nuclear power - stormsmith.nl · i14 Nuclear safety Military and civil nuclear technology are ......

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nuclear power

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Nuclear power insightsby

J.W. Storm van Leeuwen

Independent consultant

Ceedata Consultancy

July 2012

[email protected]

Nuclear power is an emotionally charged issue. Heated discussions indicate widely different viewpoints and widely different levels of knowledge. Due to the exceedingly complexity of the issues related to nuclear power, misunderstandings and fallacies may easily trouble the discussion.

This website aims at supplying insights in a number of issues from a scientific point of view. A number of opinions and claims on the matter of nuclear power are tested against common scientific wisdom and basic physical laws. Financial and economic issues are not or indirectly addressed.These insights are presented as separate brief self-supporting texts, intended to keep the content accessible to policy makers and a broad public not well introduced into nuclear matters. Each text can be read independently of the other and in arbitrary order, and contains links to other insight items. In a number cases this set-up may result in some overlap of different texts. Many of the insight texts have diagrams with captions added from the original publications, giving more detailed information. This additional information can be read independently from the main text of an insight item.

To keep the items short and easily readable, jargon is avoided as much as possible and references to original sources are omitted. These references can be found in the original reports the brief texts are based on: Nuclearpower,theenergybalance, February 2008, Healthrisksofnuclearpower, November 2010, Nuclearpower,energysecurityandCO2emission, May 2012, the full reports of which are available as pdf files [downloads] on this website. These reports are the results of a comprehensive study and intensive correspondence with numerous experts all over the world during the past years [about study].

Comments are welcome. The author encourages a discussion on scientific arguments.

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Contents

CommunicationHowisthecommunicationbetweenthenuclearindustryatonehandandthepoliticiansandpublicattheotherhand?How open, how sincere and how comprehensive is the information flow from the nuclearindustrytopolicymakersandthepublic?Towhichdegreeisthisatwo-waycommunication?

i01 Communication nuclear industry – public Complexity and opacity One-sided information and conflict of interests Uncertainties and unknowns Downplaying the hazards Fostering the myths One-way communication

i02 Economic vs physical perspective Time horizon Global issues Physical energy analysis System boundaries

i03 How controllable is nuclear power?

Why nuclear?Whicharetheargumentsofthenuclearindustrybackingtheassertionthatnuclearpowerissafeandindispensableforclimatecontrolandenergysecurity?Howvalidarethesearguments?

i04 Why nuclear power? Claims of the nuclear industry Clean Cheap Safe Secure Indispensable Sustainable Bright outlook

i05 Climate change Nuclear share Present nuclear CO2 emission CO2 trap of nuclear power Greenhouse gases other than CO2 Coal equivalence

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i06 Energy security What means ‘energy security’? Fallacies Après nous le déluge

i07 How clean is nuclear power? Greenhouse gases Chemicals Radioactive discharges Ecosystem disturbances Depletion of valuable materials

Nuclear facts and featuresWhataretheunambiguousfactsanduniquefeatures,anydiscussionontheadoptionofnuclearpowershouldbebasedon?

i08 Unique features of nuclear power Man-made radioactivity Mobilisation of radioactivity Metal as energy source Time frame Complexity Irreversible consequences

i09 Radioactivity Isotopes Radioactive decay Ionizing radiation Half-life Nuclear bomb equivalents

i10 Radioactive materials Spent nuclear fuel Fission products Actinides and minor actinides Activation products

i11 Radioactive waste streams Mining waste Operational waste Routine releases Spent nuclear fuel Decommissioning and dismantling waste Isolation from the human environment Geologic repository Mine rehabilitation

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Technical analysisWhichindustrialprocessesandactivitiesarerequiredtomakenuclearenergyavailabletotheconsumer?Howdoesthenuclearenergysystemtechnicallywork,inbroadoutlines?Howmuchmaterialsandenergyareconsumedperunitusefulenergydeliveredbynuclearpower?

i12 Life cycle analysis of the nuclear energy system Nuclear process chain Cradle to grave Energy balance of the nuclear system Full-load years and energy payback time Energy return of energy investment EROEI Methodology of energy analysis

i13 Materials and nuclear power from cradle to grave Comparison Specifications of the reference nuclear power system Materials balance of nuclear power from cradle to grave Specifications of the reference Wind power system

SafetyWhatdoesthenuclearindustrymeanwithsafenuclearpower?Inwhatrespectsisnuclearpowerasafewayofenergygeneration?Onwhatempiricalandscientificevidencebasesthenuclearindustryitsopinion?

i14 Nuclear safety Military and civil nuclear technology are inseparable Proliferation Nuclear terrorism and MOX fuel Reactor safety studies Spent nuclear fuel pools Nuclear safety is not set by safety studies, but by practice Main safety concern: dispersion of radioactivity

i15 Engineered safety Quality requirements Bathtub hazard function Bathtub curve and nuclear technology Preventable accidents

i16 Energy debt Energy on credit Paradigm barrier Economic challenge A dangerous misconception Energy is the limiting factor

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Health risksWhatarethespecifichealthrisksofnuclearpower?Arenuclearhealtheffectscurableoraretheyapassingthing?Arenuclearhealthrisksavoidable?Whichroleareeconomicappraisalsplayinginrelationwithnuclearhealthrisks?

i17 Dispersion of radioactivity Pathways Routine releases Unauthorized releases Uranium mining Depleted uranium Illegal trade and criminality Transport Cleanup, decommissioning and dismantling of nuclear plants Terrorism Armed conflicts Severe accidents

i18 Uranium mining Radioactive decay products Mill tailings Mine reclamation

i19 Routine releases of radioactivity Significance Discharges from reactors Interim storage of spent fuel Reprocessing plants

i20 Cleanup, decommissioning and dismantling Radioactive structures after closedown Nuclear power plants Reprocessing plants Health risks Radioactive debris and scrap Regulations and economics

i21 Severe accidents Meltdown Spent fuel pools Consequences Contamination

i22 Health effects of radioactivity in the human body Stochastic and non-stochastic effects Targeted, non-targeted and delayed effects Biomedical aspects of radioactivity Radiation-induced diseases

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i23 Downplaying the hazards Long time lag Downplay Evidence Health risks resulting from downplaying

i24 Limited knowledge on radioactivity Not all radioactivity is measured Troublesome detection of radioactivity Biomedical unknowns

i25 Health risks of nuclear power Reliance on models Pathways of radioactive discharges Risk enhancing factors Long time lag Cumulation effects Health risks of nuclear power and economics

i26 Economics and nuclear safety Economic vs physical perspective Liability policy Responsibilities De-regulation Relaxation of activity standards Relaxation of exposure standards Relaxation of safety standards Quality control and dependency of inspections

i27 Nuclear waste diluting Fallacy Increasing helth risks Low-level waste Military practice Civil practice Decommissioning and dismantling waste

OutlookWhatdoesthenuclearindustrymeanwith‘nuclearrenaissance‘?Whicharetheadvancedtechnicalconceptstheexpectationsofanuclearrenaissancebasedon?Isthematerializationofthenuclearrenaissanceamatterofpoliticsandcommunicationwiththegeneralpublic,amatterofeconomics,oraretechnicalissuesatstake?Whichtechnicaldevelopmentsmightbepivotal?

i28 Nuclear renaissance World nuclear capacity Adoption curve How likely is a nuclear renaissance?

