htm.

INTRODUCTION

Jay Lehr

This book marks a significant milestone in the reintro-duction of a set of mature nuclear technologies. It alsointroduces new ideas that expand the frontiers of nuclearscience research. It is a timely resource for a world that isawakening to a nuclear renaissance.

Oddly, nuclear energy needs to be reintroduced as if itwere a new technology. For a variety of reasons, whichvary slightly from nation to nation, the capabilities andcapacities of nuclear energy have been under-recognized.In the United States, for example, it supplies 20% of theelectric power even though no new nuclear power plant hasbeen designed, approved, and built in the United States indecades.

Nuclear power is a form of terrestrial energy, the sameprocess that heats the center of our earth to 7,000◦F.Radioactivity is a natural phenomenon, and indeed, fuelfor nuclear power plants comes from natural resources.The concentration of power in the nucleus of the atomis incredible: The disintegration of a single uraniumatom produces 2 million times more energy than thatproduced by breaking a single carbon-hydrogen bond incoal, oil, or natural gas when burned. Nuclear power isan underappreciated marvel of modern technology thatharnesses and amplifies a natural process to help satisfycivilization’s need for energy.

A 1,000-megawatt coal-fired power plant requires 110rail cars of coal each day, while an equally powerful nuclearplant requires a single tractor-trailer to deliver new fuelrods once every 18 months. Solar or wind power requires200 times more land than either coal- or nuclear-poweredplants do.

Three decades ago, the average efficiency of nuclearplants was barely 50%, which is to say that they wereputting out their rated capacity of energy only half thetime. Today, that efficiency has climbed to 94%. Althoughdecades have passed since a nuclear power plant has beenconstructed in the United States, these reactors produce

25% more power with the same 104 operating plants todaythan they did 20 years ago.

The real dangers of nuclear power to humans and theenvironment are vastly different from the propaganda-based exaggerations that have been commonplace in recentdecades. Every energy industry has its risks and failures,whether oil spill disasters or coal mine disasters. Prudenceand wisdom dictate that decision makers consider the fullspectrum of risk and reward in any energy endeavor; thisbook will help provide sound facts for that purpose.

Future reactors will be even safer than they are todayand more cost effective, as well; much has been learnedfrom both successes and failures worldwide.

The United States, at one time a leader in nucleartechnology, is lagging in new plant development. Thelengthy time required for licensing and construction inthe United States remains a significant obstacle to seriousinvestment. According to the Nuclear Energy Institute,applications for 26 new nuclear units are pending withfederal regulators, but the most optimistic outlook suggeststhat only four plants may be built by 2020.

On the other hand, the International Atomic EnergyAgency reports that 34 nuclear power plants are underconstruction in 12 countries besides the United States,including seven in Russia, six in China, and six in India.Many more are on their drawing boards.

Many publications have touted a rebirth of nuclearenergy in the United States, but a closer reading oftenreveals that such support and predictions are tepid at best.Often, the greatest opposition to the clean energy of nuclearpower has come from people who maintain a philosophythat more available energy and the progress it will allowwill have adverse effects on the environment. In fact, weknow that when societies increase their standard of livingthrough economic activity, then and only then can theyafford to focus on improving their environment.

During the last few decades, significant misinformationhas been propagated worldwide about nuclear energy, often

xi

xii INTRODUCTION

unknowingly by people with good intentions and care forthe environment, although without access to reliable facts.This book helps to bridge that gap.

For decades, nuclear researchers and engineers havebeen diligently developing and refining new designs andtechnology. Future-generation nuclear technology will bemore passive, no longer requiring coolant to be pumpedinto vessels in the event of excessive heat. Instead, coolantwill be stored at higher elevations, where gravity can dothe work.

New plants will have a life of 60 years, spreading theiramortized costs. Modular construction will allow quickerand less-expensive assembly. Inherently safe systems, suchas the pebble-bed reactor, require fewer safety featuresbecause the systems cannot achieve dangerous levels ofheat when malfunctions occur. In the case of the pebblebeds, the uranium fuel is encased in ceramic spheres thesize of tennis balls, and the melting point of the ceramic iswell above the level of any heat that can be generated bythe uranium.

Waste disposal is not a problem, although it gets themost headlines. Even most critics agree that existing usedfuel rods can stay where they are for another 50 or 100years until permanent storage is determined. In the UnitedStates, recycling used fuel has been significantly at oddswith the scientific, technical, and even political reality. It isin great need of overhaul.

In 1977, President Jimmy Carter, through a misguideddirective, decided that the United States would not repro-cess civilian nuclear fuel. According to A. David Rossin, ascholar with the Center for International Security and ArmsControl at Stanford University, Carter relied on his advisorsand put reprocessing of spent nuclear reactor fuel on hold inthe United States. The small amount of mistakenly poten-tially weapon-grade plutonium produced on reprocessingcaused Carter to stop the U.S. program [1]. This decisionhad several negative consequences.

According to Rossin, Carter hoped that, by settingthis example, the United States would encourage othernations to follow its lead. Carter was naive to think thatbanning reprocessing in the United States, even if basedon substantive technical facts, would make the worldsafer. Why would rogue nations or terrorist groups followCarter’s example? That peaceful nuclear states wouldvoluntarily follow Carter’s example to waste nuclear fuelwas unrealistic.

As time has shown, other nations have not followed theUnited States. On October 12, 2010, India announced it haddeveloped its fast breeder reactor technology sufficiently toexport it to the world.

Most countries are far more fuel-efficient than the UnitedStates and have a fraction of the waste to manage thatthe United States does. Thus, while U.S citizens diligentlystrive to recycle their plastic, papers, and many other naturalresources, France, for example, gets 80% of its electricityfrom nuclear power and uses 95% of the available fuel,leaving that country with only 5% waste to manage.

The United States pays a double penalty as a result ofCarter’s directive, because it uses only 5% of the fuel andwastes 95% of it. Thus, the United States is one of the leastresponsible nations in nuclear fuel recycling.

There is even greater hope for the future with fastreactors, described in this book, that can use nuclearwastes from a variety of sources as fuel. They are ableto unlock energy in waste because they can burn plutoniumand neptunium and other materials that are byproducts ofcurrent nuclear reactors.

Fast reactors under development in the United Statescould supply all of the nation’s energy needs for 70 yearsusing only nuclear waste in storage today. While costs perkilowatt of capacity will exceed all other nuclear plants,they likely will drop significantly after a few fast reactorscome on line.

Nuclear power is progressing technologically andsocially, but the battle for the future of mankind’s energyis far from won. This book aims to fill a crucial role: toeducate industry, policymakers, students, and the publicthat nuclear energy is the safest and most plentiful formof energy to power the future of civilization. This bookoffers the most up-to-date collection of all we know aboutthe future of nuclear energy around the world, and it is abright future indeed.

ACKNOWLEDGMENTS

The editors would like to thank Bob Esposito and MichaelLeventhal for their work in producing this book, and JohnWiley & Sons, Inc., for publishing it. Steven Krivit wouldalso like to thank the sponsors of New Energy Institute fortheir support of this project.

We deeply appreciate the contributions of the manyexperts who, through their work, are helping to advancenuclear science and technology worldwide.

REFERENCE

1. A. David Rossin, U.S. Policy on Spent Fuel Repro-cessing: The Issues . http://www.pbs.org/wgbh/pages/frontline/shows/reaction/readings/rossin.html.

CONTRIBUTORS

Dr. Alberto Abanades, Institute of Nuclear Fusion-UPM,c/Jose Gutierrez Abascal, 2, Madrid, Spain

Dr. Rokaya A. Al-Ayat, Lawrence Livermore NationalLaboratory, 7000 East Avenue, L-580, Livermore, CA,USA

Dr. David E. Ames II, Texas A&M University, Departmentof Nuclear Engineering, 129 Zachry Engineering Center,3133 TAMU, College Station, TX, USA

Mr. K. Anantharaman, Reactor Design and DevelopmentGroup Trombay, Bhabha Atomic Research Centre,Mumbai, Maharashtra, India

Dr. Charles C. Baker, Sandia National Laboratories,Principal Editor-Fusion Engineering and Design, Albu-querque, NM, USA

Mr. Lee Cadwallader, Idaho National Laboratory, IdahoFalls, ID, USA

Carlos H. Castano, Missouri University of Science andTechnology, Nuclear Engineering, 222 Fulton Hall, 1870Miner Circle, Rolla, MO, USA

Dr. P. Chellapandi, Indira Gandhi Centre for AtomicResearch, Kalpakkam, TN, India

Dr. Stephen O. Dean, Fusion Power Associates, 2 Profes-sional Drive Suite 249, Gaithersburg, MD, USA

Dr. Laila A. El-Guebaly, Fusion Technology Institute,431, Engineering Research Building, 1500 EngineeringDrive, Madison, WI, USA

Dr. Hans D. Gougar, Idaho National Laboratory, IdahoFalls, ID, USA

Mr. Christopher Grandy, Argonne National Laboratory,9700 S. Cass Avenue, Argonne, IL, USA

Ms. Rose A. Hansen, Lawrence Livermore NationalLaboratory, 7000 East Avenue, L-471 Livermore, CA,USA

Dr. Roger Henning, Nuclear and Hydrogeologic SupportServices, 2120 Crooked Pine Drive, Las Vegas, NV,USA

Dr. Robert N. Hill, Argonne National Laboratory, 9700 S.Cass Avenue, Argonne, IL, USA

Dr. Hussein Khalil, Argonne National Laboratory, NuclearEngineering Division, 9700 S. Cass Avenue; Bldg.208 Argonne, IL, USA

Mr. Lakshminarayana Venkata Krishnan, Indira GandhiCentre for Atomic Research, B6, Madhurima Apart-ments, 32, Conransmith Road, Gopalapuram, Chennai,TN, India

Mr. Steven B. Krivit, New Energy Times, 369-B ThirdStreet; Suite 556, San Rafael, CA, USA

Dr. Antonio Lafuente, Institute of Nuclear Fusion-UPM,c/Jose Gutierrez Abascal, 2, Madrid, Spain

Dr. Richard T. Lahey Jr., Rensselaer Polytechnic Insti-tute, MANE - NES Bldg., 110 8th Street, Troy, NY,USA

Dr. Jay Lehr, The Heartland Institute, 19 South LaSalleStreet #903, Chicago, IL, USA

Dr. J.G. Marques, Instituto Tecnologico, Estrada Nacional10, Sacavem P-2686-953; Centro de Fısica Nuclear,Universidade de Lisboa, 1649-003 Lisboa, Portugal

xiii

xiv CONTRIBUTORS

Dr. Jose M Martinez-Val, Institute of Nuclear Fusion-UPM, c/Jose Gutierrez Abascal, 2 Madrid, Spain

Dr. Harold McFarlane, Idaho National Laboratory, IdahoFalls, ID, USA

Dr. George Miley, University of Illinois at Urbana-Champaign, Fusion Studies Laboratory, 103 S Goodwin,Urbana, IL, USA

Dr. Alistair I. Miller, Atomic Energy Canada Ltd.,8 Darwin Crescent, Deep River, ON, Canada

Dr. Patrick Moore, Greenspirit Strategies Ltd., 873 BeattyStreet #305, Vancouver BC V6B 2M6, Canada

Dr. Edward I. Moses, Lawrence Livermore NationalLaboratory, 7000 East Avenue, L-466, Livermore, CA,USA

Dr. Robert I. Nigmatulin, Russian Academy of Sciences,Russia

Ms. Saly T. Panicker, Desalination Division, BhabhaAtomic Research Centre, Trombay, Mumbai, Maharash-tra, India

Dr. Mireia Piera, Ingenieria Energetica, UNED ETSII-Dp,c/Juan del Rosal, 12, Madrid, Spain

Dr. Igor Pioro, University of Ontario Institute of Technol-ogy, Faculty of Energy Systems and Nuclear Science,2000 Simcoe Street North, Oshawa, Ontario, Canada

Dr. Baldev Raj, Indira Gandhi Centre for AtomicResearch, Kalpakkam, TN, India

Dr. P.R. Vasudeva Rao, Indira Gandhi Centre for AtomicResearch, Kalpakkam, TN, India

Dr. Francesco Romanelli, JET-EFDA Culham ResearchCenter, Abingdon OX14 3 DB, UK

Dr. William R. Roy, University of Illinois at Urbana-Champaign, Department of Nuclear, Plasma, and Radi-ological Engineering, 216 Talbot Laboratory, MC-234,104 South Wright Street, Urbana, IL, USA