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i29 Adoption of innovative technology History of nuclear power Maturity and obselescence of nuclear power

i30 Advanced nuclear concepts Advanced reactors and concepts of waste reduction Aerospace Plane Advanced uranium recovery

i31 Reprocessing Outline Discharges into the environment Practice Costs Historic purpose

i32 Recycling of plutonium and uranium (MOX) in LWRs Plutonium energy balance Terrorism threat Uranium View of the nuclear industry

i33 Breeder reactors Once-through mode Uranium-plutonium breeder concept Breeder cycle New names, no new concepts

i34 Partitioning and transmutation Radioactivity of spent nuclear fuel Concept Transmutation Minor actinides Partitioning Outline Feasibility

i35 Thorium as nuclear fuel Thorium cycle Uranium-233 Time frame Hybrid reactor Feasibility

i36 Nuclear waste reduction by reprocessing Nuclear waste per kilowatt-hour Volume reduction concept Misconception Flaws Fallacy Least hazardous treatment

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Summary Historic motive for reprocessing

i37 Nuclear fusion Hydrogen isotopes Fusion principle Controlled fusion: a moving target Challenges Tritium supply Materials Radioactive waste Energy balance

UraniumDotheuraniumresourcessetalimittotheexpansionofnuclearpower?

i38 Uranium supply Uranium occurrences Industrial view on resources Thermodynamic quality of uranium resources Depletion of uranium resources Energy cliff Energy cliff over time New discoveries of uranium resources Unconventional uranium resources Mineralogical barrier Uranium from seawater

FundamentalsWhichfundamentalphenomenaandscientificlawsareimportanttoknowwithrespecttothedeploymentofnuclearpower?Which consequences has one of themost fundamental laws of nature, the Second Law ofthermodynamics,forthesustainabilityofnuclearpower?

i39 Energy and thermodynamics Thermodynamics Energy First Law Spontaneous changes Entropy Second Law Potential energy Useful energy

i40 Entropy System and system boundaries Definition of entropy Entropy changes Observable anthropogenic entropy effects in the biosphere

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Ordered materials, functionality and entropy Fallacy of economic growth

i41 Consequences of the Second Law Validity of the Second Law Visibility of the consequences on global scale Principle of the Second Law Probability and the Second Law Heat engines Separation processes Coupled systems Ordered materials: reliability and energy investments Mineral energy sources are not sustainable Declining thermodynamic quality of mineral resources Photosynthesis in the biosphere, spontaneous order from chaos?

i42 Limitations of separation processes Separation processes Purification Extraction of uranium Enrichment of uranium Reprocessing

i43 Nuclear power and the Second Law Chemical pollution Radioactive pollution Thermodynamic quality of uranium ores Separation processes Inherently safe nuclear power is inherently impossible Latent entropy Materials specifications Advanced nuclear concepts Nuclear power cannot be not sustainable

i44 Zero-entropy energy, ZEE Physical sustainability criteria Constant flow and constant quality No contribution to the entropy of the biosphere Potential capacity

i45 Reliance on models Uncertainties in dose estimates Uncertainties in risk estimates Troublesome detection of radionuclides Inherently limited significance of models Why not start from empirical evidence?

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Concluding remarks and questionsWhatmightbetheconclusionofacomprehensivephysicalassessmentofnuclearpower?Whichfallaciesaretroublingtheformingofpublicopinion?

i46 How indispensable is nuclear power? Promoted image Cheap Climate change Clean and safe Energy security Sustainable energy Zero-entropy energy, ZEE Nuclear power is a dead-end road

i47 Is nuclear power obsolete?

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milling

mining

uranium ore

depleteduranium

conversion

reconversion

emissions

emissions

emissions

exploration

exploration

exploration

constructionof repository

constructionof repository

enrichment

fuel elementfabrication

milltailings

green fields

waste

overburden+ waste

waste

waste

electricity

interim storage

nuclearpower plant

finalsequestration

finalsequestration

Nuclear process chainLWR once-through

waste

geologicrepository

geologicrepository

spent fuel

spent fuelpackaging

wastepackaging

wastepackaging

wastepackaging

front end

back end mining areareclamationdecommissioning

& dismantling

construction

operation &maintenance



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The nuclear systemOutline of the full nuclear process chain: the industrial processes required to unlock the nuclear energy

in uranium and convert it into electricity. These industrial activities are grouped in three sections: front

end, mid-section and back end. The front end processes are needed to extract uranium from the earth’s

crust en convert it into nuclear fuel. The mid section comprises construction of the nuclear power plant,

plus operating, maintenance and refurbishments of the power plant during its operational lifetime. Both

front end and mid-section comprise mature processes. The back end comprises all processes required to

handle the radioactive waste as safe as possible and to store it isolated from the human environment.

The processes presented in the yellow boxes with dotted lines are not operational and exist only on paper.

The grey arrows represent material flows that should have been established, but still do not exist.

LWR = light-water reactor. At present more than 88% of world power reactors are LWRs; all nuclear power

stations planned and under construction are LWRs. Once-through means without recycling of uranium and

plutonium.

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making things transparentnuclear power insights

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Communication nuclear industry – public

What lies behind this glossy image?

Complexity and opacity

The nuclear energy system is the most complex energy system ever, not only in the technical sense, but also in economic, political and societal senses. As a result the nuclear complex is opaque to the public and most policy makers. The confusing situation is exacerbated by divergent perceptions of the large uncertainties still existing with regard to the inevitable consequences of nuclear power. Economic, political and/or scientific arguments may easily exhibit widely different scopes and turn out to be not always compatible.

Reliable insight in nuclear matters is further complicated by the misleading practice of the nuclear industry to present unproved technical concepts as being mature technology, waiting on the shelf to be implemented on demand.

One-sided information and conflict of interests

Another factor troubling the transparency of the nuclear world is the one-sidedness of the information flow to people outside of the nuclear world. The primary information on nuclear power to the public and decision makers originates almost exclusively from institutes with vested interests in nuclear power, such as: International Atomic Energy Agency (IAEA), Nuclear Energy Agency (NEA), Nuclear Energy Institute (NEI), World Nuclear Association (WNA), Areva, Electricité de France (EdF), the latter two being 90% state-owned.

The World Health Organization (WHO) cannot operate independently of the IAEA on nuclear

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matters, according to a UN resolution of 28 May 1959. There are strong connections between the IAEA and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and the International Commission on Radiological Protection (ICRP), the authority who formulates the standards of allowable radiation doses.How independent is the IAEA, who’s mission statement reads promotion of the use of nuclear energy and the achievement of ‘high levels of safety’?

How free are universities in their choices of subjects for research and publications, if a significant part of their costs are paid for by the nuclear or nuclear-related industry?

Uncertainties and unknowns

No empirical figures are available of the energy and material consumption of the full back end of the nuclear energy system, for a number of essential processes still don’t exist [more i12]. In addition even emprical figures often exhibit considerable spreads in their values. Any statement with solid figures, without indicating an appreciable uncertainty range, is unscientific and misleading. Assessment of the implications of nuclear power should taking the whole cradle-to-grave period into account, because the greatest safety and health risks originate in the activities and processes following the final shutdown of a nuclear power plant, the so-called back end part of the nuclear process chain. Precisely these processes pose the greatest uncertainties and unknowns related to safety and health risks.

Downplaying the hazards

Usually it is hardly possible to prove unambiguously the relationship between a once contracted dose of radiation with an indiviual and carcinogenic, mutagenic and teratogenic effects he/she develops later, because of the long incubation periods, months to years or decades. The long time lag between exposure and observable health effects – for example the heritable damage to egg cells in young women may only become evident after some 30 years – forces the medical sciences to employ special methods to assess the hazards of nuclear power. What is known about the effects of chronic exposure to low levels of radioactivity in drinking water and food?

The long time delay gives the nuclear industry the opportunity to downplay the effects and even to deny radioactivity being the cause of observed adverse health effects [more i22]. Other factors are blamed to be the cause of observed disorders, sometimes even psychosomatic factors: ‘radiophobia’, the fear of radiation. Of course this kind of assertions come from people living far from radioactive-contaminated areas.

From a purely scientific point of view above assertions are fundamentally flawed. When it is not possible to unambiguously prove that radioactivity is the cause of adverse health effects observed with a individual, then you have to prove that radioactivity cannot be the cause, before asserting that radioactivity is not the cause but other factors are.

At present the nuclear industry is strongly downplaying the gravity of the Fukushima disaster, which is called ‘non-catastrophic’, or even having ‘no ill effects’ [more i23]. The worst effects in the industrial view are economic: delay for new nuclear power stations.

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Fostering the myths

During the past two decades, little spectacular developments have been visible with the nuclear industry, other than upgrades of existing reactor concepts (PWR and BWR) to a higher power level and a claimed, but yet to be proved, higher grade of safety. The world operating nuclear capacity has been nearly constant since the early 1990s and is will decline during the next decades [more i28, i29]. In addition there was the silent failure of the fast breeder development, disguised behind asserted economic, political and societal resistances [more i33].

Understandably the nuclear industry is looking for innovations, to keep nuclear power in the picture and to create new markets. Carefully an image of advanced and highly promising technology is being maintained. Old reactor concepts – such as molten-salt fast reactors, high-temperature gas-cooled reactors, accelerator-driven sub-critical reactors, traveling-wave reactors, liquid-metal cooled fast reactors, thorium-fuelled reactors, actinide burners – are brushed up and presented under new names, for example in the Generation-IV Roadmap. These novel-looking concepts would promise to be inherently safe, to burn fissile material much more efficiently and to generate much less long-lived radioactive waste than currently operational reactors. However, can they fulfil those promises?

Examination of the advanced concepts reveals fundamental flaws, originating from a belief in unlimited possibilities of technology, not allowing for the limitations set by natural laws, especially the Second Law of thermodynamics, and the finite size of the biosphere [more i30, i43]. For that reason the advanced concepts could only function in cyberspace and are to be classified as myths.The feasibility of the claims cannot be judged on feasibility by the public and politicians. Only experts, well-introduced in nuclear technology, can discern proven technology from paper concepts, and empirical facts from wishful thinking.

The futuristic sounding ideas, the myths, are eagerly adopted by enthousiastic people who believe in the unlimited possibilities of technology. Evidently the nuclear industry is pleased with any publicity which stimulates public and political support and, more importantly, financial support. Futuristic technical concepts promising nearly unlimited energy resources, safe, secure, clean, cheap, have a great appeal to the public [more i04]. The nuclear industry is the last who would publicly question the feasibility of the myths, even if they have become deformed in the public domain. It might be important to know the source of a statement or report concerning such an advanced concept.

One-way communication

A few habits lead to the one-sidedness of the communication from the nuclear world to the general public, such as:• downplaying hazards,• disposing of objections and complaints from the public as if originating from a lack of

knowledge and/or from leftish environmental activism,• asserting unverifiable concepts,• not discerning between proved technology and theoretical concepts, existing only in

cyberspace.

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militaryissues

proliferation

politics

terrorism

energysecurity

safety

biosphere

financialinterests

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Figure 01-2. Stakeholders of the nuclear complex

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i02

Economic vs physical perspective

A fundamental issue in the discussion on nuclear energy is the scope of the arguments. Does one take the entire nuclear process chain into account, or only one partial process of it, usually the nuclear power plant itself?Does one use economic arguments, or physical arguments, or does one mix up economic and physical arguments without explicitely defining his scope?Which timescale has one in mind, when discussing nuclear energy? A few years until the next elections, a few decades according to an authoritative scenario of the nuclear industry, or the whole cradle-to-grave periods of the involved nuclear power stations, which are relevant for the whole society?

Time horizon

The nuclear process chain encompass a substantial number of partial processes, which are run by different companies at widely dispersed places (may be on different continents) and often at different points in time. The time lag between processes directly related to one particular nuclear power station may vary from a few years to more than a century.Economic calculations are done per company, and consequently per partial process of the nuclear chain, and have a short time horizon, usually no more than a couple of years. This way of thinking does not result in a reliable overview of the whole chain.

Global issues

Climate control by mitigation of CO2 emissions and energy security are global issues, for that reason the complete chain of industrial activities needed to make nuclear energy available should be taken into account, over the full cradle-to-grave period [more i12].

Physical energy analysis

Answers to question regarding CO2 emissions, energy security and safety of nuclear power can only be found by means of a complete life-cycle assessment (LCA) and a physical energy analyis of the complete nuclear process chain [more i12].Energy is a conserved quantity, energy units do not depend on place and time, nor on politics, nor on economic concepts. Essential is that all energy flows involved in nuclear power are analysed and accounted for in the material and energy balance.

System boundaries

Arguments based on the free-market paradigm are not well-suited to assess the environmental and societal implications of nuclear power in a global perspective with a long time horizon.Only a method based on unambiguously defined quantities which do not depend on place, time and cultural factors is appropiate.

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How controllable is nuclear power?

Controllability of nuclear power is a broad notion with many different aspects. The nuclear energy system is not just a matter of technology: it has also military, political, economic, societal and safety aspects.The unique properties of the nuclear energy system, such as the generation of tremendous amounts of man-made radioactivity and the unprecedentedly long time frames (100-150 years) of causally connected sequence of events, hold a potential of uncontrollable developments.

How to deal with the many technical uncertainties and unknowns with regard to the completion of the nuclear process chain?

What are the causes why up until today the costs of construction of nuclear power plants still are badly controllable, after more than 50 years of civil nuclear power? Are the causes regulations, which are existing already for decades, or should one look for other causes, such as short-term financial interests, bad engineering, insufficient quality inspections?Why does nuclear power still need heavy financial state support, after 60 years development? What does the nuclear industry mean with ‘free market’?

How is possible that the nuclear industry strongly advocates the construction of new nuclear power plants, without any solution to safely complete the back end of the nuclear process chain, except reassuring assertions refering to concepts existing only in cyberspace?

Why did politicians accept the responsibility for the completion of the back end of the nuclear process chain, with costs as high as the construction and operation of nuclear power plants jointly, to be payed by the taxpayer? How democratic are the decision processes concerning nuclear power?

What measures does the nuclear industry propose to eliminate the routine releases of radioactivity by nuclear power plants which are proved to cause cancer and leukemia with young childern?

Are the nuclear industry and responsible decision makers aware of the vastness of the irreversibly affected land areas, hundreds of thousands of square kilometers, with dangerous radioactive contamination? Are they aware of the consequences of these contaminations for the populations living there and who are chronically exposed to the radioactivity, generation after generation? Does the nuclear industry think these consequences are worthwile and are in proportion to the nuclear share of less than 2% of the world energy supply?

How do the nuclear industry and responsible decision makers deal with irreversibility of the effects and consequences of radioactive contamination? Aprèsnousledéluge?

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Why nuclear power?