Dr. Clifford Singer, Department of Nuclear, Plasma,and Radiological Engineering, University of Illinois at

Urbana-Champaign, 216 Talbot Laboratory, MC-234,104 South Wright Street, Urbana, IL, USA

Dr. Mahadeva Srinivasan, Bhabha Atomic ResearchCentre (Retired), 25/15, Rukmani Road, KalakshetraColony, Besant Nagar, Chennai, TN, India

Dr. Edmund Storms, Kiva Labs, 2140 Paseo Ponderosa,Santa Fe, NM, USA

Prof. Rusi P. Taleyarkhan, Purdue University, Collegeof Engineering, 400 Central Drive, West Lafayette, IN,USA

Dr. J’Tia Taylor, Argonne National Laboratory, 9700 S.Cass Avenue, Argonne, IL, USA

Dr. P.K. Tewari, Bhabha Atomic Research Centre, Desali-nation Division, Trombay, Mumbai, Maharashtra, India

Mr. Roger Tilbrook, 86 White Oak Circle, St. Charles, IL,USA

Dr. Pavel V. Tsvetkov, Texas A&M University, Depart-ment of Nuclear Engineering, 129 Zachry EngineeringCenter, 3133 TAMU College Station, TX, USA

Dr. Leonid I. Urutskoev, Moscow State UniversityOf Printing Arts, State Atomic Energy Corporation“Rosatom”, Expert Dep. ul. Bolshaya Ordynka, 24/26,Moscow, Russia

Dr. Shoaib Usman, Missouri University of Science andTechnology, Mining & Nuclear Engineering, 222 FultonHall, 1870 Miner Circle, Rolla, MO, USA

Dr. M. Vijayalakshmi, Indira Gandhi Centre for AtomicResearch, Kalpakkam, TN, India

Mr. Lester M. Waganer, 10 Worcester Ct., O Fallon, MO,USA

Dr. Winthrop Williams, U.C. Berkeley, 2615 Ridge Rd.#D, Berkeley, CA, USA

Dr. James R. Wolf, Idaho National Laboratory, IdahoFalls, ID, USA

Dr. Joseph. M. Zawodny, NASA Langley ResearchCenter, MS-475, Hampton, VA, USA

NUCLEAR FISSION: GLOSSARY AND ACRONYMS

K. Anantharaman, P.R. Vasudeva Rao, Carlos H. Castano and Roger Henning

GLOSSARY

Burn-up A measure of energy extracted from nuclearreactor fuel. It is defined as the ratio of the thermalenergy released by nuclear fuel to mass of fuel materialconsumed. It is typically expressed as Gigawatt days perton of fuel (GWd/t).

Capture cross-section A measure of the probability thatan incident particle or photon will be absorbed by atarget nuclide.

Chain reaction Neutron-induced fission is a commonexample. The fission reaction produces neutrons thatcan sustain the reaction, thus forming a chain of linkedreactions. Gasoline combustion is an example fromchemistry. A spark initiates the combustion, resultingin a release of energy that is sufficient to propagate thereaction.

Cross-section of a nuclear reaction A measure of theprobability that a nuclear reaction will occur. It is theapparent or effective area presented by a target nucleusor particle to an oncoming radiation. The barn is thestandard unit for the cross section and is equal to10−24 cm2.

Enrichment Physical process of increasing the proportionof U235 to U238 material in nuclear fuel element, i.e.,increasing the fissile content. It is generally carried outby using high-speed centrifuges or by gaseous diffusionprocess.

Fast neutron Neutron released during fission, travelingat high velocity and having high energy (>1 MeV).

Fission cross-section The probability a reaction willoccur that will cause a nuclide to fission.

Fission product A residual nucleus formed in fission,including fission fragments and their decay products.

Fuel cycle All steps in the use of nuclear material asfuel for a nuclear reactor, including mining, purification,

isotopic enrichment, fuel fabrication, irradiation, storageof irradiated fuel, reprocessing, and disposal.

Fuel cycle—Open Spent fuel is removed from thereactor, cooled, and transferred to long-term dry storage.No attempt is made to recover the unused fissile material.

Fuel cycle—Closed Spent fuel is removed from reactorand after a cooling period, it is transferred for reprocess-ing. The fissile material is recovered for reuse and thefission products are separated for disposal. Reprocess-ing enables recycling of the fissile isotopes and reducesamount of waste to be disposed.

Half-life The time period required for half of the atomsof a particular radioactive isotope to decay.

Heavy water Water containing an elevated concentrationof molecules with deuterium (“heavy hydrogen”) atoms.It has chemical properties similar to that of ordinaryor light water, but neutronic properties are different.Heavy water absorbs fewer neutrons and is also a bettermoderator.

Isotope Different isotopes of an element have the samenumber of protons but different numbers of neutrons.Therefore, the isotopes of an element have differentatomic masses. For example, U235 and U238 areisotopes of uranium.

Neutron capture Absorption of a neutron by an atomicnucleus. A measure of the probability that a materialwill capture a neutron is given by the neutron capturecross-section, which depends on the energy of a neutronand on the composition of the material.

Nuclear fission The process of splitting a heavy nucleusinto two lighter nuclei, accompanied by the simultaneousrelease of a relatively large amount of energy andusually one or more neutrons. Fission is induced throughthe reaction of an incident radiation with the nucleus.Neutron-induced fission of uranium-235 is a commonexample. Considerable energy is released during thefission reaction, and this energy can be used to produce

xv

xvi NUCLEAR FISSION: GLOSSARY AND ACRONYMS

heat and electricity. Spontaneous fission is a type ofradioactive decay for some nuclides.

Nuclear fusion The process of forming a heavier nucleusfrom two lighter ones.

Scrub A substance used to absorb preferentially anotherin a different phase by providing a preferential chemicalreaction or state. Traditionally, the term has been usedto designate a liquid to retain gaseous exhausts from agas stream, but it is applied to other systems as well,including slurries and liquid-to-liquid retention.

Salting Providing extra ions necessary to carry out orimprove a particular chemical process. Usually theaddition of a salt with the proper ion is meant, butadding the ion in any form can be equally effective (e.g.,providing NO−

3 ions by addition of NaNO3 or HNO3).

Uranium-233 A fissile, manmade isotope of uranium. Itis created when thorium-232 captures a neutron throughirradiation. It has a half-life of 160,000 years and decaysby emitting alpha particles.

Uranium-235 Only fissile isotope of uranium occurringin nature (0.7% abundance). Uranium-235 has a half-lifeof 700 million years, and it can sustain a chain reaction.

Uranium-238 The most prevalent isotope (>99.3%) ofuranium in nature. It has a half-life of about 4,500million years. Uranium-238 emits alpha particles, whichare less penetrating than other forms of radiation.Uranium-238 cannot sustain a chain reaction, but it canbe converted by neutron capture to plutonium-239.

Plutonium-239 A heavy, radioactive, manmade fissileisotope of plutonium. It is the most common isotopeformed in a typical nuclear reactor formed by neutroncapture from U238 and yields much the same energy asthe fission of U235. Pu239 has a half-life of 24,400 yearsand decays by emitting alpha particles. The hazard fromPu-239 is similar to that from any other alpha-emittingradionuclides (Inhalation).

Thorium-232 Th-232 is most stable isotope of thorium,and nearly all natural thorium is Th-232. The isotopethorium-232 is stable, having a half-life of about14,000 million years, and undergoes alpha decay. Unlikeuranium, thorium does not contain any natural fissileisotope. Thorium-232 is not fissile itself, but it canabsorb slow neutrons to convert it into U233, which isfissile.

Voloxidation If tritium (3H) needs to be separated fromspent fuel, it is better to do it before the fuel is dissolved,since the tritium would then be isotropically distributedwith all the hydrogen in water, solvents, and nitric acid,making its separation much harder. Voloxidation is aprocess developed by ORNL in which fuel after shearingis then oxidized in a rotating furnace to convert UO2 toU3O8. The latter is less dense, causing the fuel to swell,

pulverizing the ceramic fuel and causing the releaseof occluded gasses. The released gasses (Kr, Xe, etc.)can then be collected, and particularly tritium can thenbe oxidized and removed as almost pure ultra-heavywater (3H2O), all carried out before the fuel is dissolved[M. Benedict, T. Pigford, and H. W. Levi, Chapter 10:Fuel reprocessing, In Nuclear Chemical Engineering .McGraw-Hill, New York, 1981, pp. 458–459, 476].

ACRONYMS

Abbreviation Expansion

AEA Atomic Energy Act of 1954AECL Atomic Energy of Canada Limited, CanadaAHWR Advanced Heavy Water ReactorALARA as low as is reasonably achievableBARC Bhabha Atomic Research Centre, Mumbai,

IndiaBORAX Boiling Reactor ExperimentBWR Boiling Water ReactorCANDU Canada Deuterium UraniumCEA Commissariat a l’Energie AtomiqueCERCLA Comprehensive Environmental Response,

Compensation, and Liability Act of 1980(Superfund)

CFR Code of Federal Regulations (U.S.)CP Chicago PileDOE (United States) Department of EnergyEBR Experimental Breeder ReactorEDF Electricite de FranceEFPD Effective Full Power DaysEPA (United States) Environmental Protection

AgencyEPRI Electric Power Research InstituteEuratom European Atomic Energy Community

(legally distinct from the European Unionbut has the same membership)

FBR Fast Breeder ReactorFBTR Fast Breeder Test ReactorFEPS features, events, and processesFUSRAP Formerly Utilized Sites Remedial Action

ProgramHEU Highly Enriched UraniumHLLW High Level Liquid WasteHLW high-level radiological wasteHTGR High Temperature Gas-cooled ReactorIAEA International Atomic Energy Agency

(independent organization but related tothe United Nations)

IGCAR Indira Gandhi Centre for AdvancedResearch, Kalpakkam, India

NUCLEAR FISSION: GLOSSARY AND ACRONYMS xvii

KAMINI Kalpakkam Mini ReactorLLW low-level radiological wasteLWBR Light Water Breeder ReactorLWR Light Water ReactorMOX Fuel Mixed Oxide FuelMSBR Molten Salt Breeder ReactorNEA Nuclear Energy AgencyNEPA National Environmental Policy Act of

1969NRC (United States) Nuclear Regulatory

AgencyNRTS National Reactor Testing StationNWPA Nuclear Waste Policy Act of 1982ORNL Oak Ridge National Laboratory, USAPDRP Power Demonstration Reactor

ProgramPHWR Pressurized Heavy Water ReactorPIE Post Irradiation ExaminationPRTRF Power Reactor Thorium Reprocessing

Facility

PUREX process Plutonium-URanium EXtractionprocess

PURNIMA Plutonium based Indian researchreactor (now dismantled)

PWR Pressurized Water ReactorRCRA Resource Conservation and Recovery

Act of 1976SNF spent nuclear fuelSSC structures, systems, or componentsTBP Tri-n-Butyl Phosphate solventTHOREX process THORium-uranium EXtraction

processTRU transuranic radiological wastesUMTRCA Uranium Mill Tailings Radiation

Control Act of 1978USAEC United States Atomic Energy

CommissionWIPP Waste Isolation Pilot Plant (operated

by DOE).

NUCLEAR FUSION: GLOSSARY AND ACRONYMS

Lester M. Waganer

GLOSSARY

Availability, Plant availability This metric is a ratio ofthe hours the plant is available for full power operationdivided by the total annual hours. Plant availability isaffected by the scheduled maintenance periods and theunscheduled maintenance periods. These maintenanceperiods are governed by maintainability, reliability, andinspectability.

Advanced (fusion) fuels The D-T fusion reaction is theleast demanding reaction, but other fuel combinationsare possible that have less energetic neutrons and morecharged particles, which enables longer first wall andblanket lifetimes and the possibility of direct conversioninto electricity with higher conversion efficiencies.

Blanket The blanket is the power- and fuel-producingcomponent within the power core. The “blanket” namehas been adopted to signify that the plasma is almostfully enveloped in a blanketing component. In the earlyand some present day fusion experiments, the blanketswere only shielding blankets in the sense that theycaptured the plasma thermal and neutron energy, butdid not have any tritium breeding function. For thefew experiments fueled with D-T, sufficient tritium fuelcould be externally supplied for the limited duty cycleoperation. As the duty cycle and the power level onfuture fusion facilities increase, there will be a need toprovide a substantial, steady-state supply of tritium. Thisrequires the blanket to be tritium breeding, containingeither lithium or a lithium compound. Two designconcepts are being pursued, solid and liquid breederblankets. As the designs move toward power plants, theblanket must operate with higher internal temperaturesto enable higher thermal conversion efficiencies. In thepresent designs, the blanket also supports the first wall.