Claims of the nuclear industry

Nuclear power is being promoted by the nuclear industry based on a standard series of arguments, being used in various combinations, depending on the context of the promotion. According to these standard arguments nuclear power would be:• clean• cheap• safe • secure• indispensable • sustainableNuclear power would have a bright future, on the brink of a nuclear renaissance. New concepts would just be waiting on the shelf for large scale implementation, solving the energy supply problems for centuries to come. Obviously the nuclear industry has the right to promote its assets and to highlight favourable aspects. Just as much the taxpayer has the right to have a critical look at the advocated selling points of the nuclear industry and to get unbiased and complete answers to his questions.

How valid are the claims of the nuclear industry? Below the claims are briefly addressed.

Clean

What does the nuclear industry mean with ‘clean’? Climate neutral: no emission of CO2, no greenhouse gases at all? No chemical pollution? Are radioactive releases ‘clean’? A comprehensive life cycle analysis and energy analysis of the complete nuclear energy system from cradle to grave proves none of these claims to be valid. The nuclear reactor is the only part of the nuclear system that does not emit CO2, all other parts do. Emissions of greenhouse gases [ more i05] and chemical discharges [more i07, i13] into the environment are kept secret. Radioactive emissions are concealed, or played down as ‘harmless’ if disclosed nevertheless. Even emissions of radioactive materials classified as ‘weakly’ radiotoxic turn out to be harmful for people living in the neighbourhood of nuclear power stations. Not to speak of the massive radioactive contaminations after large accidents, such as Chernobyl and Fukushima [more i17, i21, i22, i43].

Cheap

Nuclear power is claimed to be cheap, but compared to which other energy sources? What costs are accounted for and which not? Which time horizon is valid for the calculations of the nuclear industry? The next elections, ten years or the cradle-to-grave period of a nuclear power plant?It turns out that the nuclear industry is omitting a considerable part of the costs associated with a given nuclear power station, namely the investments to be spent after final shutdown of the

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power station. Invariably these costs are passed on to the taxpayer in the future: the energy debt [more i16]. Nuclear power is energy on credit.

Safe

Nuclear safety is a complex isuue, involving many different aspects of nuclear power, such as proliferation, nuclear terrorism, reactor safety and dispersion of radioactivity in the human environment. The nuclear industry seems to base its assertion of safe nuclear power on a small number of theoretical studies of failure modes of a limited number of reactor types. According to these studies a reactor core meltdown would occur once in the several million reactor-years. With about 400 reactors worldwide this would mean one meltdown every several thousand years. During the last 40 years three major meltdowns occurred: Three Miles Island, Chernobyl and Fukushima: once in the 10-20 years. So what is the meaning of the theoretical safety studies? Moreover, these studies do not include other nuclear facilities containing even more radioactivity than a reactor.Safety concerns posed by the large and continuing releases of radioactivity by nominally operating reactors and other nuclear facilities (e.g. uranium mining) appear to be no issue with the nuclear industry.From the basic laws of nature follows that inherently safe nuclear power is inherently impossible [more i14, i15. i43].

Secure

Energy security is not a well-defined notion. From a political viewpoint independency on other nations for the energy supply and geopolitical stability are important issues. From a corporate viewpoint the prolongation of a given energy system, belonging to the core business of a given industry, may be the main issue.The view the nuclear industry with regard to energy security is based on two premises: • trouble-free implementation of unproven technology• availability of inexhaustable uranium resources.Both premises turn out to be fallacies, for reason of ignorance of fundamental natural laws [more i30 and i38].A third factor, implicite and unspoken, strongly contributes to the optimistic view of the nuclear industry: the systematic postponement of the back end activities to future generations: the energy debt [more i16, i43].

Indispensable

At present the nuclear share of the world energy supply is 1.9%, and declining. Even if nuclear power would be CO2 free, which it is not, then the reduction of the human CO2 emission could not be more than 1.9%. In the most optimistic scenarios of the so-called ‘nuclear renaissance’ the nuclear share would be no higher than 3-4% of the world energy supply by the year 2050. With improvement of the energy efficiency of economic activities energy reductions of 20-40% are possible without sacrificing comfort.From basic natural law follows that the use of uranium (and other fossil fuels), unavoidably results in an ever-growing environmental mess [more i39, i41, i43, i46].The sole solution of the energy and climate problematique lies at our feet: the utilisation of the full potential of energy conservation combined with the transition to renewables [more i44].

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Sustainable

The qualification ‘sustainable’ has different connotations: economic, physical, cultural. From a physical viewpoint a sustainable energy supply system should comply with three conditions:• lasting for indefinite periods of time,• without inflicting damage to the environment,• potential capacity meeting the world energy demand.From the basic laws of nature follows that such any sustainable energy supply is possible only if based on solar energy. No mineral energy source can be really sustainable. The joint capacity of renewable energy sources (e.g. wind, photovoltaics, concentrated solar power), though not infinite, is amply sufficient to meet the world energy demand [more i44].

Bright outlook

Nuclear power would have a bright outlook. This promotional viewpoint dates from the AtomsforPeaceprogram, launched by President Eisenhower in 1956.Today the nuclear industry states the position that a nuclear renaissance would ne imminent. Scrutiny of the arguments behind this position revealsExamining the development of civil nuclear power during the past 60 years, one has to conlude that nuclear power is an obsolete energy source [more i47].

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Climate change

Nuclear share

The potential contribution of nuclear power to the mitigation of the emission of greenhouse gases is and will remain negligible in the foreseeable future, for several reasons:• The current nuclear share of the world energy supply is less than 2%. This will decline to less

than 1% by 2050, if the world nuclear capacity would remain flat at the current level of 370 GWe, due to a steadily growing world energy consumption.

• At present the world nuclear capacity is declining at an increasing rate, so the nuclear share might end up near zero by 2050-2060.

• Even if the most ambitious nuclear constuction program would be realized, the nuclear share would remain flat at 2% or would slightly rise to 3% by 2050.

Reduction of the anthropogenic CO2 emission by tens of percents could be realized by improvements of the energy efficiency.

Present nuclear CO2 emission

Under the current conditions the specific CO2 emission of nuclear power is roughly 80-130 gram CO2/kWh. The nuclear reactor is the only technical component of the nuclear energy system that emits virtually no CO2. All other processes of the nuclear process chain, comprising construction of the nuclear power plant, the production of nuclear fuel from uranium ore, maintainance and operate the plants and to handle the radioactive waste streams, are conventional industrial processes emitting CO2 and other greenhouse gases [more i07, i13].

CO2 trap of nuclear power

The specific nuclear CO2 emission will rise during the next decades, due to the depletion of high-quality uranium resources and dependency on ever decreasing ore quality. Lower grade ores require more energy per unit recovered uranium and consequently cause higher CO2 emission [more i38]. If no new large high-quality resources will be discovered, the nuclear CO2 emission will eventually surpass that of fossil-generated electricity. This could happen within the lifetime of new nuclear build.

Greenhouse gases other than CO2

Few, if any, data have been published on the emission of greenhouse gases other than CO2 by the nuclear energy system. In view of the massive amounts of fluorine and chlorine and their compounds in the nuclear fuel processing, emissions of potent greenhouse gases seem not only possible, but likely. No chemical plant is leak-proof [more i07, i13, i43].

Nopublisheddatadoesnotequal‘noemission’.

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Coal equivalence

At a grade of 200 gram uranium per tonne rock as much ore has to be mined and processed as the amount of coal burned to generate the same amount of electricity. The leanest uranium ores exploited today are at or even below this grade.The coal equivalence occurs at about the same grade as the CO2trap and the energycliff [more i38]. Nuclear power relying on poor ores, at grades of less than 200 grams of uranium per tonne rock, emits as much CO2 per kilowatt-hour as coal-fired power.

nuclear

traditional biomass

other renewables

hydro

oil 32.9%

gas 23.3%

coal 29.0%

1.9%

2.4%

10.0%

0.5%

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Figure 05-1. World energy production in 2010. The share of nuclear power was 1.9% in 2010 and is declining

year2070 20902010 2030 2050

400

2CO emission

(g/kWh)

Storm©

gas-fired power plant

scenario 1constant nuclear

capacity 370 GWe

scenario 2constant nuclear share

2% world E

Figure 05-2. CO2 trap of nuclear power.Inevitably the nuclear CO2 emission per kilowatt-hour will rise with time, due to the depletion of the high-

grade uranium ores and the resulting dependence on ever lower-grade ores. The year at which the nuclear

CO2 emission will surpass that of fossil fuels depends on the development of the world nuclear capacity

and the discovery of new high-quality uranium ores.

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10100 1 0.1

grams of uranium per kg rock

equivalent mass of coal

mass of oreto be processed

per unitgeneratedelectricity

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Figure 05-3. Coal equivalence.The amount of uranium ore to be processed per unit electricity delivered to the grid increases exponentially

with falling ore grades. At a grade of some 200 grams uranium per kilogram rock, the amount of uranium

ore equals the amount of coal burned to generate the same amount of electricity: the coal equivalence.

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i06

Energy security

What means ‘energy security’?

Energy security is not a well-defined notion. In the discussions on the future energy supply different viewpoints may emerge. From a political viewpoint independency on other nations for the energy supply and geopolitical stability are important issues.From a corporate viewpoint the prolongation of a given energy system, belonging to the core business of a given industry, may be the main issue.

The nuclear industry emphasizes the reliable production of electricity by nuclear power plants, contrary to the fluctuating renewable energy systems (wind, solar). The nuclear advocates don’t tell that nuclear power plants have to operate in base load, they cannot operate load-following like fossil power plants, and require a heavy grid and a large running backup power capacity (gas-fuelled) to compensate for power loss due to unplanned outages. Moreover, when the supply of electricity from renewables exceeds the demand at a given moment, the renewables are switched off the grid (e.g. in the USA and UK), to keep the nuclear power plants running at nominal capacity.The nuclear advocates also don’t tell that renewables are for free, abundant and constant of quality and availability. The fluctuations are relatively easy to compensate for by a smart grid and many micro cogeneration power units, as is proved by experience in Germany and Denmark. Besides, renewables need not to be imported from foreign countries.

Fallacies

According the nuclear industry the potential of nuclear power for the future is big. This view is based on two premises: • trouble-free implementation of unproven technology• availability of inexhaustable uranium resources.How secure is the evidence on which these premises are based?Both premises turn out to be fallacies, for reason of ignorance of fundamental natural laws, especially the Second Law of thermodynamics.These premises will be discussed in separate sections [more i30.i38].

Après nous le déluge

A third factor, implicite and unspoken, strongly contributes to the optimistic view of the nuclear industry with regard to the potential of nuclear energy in the future: the systematic postponement of the back end activities to future generations. Massive efforts, requiring large investments, massive amounts of energy, materials and human resources, are needed to isolate the radioactive wastes from the human environment. Contrary to widely vented statements, no advanced technology is needed to solve the radioactive waste problem [more i16].

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i07

How clean is nuclear power?

Nuclear power is pointedly advertised as a clean energy source. Examination of the complete series of industrial processes needed to make nuclear power possible [more i12] reveals a picture of nuclear power completely different from the usual connotation of ‘clean’. The nuclear process chain consumes massive amounts of chemicals. From the basic laws of nature follows that losses and leaks are unavoidable, so a certain fraction of the used chemicals are inevitably discharged into the environment. Planned and unplanned dispersal of unwanted substances are exacerbated by economic pressure and imperfect human behaviour.

Greenhouse gases

The nuclear reactor is the only part of the nuclear system that does not emit CO2, all other parts do. Under the current conditions the specific CO2 emission of nuclear power is roughly 80-130 gram CO2/kWh. This figure will rise during the next decades, due to the depletion of high-quality uranium resources and dependency on ever decreasing ore quality [more i05].

Emissions of greenhouse gases other than carbon dioxide into the environment by the nuclear energy system are kept secret. However, in the front end processes of the nuclear chain massive amounts of fluorine (at least 130 tonnes per gigawatt.year (GWe.a)} and chlorine (at least 102 tonnes per GWe.a) are being consumed, either in elemental form or as compounds with other elements. In 2010 the world nuclear electricity generation was 316 GWe.a per year, so the global consumption of fluorine and chlorine in the nuclear system in 2010 were respectively 41000 and 32000 tonnes per year at least.Many gaseous chloro-fluoro-compounds are potent greenhouse gases. Emissions seem not only possible, but even likely, for no chemical plant is leak-proof.

Chemicals

In the industrial processes of the nuclear chain substantial amounts of chemicals are cunsumed [more i13]. Fluorine and chlorine are already discussed above. Per gigawatt.year (GWe.a) one nuclear power plant consumes in its process chain some 22000 tonnes chemicals, most of it for the extraction of uranium from the earth’s crust (mining and milling) and for the maintenance of the power plant itself. More than 17000 tonnes/GWe.a of these chemicals are routinely discharged into the environment, corresponding with 5.4 million tonnes per year by the global nuclear power fleet. Chemicals needed for mine area rehabiliation are not included in these figures. A small part of the discharged chemicals are environmentally harmless from a chemical viepoint, such as lime, most other are far from harmless. Besides the discharged chemicals are contaminated by radioactive substances and mobilized toxic elements.

Radioactive discharges

Releases of radioactive substances into the human environment occur in all phases of the nuclear process chain. Particularly the processes of the back end are potential sources of

28insights

substantial emissions of radioactivity, for these involve a billionfold of the amounts of radioactivity compared to the front end. The nuclear reactor and the back end processes discharge considerable amounts of radioactivity into the environment on routine base [more i17]. These emissions are going on day after day, year after year. Radioactive contamination is cumulative and irreversible.Usually the nuclear industry is concealing the radioactive emissions, or playing them down if disclosed nevertheless. Even authorized emissions of radioactive materials which are officially classified as harmless are proved to be harmful for people living in the neighbourhood of nuclear power stations. Serious are the massive radioactive contaminations as result of large accidents, such as Chernobyl and Fukushima [more i21, i43]. Accidents are unavoidable, as long as all human-generated radioactivity is not permanently isolated from the human environment. The chances of large nuclear accidents are increasing with time, due to several factors, such as: • increasing amounts of radioactive materials in an increasing number of temporary storage

facilities• progressive deterioration of the materials and structures of the temporary storage facilities• increasing economic pressure [more i26].

Ecosystem disturbances

As a result of nuclear power-related activities permanent disturbances of large area’s occur. Some disturbances are visible, for instance the mining areas of uranium and other consumables, other are not directly visible but become evident in the long term in an insidious way. Radioactive contamination is irreversible and accumulative. The adverse effects in humans have often long incubation times [more i22].Radioactive dust is spread by the wind over vast areas (hundreds of thousands square kilometers) around uranium mines [more i18]. In addition to radiological hazards, this dust contains biochemicall toxic substances and elements. Uranium and its decay daughters are from harmless even at very low concentrations. The groundwater tables in regions with uranium mines are irreversibly intoxicated with numerous kinds of chemically and radiologically hazardous substances.Large areas are affected by the routine releases of radioactive materials, especially by planned and unplanned releases from reprocessing plants [more i17,i19]. Due to accumulation in the food chain high concentrations of radionuclides are possible locally.Obviously severe nuclear accidents cause serious and permanent disturbances of vast areas by contamination by all kinds of radionuclides, rendering major parts of these areas (tens to hundreds of thousands square kilometers) inhabitable [more i21, i24]. A number of the radionuclides are difficult to detect by common radiation detectors.