Burn-up, Burn-up fraction It is the fraction of the fusionfuel elements that are fused to release the nuclear energy.

The burn-up fraction is used to determine the through-put of the fuel required to achieve the desired fusionpower level.

Capture cross-section A measure of probability that anincident particle/photon will be absorbed by a targetnuclide.

Constant dollars An economic analysis with constantdollars assumes that the purchasing power of thedollar remains constant throughout the constructionperiod—the cost for an item measured in money withthe general purchasing power as of some reference date.Hence, there is no inflation. However, there are costsassociated with the true (or real) interest value. This willnot be a realistic situation in the actual world as thereare always inflationary (or deflationary) effects, but this“constant dollar” analysis provides a more easily under-stood, comparative economic metric that avoids makingthe assumptions about future inflationary/deflationaryeffects. The rate of interest is usually in the range of3% to 6% without inflation.

Divertor The divertor is a plasma-facing subsystem,like the first wall. The divertor has a specializedfunction to intercept the energetic plasma particles ofelectrons, protons, alpha particles (fusion ash), and othertrace impurity elements that are swept out along themagnetic field lines at the plasma magnetic X-point(s).The magnetic geometry of tokamaks can have one ortwo regions where the confining magnetic fields cross,allowing the energetic particles to escape. Like the firstwall, tungsten armor will be required to provide adequatecomponent lifetime. It is highly desired for the divertorlifetime to be (nearly) the same as the first wall andblanket so both subsystems can be removed and replacedat the same time. Thus, the divertor armor must bemuch more robust than the first wall armor. The divertormodules are located at the bottom (for the single-nulldivertor) or at the top and bottom (for the double-nulldivertor) of the power core.

xix

xx NUCLEAR FUSION: GLOSSARY AND ACRONYMS

D-T fusion (reaction) The fusing of the two light nucleiof deuterium (D) and tritium (T) is the least demandingfusion reaction resulting in the creation of a 3.52 MeValpha particle and a 14.07 MeV neutron, resultingin an energy increase of 17.59 MeV. Other fusionfuel combinations are possible, called advanced fuels,because these combinations require more demandingplasma conditions.

Lithium enrichment Physical process of increasing theproportion of lithium-6 to lithium-7 isotopes in blanketbreeding materials.

First wall In most current experiments and postulatedpower plant-relevant facilities, the outer edges of thehigh temperature fusion plasma (∼100 million ◦C) areonly a few centimeters away from the first solid surface,the first wall, which protects the power/fuel-producingblanket and is the largest plasma-facing component.The current best candidates for underlying first wallstructural materials are ferritic steels or silicon carbidecomposites. The current thinking is that the candidatefirst wall materials may not be sufficiently robust tohandle the intense heating and occasional bursts ofparticle flux to last the required operational time. Tohave additional design margin, a thin layer of tungstenis being considered as an armor material because it ismore robust against high heat and particle sputteringwith low tritium retention. To accommodate the sizabledifferential thermal expansion, the tungsten coating willprobably be segmented. It will have to be brazed ormechanically attached to the basic first wall to ensureadequate thermal heat conduction.

Fusion cross-section The probability a reaction willoccur that will cause two light nuclides to fuse.

Half-life The time in which one half of the atoms of aparticular radioactive substance disintegrate into anothernuclear form. Measured half-lives vary from a fractionof a second to billions of years.

Heating and current drive The plasma is heated tosome degree by the flowing toroidal current, butadditional heating is required to reach the necessaryfusion temperatures. This is accomplished by radiofrequency (RF) heating or maybe neutral beam (NB)subsystems. The interior solenoidal coils will providethe initial toroidal current formation, but RF subsystemswill provide the continuing current drive for sustainedsteady-state operation.

Heavy water Water containing significantly more thanthe natural proportions (one in 6,500) of heavy hydrogen(deuterium, D) atoms to ordinary hydrogen atoms. It haschemical properties similar to that of ordinary or lightwater but different neutronic properties. Heavy water isused as a moderator in some reactors because it slows

down neutrons effectively and also has a low probabilityof absorption of neutrons.

Hohlraum target Hohlraum is a hollow cavity withwalls in radiative equilibrium with the radiant energywithin the cavity. The cavity has one or more holes toadmit the radiative beams that strike the inner hohlraumwalls, creating a bathing x-ray environment to heat andcompress the central fuel target.

Inertially confined fusion energy (IFE) A hot ionizedplasma is confined inertially with sufficient pressure,temperature, and time to fuse light elements to otherelements with a slightly decreased total mass that yieldsa net energy release. Confinement can be obtained usinglaser, light ion, or heavy ion beams directed toward smallfuel-containing targets in the center of a spherical orcylindrical chamber. Direct-drive targets require nearlysymmetric illumination, whereas indirect drive employsa target with a surrounding hohlraum where laser beamsenter the hohlraum from opposite sides.

Isotope Two or more forms (or atomic configurations)of a given element that have identical atomic numbers(the same number of protons in their nuclei) and thesame or very similar chemical properties but differentatomic masses (different numbers of neutrons in theirnuclei) and distinct physical properties. For example,Li-6 and Li-7 are isotopes of lithium, and deutritium(D) and tritium (T) are isotopes of hydrogen.

Liquid breeder blanket Liquid breeding blanketsemploy either stagnant or moving liquid metal contain-ing a lithium, lithium compound, or lithium eutecticto breed tritium. With the stagnant liquid breederoption, a separate coolant is used to remove the thermalenergy. With the moving liquid breeder option, theliquid breeder is the coolant. A separate coolant (suchas helium) may also be required to cool the structuralmaterial.

Low-activation materials High purity, specialty materi-als with a composition containing minimal impuritiesthat would transmute into long-lived radioactivity in thepresence of fusion neutrons.