Depletion of valuable materials

In the nuclear process chain a number of materials are consumed in a once-only mode. An example is zirconium, used for fabrication of the cladding of nuclear fuel elements. Due to its high radioactivity this zirconium is not recyclable. The zirconium consumption is nearly 50 tonnes/GWe.a, corresponding with some 16000 tonnes per year globally.Another example is bentonite, a clay mineral with special properties, which is needed to isolate radioactive waste from groundwater ingression for very long times. If all radioactive wastes from the nuclear chain would be conditioned properly, the consumption would be around 84000 tonnes/GWe.a, or more than 26 million tonnes per year globally [more i13].How large are the bentonite resources? How large are the areas disturbed by the mining of these amounts?

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i08

Unique features of nuclear power

Man-made radioactivity

An operating nuclear reactor produces heat and radioactivity, simultaneously, inextricably and irreversibly. The potential energy embedded in the nuclei of uranium atoms is converted into heat and nuclear radiation by fission of the nuclei. During the fission process tremendous amounts of radioactivity are generated. The amount of man-made radioactivity is a billion times the radioactivity of the fresh uranium entering the reactor.One reactor of 1 GWe generates each year as much radioactivity as 1000 exploded nuclear bombs of about 15 kilotonnes, the yield of the Hiroshima bomb.

All radioactive wastes ever generated during the nuclear era are still stored in temporary storage facilities. These facilities are leaking all kinds of radioactivity into the environment at an increasing rate, due to the unavoidable deterioration of the materials and structures of the containing facilities. The temporary storage facilities are vulnerable to accidents, terroristic attacks and natural disasters, as happened at Fukushima Daiichi.

Once generated, radioactivity cannot be influenced by any means. The radioactivity resulting from nuclear power decreases by natural decay only. For some components of the man-made radioactivity the decay rate can be measured in seconds to hours, for other components time scales of years to hundreds of thousands of years are involved.

Mobilisation of radioactivity

Uranium is a radioactive metal found in nature in various chemical forms in uranium ore. In uranium ore strata, uranium and its many radioactive decay daughters are bound in chemically stable minerals. This is not to say uranium-bearing rock is harmless to man, not at all.When uranium ores are disturbed to extract the uranium, the element is brought out of its geologic confinement into the environment and is chemically mobilised. The uranium isotopes are chemically separated from the separated radioactive daughters, containing about 85% of the radioactivity in uranium ore, which are dumped as mill tailings in huge ponds and spoil heaps. From then on the radioactivity from the uranium ore is mobile.The man-made radioactivity is also mobile: without active and dedicated precautions it will enter the human environment at some time [more i39, i43].

Metal as energy source

Uranium, the source of nuclear power is a metal, contrary to fossil fuels, which consist of burnable hydrocarbons. Fossil fuels can be used as found in nature. Uranium has to be extracted from rocks (ores) in the earth’s crust and purified to high degree by means of a sequence of technical and chemical processes. From the pure uranium nuclear fuel is produced in another sequence of chemical and physical processes.Uranium is almost exclusively used as energy source and has no other industrial applications.

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Time frame

The time frame of a nuclear project is extremely long. The construction of a nuclear power plant takes usually some 10 years. The nominal operational lifetime of a nuclear power plant is about 40 years. Once a nuclear reactor has started operating, society is committed to a long sequence of causally related and very demanding processes. Completion of this sequence may take 100 years. The complete time frame of a nuclear project, called the cradle–to–grave period, is estimated at some 150 years [more i12].

Complexity

The nuclear energy system is the most complex energy system ever, not only in technical sense, but also in economic, societal and political senses. The complexity has a profound negative effect on the controllability of nuclear power.

Irreversible consequences

The nuclear process chain encompasses several vulnerable phases with the potential of disasters of unheard magnitude, such as Chernobyl and Fukushima. The effects of nuclear disasters are irreversible because radioactivity cannot be destroyed nor made harmless to man. The health effects with people will remain visible for centuries to come. A disaster of the size of Chernobyl or Fukushima in Western Europe would have unimaginable consequences and does not need the explosion of a reactor. A large accident by whatever cause at a reprocessing plant or spent fuel storage facility could have even worse consequences [more i21].

The chances of occurence of large disasters are unkown. There are too many and too large technical uncertainties and variables regarding the processes in which highly radioactive materials are involved, to do a sound risk analysis. In addition the human factor in the broad sense of the word plays an important part. Practice is not encouraging: during the past 60 years two very large accidentsand a number of less grave accidents occurred, not counting the accidents which may have happened in the former Sovietunion before Chernobyl.If the aprèsnousledéluge paradigma keeps dominating the nuclear world, Fukushima will not be the last disaster of that kind.

frontend

© Storm

Figure 08-1. Heat and radioactivity, inextricably An operating nuclear reactor produces heat and radioactivity, simultaneously, inextricably and irreversibly.

The reactor is fueled by enriched uranium, produced from uranium ore in the well-established front end

processes of the nuclear chain. The heat is partially converted into electricity. What to do with the man-

made radioactivity is still an open-ended question.

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immobile to beimmobilised

mobilisation mobilemultiplicationx 1 billion

front end back end

© Storm

Figure 08-2. Mobilisation and generation of radioactivity Symbolic presentation of the radioactivity flow through the nuclear system. Thw flow starts with the

mobilisation of natural radioactivity and multiplies a billionfold by generation of radioactivity in the

reactor. Unavoidably a part of the mobilised radioactivity will be released into the human environment. A

safe immobilised end of the nuclear chain still exists only in cyberspace. What quantities of the radioactive

materials leaving the reactor will end up in the environment?

© Storm

Figure 08-3. Man-made radioactivity By fission of uranium in an operating nuclear reactor the radioacivity increases a billionfold. If the pea on

the foreground (diameter 1 cm) represents the radioactivity of fresh nuclear fuel, then the balloon at a

diameter of 10 meters represents the radioactivity of the spent nuclear fuel.

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20001960

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worldradioactivity

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Figure 08-4. World radioactivity inventory.All man-made radioactivity still exists in a mobile form in the human environment. The world inventory

of man-made radioactivity passed the 10 million nuclear bomb equivalent mark in 2010 and is rising

nearly linearly with 370 000 nuclear bomb equivalents a year. These amounts of radioactivity are stored

in temporary facilities, deteriorating with time, vulnerable to economic cutbacks, natural disasters,

accidents and terroristic attacks. A nuclear bomb equivalent is the amount of radioactivity generated at

the explosion of a nuclear bomb of 15 kilotonnes, about the yield of the Hiroshima bomb.

50 100 150

years from now

© Storm

back end

back end

operational lifetime


c2g period

c2g period

0

startup closedown

startup closedown

Figure 08-5. Cradle-to-grave (c2g) period Cradle-to-grave (c2g) period of fossil-fuelled and nuclear electricity generation. Assumed operational

lifetime of noth systems is 40 years. Construction period fossil: 5 years, nuclear: 10 years. Back end (waste

handling, decommissioning + dismantling) fossil: 5 years, nuclear: unknown, at least 60 years, possibly

more than a century.

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i09

Radioactivity

Isotopes

Atoms are composed of a nucleus with a positive electric charge surrounded by electrons with a negative charge. The negative charge equals the positive, so the atom is electrically neutral. The nucleus consists of protons (positive charge) and neutrons (neutral). The number of protons determines to which chemical element the atom belongs. The chemical properties of an atom are determined by the number of protons. The number of neutrons may vary; atoms with an equal number of protons but a different number of neutrons in the nucleus are called isotopes. The chemical properties of isotopes are identical. The nuclear-physical properties of an atom are partly determined by the number of neutrons. Some isotopes have an unstable nucleus.

Radioactive decay

Radioactivity is the phenomenon that unstable nuclei of atoms (radionuclides) spontaneously decays into another kind of atom, coupled with the emission of nuclear radiation: alpha, beta and/or gamma radiation. Alpha radiation consist of alpha (a) particles: helium-4 nuclei (2 protons + 2 neutrons) which are ejected from the decaying nucleus at very high speed. Beta radiation consist of beta (b) particles: electrons ejected from the nucleus at very high speed. Gamma radiation consists of gamma (g) rays, very energetic electromagnetic rays and much more penetrating than X-rays.

The decay product, also called the decay daughter, can be radioactive in itself or can be stable. In nature on earth a few radioactive kinds of atoms occur in low concentrations. Important with respect to nuclear power are the elements uranium and thorium, which are formed billons of years ago in supernova explosions. These radionuclides decay via a series of other radionuclides into stable lead or bismuth atoms. During fission of uranium large amounts of radioactive isotopes of nearly all known elements are formed.

Ionizing radiation

Nuclear radiation, also called ionizing radiation, strongly interacts with matter and is harmful to living organisms, for it destroys biomolecules. Alpha and beta radiation can be blocked by thick paper respectively aluminum foil, so these rays may seem not very harmful to man. However radionuclides radiating alpha or beta rays inside the human body are extremely dangerous, because the living cells are not protected by the skin or clothes. A dose of only a few nanograms of the alpha-emitter polonium-210 in the human body is lethal.A complicating factor is that alpha and beta radiation are not detectable by hand-held counters, which can only detect gamma rays. Radionuclides that emit weak or no gamma rays are invisible to these detectors. A number of biologically very active radionuclides fall within this category, such as tritium (radioactive hydrogen) and carbon-14 (radioactive carbon).

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Half-life

The rate of radioactive decay is characteristic to each kind of radionuclide and cannot be decelerated or accelerated by any means. Radioactivity cannot be destroyed nor made harmless to man and other living organisms. Radionuclides occurring in nature, such as uranium andthorium, have very long half-lifes measured in billions of years. These nuclides have been formed in stellar explosions long before the Earth came into being. Man-made radionuclides have much shorter half-lifes, ranging from seconds to millions of years. The specific radioactivity of a radionuclide with a short half-life is higher as the half-life is shorter.

Nuclear bomb equivalents

Nuclear power generates immense amounts of radioactivity, irrevocably and irreversibly. During fission of uranium atoms many dozens of different kinds of radioactive atoms are coming into being, called the fission products. In addition non-radioactive construction materials become radioactive by neutron radiation. The amount of man-made radioactivity is a billion times the radioactivity of the fresh uranium entering the reactor.One nuclear reactor generates each year an amount of radioactivity equivalent to roughly 1000 nuclear bombs of the yield of the Hiroshima bomb. All radioactive wastes ever generated during the nuclear era are still stored in temporary storage facilities. These facilities are leaking all kinds of radioactivity into the environment at an increasing rate, due to the unavoidable deterioration of the materials and structures of the containing facilities, and are vulnerable to natural disasters, accidents and terroristic attacks.

Once generated, radioactivity cannot be influenced by any means. The radioactivity resulting from nuclear power decreases by natural decay only. For some components of the man-made radioactivity the decay rate can be measured in seconds to hours, for other components time scales of years to hundreds of thousands of years are involved.

-emission helium-3 atomtritium atom

β

β

© Storm

Figure 09-1. Radioactive decay of tritium.Tritium, symbols T, 3H or H-3, is a heavy isotope of hydrogen, with one proton and two neutrons in the

nucleus. When a tritium atom decays, it emits a beta particle (an electron) at high speed. After decay

the nucleus contains two protons and one neutron, the nucleus of a helium-3 atom, which captures a

second electron and becomes a neutral helium-3 atom. The sums of electric charges remain constant and

a minute fraction of the mass is converted into energy.

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time t = 0 after 1 half-life period after 2 half-life periods

© S

torm

Figure 09-2. Decay of a radionuclide.One half-life period after creating of a given amount of a certain radionuclide at time t = 0, half of the

radionuclides has decayed into another kind of, non-radioactive, nuclides. A second half-life period later

half of the remaining radionuclides has decayed into stable nuclides. And so on. The total mass of matter

remains almost constant during the decay process.

Figure 09-3. Symbol of nuclear radiation.This pictogram symbolizes three kinds of lethal nuclear radiation: alpha (a), beta (b) and gamma (g)

radiation.

0 12.32 24.64 36.96 49.28 61.60

0.25

0.125

0.50

0

years

mass oftritium

1.00 © Storm

Figure 09-4. Half-life of the radioactive decay of tritium.Mass of a given amount of tritium as function of the time. After one half-life half of the initial number of

tritium atoms has decayed into helium-3 atoms. During the second half-life period half of the remaining

tritium atoms decay,not the other half of the initial amount of tritium atoms. Radioactive decay is a

stochastic process.

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worldradioactivity

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nuclear bombequivalents)

year

© S

torm

Figure 09-5. World radioactivity inventory.All man-made radioactivity still exists in a mobile form in the human environment. The world inventory of

man-made radioactivity passed the 10 million nuclear bomb equivalent mark in 2010 and is rising nearly

linearly with 370 000 nuclear bomb equivalents a year.

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i10

Radioactive materials

Spent nuclear fuel

Fresh nuclear fuel consists of uraniumoxide, packed in thin tubes of Zircalloy. The tubes are bundled into fuel elements. The uranium has been enriched in the fissile isotope uranium-235. Fresh nuclear fuel is weakly radioactive due to the radioactivity of the uranium atoms. During the fission process highly radioactive fission products and actinides are formed. When the fissile content of the nuclear fuel decreases below a certain level the fission process cannot sustain itself and the fuel is removed from the reactor as spent nuclear fuel. Spent fuel is extremely radioactive and generates much heat, due to the radioactive decay of its contents. The material has to be cooled in spent fuel pools for many years to prevent melting and consequently the release of the contents into the environment. More than 90% of the man-made radioactivity generated during fission is contained in the spent fuel elements.

Fission products

Fission products are the atoms resulting from the fission of uranium atoms. Nearly all elements of the Periodic System are represented in the mixture. A substantial fraction of the fission products are highly radioactive, with half lifes varying from seconds to millions of years.During the first four centuries after removal from the reactor, the radioactivity of spent sfuel is mainly determined by the fission products.

Actinides and minor actinides

Actinides are radionuclides formed from uranium atoms by neutron capture and have a higher atom number (= number of protons in the nucleus) than uranium. First neptunium atoms are formed, which quickly decay to plutonium atoms. By repeated neutron capture the plutonium atoms are transmutated into still heavier atoms, These elements, including plutonium, are often called the actinides and do not occur in nature. The minor actinides are the radionuclides beyond plutonium, such as americium, curium and californium. All actinides are highly radioactive and most of them emit dangerous alpha rays and gamma rays. A number of the minor actinides exhibit spontaneous fission, causing neutron radiation and complications in an operating reactor. One of the americium isotopes has a critical mass of some 7 grams under certain conditions. The half-lifes of the minor actinides vary from a few decades to millions of years.