Magnetic mirror The magnetic mirror was one of thefirst magnetic confinement configurations envisioned toconfine the energetic fusion plasma ionized particles. Itconsisted of two high-strength solenoidal coils placedsome distance apart. Theoretically, the charged particleswould remain in the lower field strength region betweenthe two magnets and be reflected by the higher fieldregions close to the coils. In experiments, there was anunacceptable amount of plasma “leaking” through thecoils. Other coil and field variations were examined tohelp control the leakage, some by combining a stringof solenoidal coils with higher strength yin-yang coilsat the ends (tandem mirror). Another arrangement was

NUCLEAR FUSION: GLOSSARY AND ACRONYMS xxi

arranging the solenoidal coils in a toroid shape call theElmo Bumpy Torus.

Magnetically confined fusion energy (MFE) A hotionized plasma is confined magnetically with sufficientpressure, temperature, and time to fuse light elements toother elements with a slightly decreased total mass thatyields a net energy release. Small and moderate-sizedexperiments use normally conducting magnets for theplasma confinement. Larger experiments and eventualpower plants have or will incorporate superconductingmagnets. Many magnetic configurations exist to confinethe plasma, the tokamak being the most studied anddemonstrated. Containment can be either pulsed orpreferably steady-state.

Neutronics, Nucleonics This branch of physical scienceestimates the lifetime of first wall and blanket structuresdue to neutron damage, the effectiveness of the blanketto breed tritium, the radiation damage to the supercon-ducting materials and insulators, the effectiveness of theshields to protect the externals, and the activation of thepower core components.

Nominal dollars Nominal dollar cost is the cost of anitem measured in as-spent dollars and includes inflationeffects. Nominal dollars are sometimes referred to as“current” dollars, “year of expenditure” dollars, or “asspent” dollars. With this analysis metric, a value forinflation must be assumed for the period of construction.

Nuclear fusion The fusing of light atomic nuclei intoheavier elements (higher atomic number) with a slightlyreduced combined mass that releases a considerableenergy (usually in the form of energetic neutrons,alpha particles or radiation) that can heat componentssurrounding the plasma to produce electricity.

Poloidal field magnets (coils) Poloidal field (PF) mag-nets are coils that generate magnetic fields in the poloidaldirection (around the torus in the short direction) of thedevice. In the tokamak designs, the coils are a set of10–20 circular coils that either inductively initiate theplasma current or shape the plasma. Induction coils arelocated in near the center of the machine inward ofthe TF coils. In tokamaks, the shaping coils are locatedabove, below, and radially outward of the TF coils.

Radioactive decay The transformation of one radioiso-tope into one or more different isotopes (known asdecay products or daughter products), accompanied by adecrease in radioactivity (compared to the parent mate-rial). This transformation takes place over a well-definedperiod of time (half-life), as a result of electron capture;fission; or the emission of alpha particles, beta particles,or photons (gamma radiation or x-rays) from the nucleusof an unstable atom. Each radioisotope in the sequence(known as a decay chain) decays to the next until itforms a stable, less energetic end product. In addition,

radioactive decay may refer to gamma-ray and conver-sion electron emission, which only reduces the excitationenergy of the nucleus.

Scrape-off layer (SOL) The distance between the outerplasma boundary and the first wall is called thescrape-off layer. This is usually on the order of 5–10centimeters.

Shield The shield is located immediately radially outwardfrom the plasma and behind the blanket and divertor.The shield subsystem function is to capture most of thehigh-energy neutrons escaping the first wall, blanket, anddivertor subsystems and streaming through penetrationsand assembly gaps. The requirement for the shield is toprovide adequate radiation protection for all the furtheroutboard components (e.g., coils) as well as workers, thepublic, and the environment. The superconducting coilsare quite susceptible to radiation damage, so these arecritical components to be shielded. Approximately 10%of the total neutron energy is captured by the shield. Thisamount of energy is significant, so the current designapproach is to employ to layers of shielding if needed.The innermost layer operates at the same temperatureof the blanket and contributes to the electrical energyproduction. A second layer receives much less neutronflux and it cooled with low temperature water.

Solid breeder blanket The solid breeding blanketsemploy solid pellets or pebbles of lithium ceramic com-pounds, typically with helium flowing in cooling chan-nels to remove the thermal energy.

Stellarator (configuration) Proposed in 1950 by Spitzer,the stellarator magnetic fusion confinement approachis similar to a tokamak in that it has both toroidaland poloidal magnets to contain and shape the plasma.In stellarators, the stabilizing toroidal plasma currentis generated by shaping the toroidal coils to inducethe plasma current. Stellarators differ from tokamaksbecause they are not azimuthally symmetric and lessprone than tokamaks to plasma instabilities and dis-ruptions. The first stellarators wound the toroidal coilsin a continuous helix to induce the toroidal current.This was appropriate for experiments, but would notbe practical for larger experiments or power plants. Animproved approach utilized sets of differing individualmodular coils that were highly shaped to accomplish theplasma current generation and form a repeating geomet-rical plasma shape called a period. Stellarators can bedesigned from two periods up to many periods. Stellara-tors also need divertors to capture and remove chargedparticles, ions, and electrons that escape the magneticfield lines. The complex stellarator TF coil geometriescomplicate the maintenance approach and suggest smallreplacement assemblies.

xxii NUCLEAR FUSION: GLOSSARY AND ACRONYMS

Tokamak (configuration) The tokamak is a magneticfusion confinement approach in the shape of a toroid(donut) configuration that was originally developedby the Russians in the 1950s. This configuration haselliptical D-shaped plasma cross-section formed withequally spaced planar toroidal field (TF) coils to confinethe plasma. Additional poloidal field (PF) coils, externalto the TF coils, further shape the plasma. Sets ofdivertor, equilibrium field, and central solenoid coilsare necessary to further shape and position the plasmawithin the toroidal vessel. The solenoidal coils inducea transformer action in the plasma to initiate a toroidalplasma current (10 s of MA). This toroidal currentflowing through the plasma is a defining feature forthe tokamak that generates a helical component ofthe magnetic field for plasma stability. Early tokamakexperiments created and sustained (for a brief time)the toroidal plasma current with transformer inductanceusing the solenoidal coils, but pulsed operation is notsuitable for power plants. Tokamaks are capable ofreaching steady-state operating conditions using currentdrive systems of radio frequency or neutral beam sub-systems. The plasmas of tokamaks (and other magneticconfigurations) may suffer instabilities that lead todisruption or edge-localized modes where the plasmabulges out and contacts the walls, thus damaging it. Alltokamaks employ divertors in either single or double-null configurations to collect the charged particles, ions,and electrons that escape the magnetic field lines.

Toroidal field (TF) magnets (coils) Toroidal field (TF)magnets are coils that generate magnetic fields in thetoroidal direction (around the torus in the long direction)of the device. In the tokamak designs, the coils area D- or modified D-shape that are planar. There areusually from 12 to 18 identical coils, equally spaced.The tokamak TF coils do not generate a plasma currentin the toroidal direction, but rely on the PF coils toinitiate the plasma current. The maintenance approachmay be a factor that helps define the specific shape. Inthe stellarator design, the TF coils are highly shaped bothnon-planar and radially in order to generate a plasmatoroidal current as well as the toroidal magnetic field.Early stellarator TF designs were continuously woundcoils around the toroid, but later TF coils were desiredto be modular for ease of fabrication and maintenance.Other toroid devices use TF coils, combining some ofthese features.

Vacuum vessel A continued fusion reaction cannot besustained in the presence of impurities, even if the pres-sure, temperature, and time conditions are met. Anyminor amount of impurities (gases or particulates) wouldimmediately cease the fusion reaction, which is a goodsafety feature. However, fusion requires an extremelyhigh vacuum with a very clean environment inside the

plasma chamber. The typical vacuum chamber design isa D-shaped toroid that completely encloses the plasma,the fusion energy capture and conversion subsystems(first wall, blanket, divertor and shield), internal struc-ture, and heating and current drive launchers/ducts. Intokamaks, the coil subsystems are typically external tothe vacuum vessel. Small and large ports are necessaryto accomplish maintenance, heating/current drive, instru-mentation, and vacuum pumping. A small amount ofnuclear energy will escape the internal shielding thatwill heat the vacuum vessel requiring a low temperatureheat removal, typically by water.

ACRONYMS

Abbreviation Expansion

ITER ITER is an international collaboration tobuild a fusion experimental reactor thatproduces, for a short period, more energythan it consumes. This reactor extendsthe fusion experimental database to helpenable fusion to be a power-producingenergy source. The acronym originallymeant International ThermonuclearExperimental Reactor, but currently it isusing ITER as its name. It is currentlybeing constructed and is expected toproduce the first DT plasma in 2026 andoperate for a few decades. It is expectedto exceed ignition conditions andproduce 500 MW of fusion power withan input of 50 MW for 400 seconds.

NIF National Ignition Facility, a U.S.laser-driven test facility,https://lasers.llnl.gov/

TF Toroidal FieldPF Poloidal FieldSOL ScrapeOff LayerRAFS Reduced Activation Ferritic SteelODS Oxide Dispersion StrengthenedSiC/SiC Silicon-Carbide CompositesLiPb A lithium lead eutectic is being proposed

for use in future fusion power cores asliquid metal tritium breeder and heattransfer media for blankets, shields, andheat transfer loops.The eutectic wasoriginally identified as 17 atom percentlithium and 83 atom percent lead. Morerecently the lower temperature LiPbeutectic point has been redefined to be15.7 atom percent lithium and 84.3 atompercent lead. The melting point of the

NUCLEAR FUSION: GLOSSARY AND ACRONYMS xxiii

LiPb eutectic is 235◦C, however theheat transfer loop will typicallyoperate between about 350◦C and700◦C, well away from the eutectictemperature.

ELM, ELMs Edge-Localized Modes are due toinstabilities in plasma confinementthat release bursts of energy andparticles impacting the first wall.

TBR Tritium Breeding Ratio. The metric forthe plant self-sufficiency to breed alltritium required for plant operationconsidering burn-up, losses,entrapment, and data uncertainties

NbTi Niobium-TitaniumNb3Sn Niobium-TinNb3Al Niobium-AluminumHTS High Temperature SuperconductorsBSCCO Bismuth Strontium Calcium Copper

Oxide

YBCO Yttrium Barium Copper OxideEC Electron CyclotronIC Ion CyclotronH-NB Heating-Neutral BeamLH Lower HybridQ Ratio of output power to input powerWBS Work Breakdown StructureCBS Cost Breakdown StructureCOE Cost of ElectricityBOP Balance of PlantIDC Interest During ConstructionEDC Escalation During ConstructionAFUDC Allowance for Funds Used During

ConstructionEMWG Economic Modeling Working GroupFCR Fixed Charge RateRF Radio FrequencySCR Scheduled Component ReplacementD&D Decontamination and Decommissioning

PART I

GENERAL CONCEPTS

1NUCLEAR ENERGY: PAST, PRESENT, AND FUTURE

Jay LehrThe Heartland Institute, Chicago, IL, USA

Unlike some aspects of nuclear technology, the processof generating electricity in a nuclear power plant is notvery complicated. U235, a naturally occurring element, isone of the few materials on Earth that can be forced toundergo fission—its atoms can be forced to split, releasingprodigious amounts of energy. In a nuclear power plant,uranium pellets arranged in rods are collected into bundlesand submerged in water. Induced fission heats the waterand turns it into steam, which drives a steam turbine, whichspins a generator to produce power.

According to Marshall Brain, whose essay “HowNuclear Power Works” appears on the HowStuffWorks Website (http://science.howstuffworks.com/nuclear-power.htm),“a pound of highly enriched uranium . . . is equal tosomething on the order of a million gallons of gasoline.When you consider that a pound of uranium is smallerthan a baseball, and a million gallons of gasoline wouldfill a cube 50 feet per side (50 feet is as tall as a five-story building), you can get an idea of the amount ofenergy available in just a little bit of U235.” One metricton of nuclear fuel produces the energy equivalent of twoto three million tons of fossil fuel. Due to the abundanceof radioactive minerals in the Earth’s crust, nuclear poweroffers what some believe to be a limitless supply ofreasonably priced energy, as long as we safely contain theradioactive material.

Reprinted from ENERGY & ENVIRONMENT, VOLUME 21 No. 2(2010), MULTI-SCIENCE PUBLISHING CO. LTD., 5 Wates Way,Brentwood, Essex CM15 9TB, United Kingdom

Nuclear Energy Encyclopedia: Science, Technology, and Applications, First Edition (Wiley Series On Energy).Edited by Steven B. Krivit, Jay H. Lehr, and Thomas B. Kingery. 2011 John Wiley & Sons, Inc. Published 2011 by John Wiley & Sons, Inc.

1.1 HISTORY

The first experimental nuclear power apparatus was createdin 1942 by Enrico Fermi and his graduate students atthe University of Chicago. A product of naval propulsionresearch, nuclear power emerged in the United States asa commercial power option in the 1950s. A Pennsylvaniautility, Duquesne Light, built the first commercial nuclearpower reactor at Shippingport, Pennsylvania, in 1954.Nuclear power was commercially attractive because itoffered the opportunity to generate power without the airpollution that accompanied the burning of fossil fuels.Waste volumes are comparably scaled: Fossil fuel systemsgenerate hundreds of thousands of metric tons of gaseous,particulate, and solid wastes. By contrast, according tothe Nuclear Energy Institute (NEI), boiling water nuclearpower reactors produce between 50 and 150 metric tons oflow-level waste per year, while pressurized water reactorsproduce between 20 and 75 metric tons. The volume andmass of the waste can be further reduced by 95% byreprocessing the spent rods.

At present, 33 countries around the world host 444 oper-ating commercial nuclear energy-fueled electric generatingfacilities. Those facilities have cumulatively recorded over10,000 years of operation. The United States remains thelargest single producer of nuclear energy in the world, with104 plants that supply over 800 billion kilowatt (kW) hours.In 1998, those plants supplied 674 billion kilowatt (kW)hours.

The gains came as a result of improving equipment,procedures, and general efficiency—not a single new

3

4 NUCLEAR ENERGY: PAST, PRESENT, AND FUTURE

nuclear plant was built over that period. The increasedefficiency and capacity of the nuclear fleet means theindustry added the equivalent of 26 new 1,000 MW reactorsto the grid. France has the second largest number of nuclearpower plants with 59, and three are under construction.Japan now has 55 nuclear power plants, followed by 35in the United Kingdom. Russia follows with 29, and thenGermany with 20. China currently has seven operationalplants and 132 more planned by 2020. Approximately 80%of France’s electricity demand is met by nuclear energy,while Britain uses nuclear energy to generate 23% of itselectricity. Other countries with significant nuclear powerinclude: Spain, 29%; Germany and Finland, 32%; Sweden,44%; and Belgium, 58%.

1.1.1 Accidents

The first recorded commercial nuclear power plant accidentoccurred in the United Kingdom at the Windscale powerplant on October 10, 1957 when fire destroyed the core of aplutonium producing reactor sending clouds of radioactivityinto the atmosphere, while the chemical accident couldhave caused fatalities, none were ever reported. The 1979event at Three Mile Island in the United States occurredbecause faulty instrumentation gave false readings for thereactor environment. That led to a series of equipmentfailures and human error. As a result, the reactor core wascompromised and underwent a partial melt. Radioactivewater was released from the core and safely confined withinthe containment building structure. Very little radiation wasreleased into the environment, and no health impacts wererecorded.

The Three Mile Island incident underscores the relativesafety of nuclear power plants. The facility’s safety devicesworked as designed, preventing injury to humans, animals,or the environment. The accident resulted in improvedprocedures, instrumentation, and safety systems, meaningnuclear reactor power plants in the United States today aresubstantially safer than they were in the past. Three MileIsland’s Unit One continues to operate with an impeccablerecord.

The worst nuclear power plant disaster in historyoccurred when the Chernobyl reactor in the Ukraineexperienced a heat (not nuclear) explosion. If such anexplosion were to have occurred in a Western nuclear powerplant, the explosion would have been safely contained.All Western plants are required to have a containmentbuilding: a solid structure of steel-reinforced concrete thatencapsulates the nuclear reactor vessel. The Chernobylplant did not have this fundamental safety structure.The explosion blew the top off of the reactor building,spewing radiation and reactor core pieces into the air.The graphite reactor burned ferociously—which would nothave happened if the facility had a containment building

from which oxygen could be excluded. The design of theChernobyl plant was inferior in other ways as well.

Unlike the Chernobyl reactor, Western power plantnuclear reactors are designed to have negative powercoefficients of reactivity that make such runaway accidentsimpossible: When control of the reaction is lost, the reactionslows down rather than speeds up. The flawed Chernobylnuclear power plant would never have been licensed tooperate in the United States or any other Western country.The accident that occurred at Chernobyl could not occurelsewhere. The circumstances surrounding the Chernobylaccident were in many ways the worst possible, with anexposed reactor core and an open building. Thirty-one plantworkers and firemen died directly from radiation exposureas a result of the Chernobyl accident.

1.2 RADIATION

In September 2000, the United Nations ScientificCommittee on the Effects of Atomic Radiation(UNSCEAR) published its Report to the General Assemblywith Scientific Annexes, a document of some 1,220 pagesin two volumes. According to the UNSCEAR report andsubsequent discussions, roughly 1,800 thyroid cancer casesin children and some adults might reasonably be attributedto radiation exposure after the Chernobyl incident. Morethan 99% of those cancers were cured. Beyond the thyroidcancers, reported UNSCEAR, there is no evidence ofany major public health impact attributable to radiationexposure after the Chernobyl accident.

In countries that do not reprocess their spent nuclear fuel,of which the United States is the primary one, the nuclearwaste disposal is a political problem because of widespreadfears disproportionate to the risk reality. Waste disposal isnot an engineering problem because the United Kingdomand most other countries manage their small volume withrelative ease. But in the United States, spent nuclear fueland high-level radioactive waste have been accumulatingfor nearly 60 years, when nuclear materials were first usedto produce electricity and to develop nuclear weapons.

Nuclear fuel has been used in 104 nuclear power plantsin the United States and nearly 200 of that nation’s nuclearnaval vessels. As in the United Kingdom, the fuel is solid,in the form of ceramic/uranium pellets the size of a pencileraser. After a few years in a reactor, the uranium pelletsin the fuel assembly are no longer efficient for producingelectricity. At this point the used, or “spent,” fuel assemblyis removed from the reactor and placed in a pool of waterto cool.

1.3 WASTE AND REPROCESSING

In most other countries where nuclear power is generated,these fuel rods are chemically reprocessed for additional