Activation products

In addition to fission products and actinides a third category of radioactive atoms are generated in an operating nuclear reactor: activation products. By neutron irradiation non-radioactive construction materials become radioactive, often with very long half-lifes.

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naturalspecific radioactivityof the human body

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Radioactive decay of LWR spent fuel 33 GW(e).day/Mg

total activity

actinides

fission products

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orm

Figure 10-1. Radioactive decay of spent nuclear fuel over timeThe specific radioactivity, in gigabecquerel per kilogram (GBq/kg), of spent fuel. Note that both axes have

logarithmic scales. Each scale division denotes a factor ten. With a linear time scale the horizontal axis

would be about 100 kilometers long. On the horizontal axis a reverse historic timescale is indicated, to

give an idea of the time frames involved. The green line indicates the natural radioactivity of the human

body (143 Bq/kg). The orange line indicates the lethal amount of radioactivity in the human body.

Nuclear fuel from the new types of nuclear reactors has considerably higher burnup than the fuel this

diagram is based on and so its specific radioactivity is considerably higher. The contributions tritium,

carbon-14 and of activation products are not included in these curves.

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i11

Radioactive waste streams

In effect all radioactive materials resulting from the operation of a nuclear power plants is waste, for it cannot be recycled, except plutonium. The generation of human-made radioactivity is irriversible. Several different radioactive waste streams can be discerned originating from the nuclear energy system:• Mining waste• Operational waste• Routine releases• Spent fuel• Decommissioning and dismantling waste

Mining waste

Uranium ore always contains a number of other radioactive elements, a part of which are alpha-emitters. In the extraction process the uranium is separated from all other elements, which are disposed of in the mining waste, called mill tailings, a mud of finely ground ore, chemicals and water. The mud is stored in large ponds. The water from the ponds, containing the radioactive elements plus a number of toxic chemicals, seep into the ground, contaminating the groundwater table over large areas. When the water of the storage ponds has evaporated, after the mine has been depleted and abandoned, the fine powder is blown away by the wind over large distances. Most uranium mines are located in arid areas. Hundreds of thouands square kilometers are contaminated with dangerous alpha emitters. This waste stream is not classified as ‘nuclear waste’ by the nuclear industry.The consequences of this practice are not investigated by the nuclear industry. Evidence from local residents point to seriously adverse health effects of the chronic exposure to the low concentrations of the dangerous radionuclides in the dust and groundwater [more i18].

Operational waste

All activities and industrial processes involving radioactive materials generate radioactive waste. Usually this waste is packed in drums or concrete casks and stored in temporary storage facilities. It may contain all kinds of hazardous radionuclides, fission products, actinides and activation products, in relatively low concentrations, but nonetheless hazardous.

Routine releases

A part of the man-made radioactivity is released into the environment routinely, because complete confinement is practically not feasible or is too costly. Nominally operating nuclear power plants discharge large amounts of tritium and carbon-14 into the environment, for these radionuclides are difficult to retain. Officially these radionuclides are rated low-risk, because of their low-energy beta emission. Evidence points otherwise: in the vicinity of nuclear power stations a significantly higher incidence of cancer and leukemia with young childern is proved to occur [more i11, i23, i24, i25].

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Reprocessing plants (La Hague, France and Sellafield, UK) discharge huge amounts of radioactive wastes into the environment (air and sea), comprising all gaseous radionuclides plus the radionuclides which are difficult to retain by fixation in stable chemical compounds. In addition the unavoidable waste streams of the separation processes, containing all kinds of radionuclides from spent fuel, are partly discharged into the sea [more i31]. This practice may be dictated by economic arguments [more i26].

Spent nuclear fuel

In principle the nuclear industry does not consider spent nuclear fuel to be waste, because of the plutonium it contains. Plutonium could be used in closed-cycle modes of the nuclear energy system. The closed-cycle mode implies reprocessing of the spent fuel, a costly process with large=volume waste streams and accompanied by massive discharges of radioactivity into the environment. In practice only rcycling plutonium into a small number of conventional light-water reactors (LWRs) occurs. The gain does not balance the extra energy investments and costs of reprocessing [more i31]. The ultimate goal of reprocessing, establishment of the breeder reactor, proved to be unfeasible. For that reasons spent nuclear fuel has to be classified nuclear waste.

Spent nuclear fuel contains more than 90% of the man-made radioactivity generated during the operation of a nuclear reactor and produces considerable amounts of residual heat, due to the decay of its radioactive contents. For decades after removal from the reactor spent fuel has to be cooled to prevent meltdown. For that reason spent fuel is stored in cooling ponds adjacent to the reactors or at reprocessing plants. After a long cooling period storage in air-cooled dry casks is also practicized.Classified as most dangerous, usually nuclear industry has only spent fuel in mind when talking about nuclear waste. Although the radioactivity of spent nuclear fuel decreases with time, it is still dangerously high after tens of millions of years [more i10].

Decommissioning and dismantling waste

As a result of the intense neutron radiation during the fission process a nuclear reactor and its associated appendages become strongly radioactive. After closedown of the power plants the so-called nuclear island has to be decommissioned and dismantled. These activities generate very large volumes and masses of radioactive waste: tens of thousands of tonnes and tens of thousands of cubic meters [more i20]. The specific radioactivity of these wastes (measured per tonne waste), containing not only activation products, but also fission products and actinides as a result of contamination during the operational lifetime, is lower than that of spent nuclear fuel, but the total content of radioactivity is very large and long-lived. The waste is dangerous to man even after millions of years.

Isolation from the human environment

Radioactivity cannot be destroyed nor made harmless to humans. To prevent large populations, for example Europe or the USA, from being exposed to ever-increasing amounts of radioactivity, all radioactive wastes have to be isolated from the biosphere forever. That means that the waste has to be stored in such way that it will take millions of years before the radioactivity can re-enter the human environment by natural processes, for example via groundwater flows. The chances of re-entering radioactivity should be reduced to any conceivable minimum. Even then enough unknowns will remain which will enhance those chances and reduce the safety of the pemanent nuclear waste storage. Economic priorities might pose a serious threat [more i26].

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Geologic repository

The definitive storage facility for radioactive waste is envisioned as a mine deep (500 meter or more) in a very stable geologic formation. Which geologic formations are best suited to accomodate a geologic repository? Each country seems to answer this question on its own way, dependent on the geologic options present and the political situation of the moment. For example, in the Netherlands and in Germany salt domes are discussed, in Belgium and France old clay formations, in the USA a volcanic formation (recently cancelled, without naming a new option) and in Sweden, Finland and Switzerland granitic formations.

After placing the radioactive waste in the mine, the galeries and caverns have be filled up with bentonite and other materials to prevent migration of radionuclides dissolved in groundwater entering the storage facility. Water ingression will almost certainly happen, sooner or later.

At present all nuclear wastes are stored in provisional and temporary storage facilities. The costs of the construction and operation of one geologic repository will be very high, likely counted in tens of billions of euros [more i16]. To store the yearly production of radioactive waste of the world, every two years a new geologic repository has to be opened. None exists in the world today.

Mine rehabilitation

The weakly radioactive but nevertheless dangerous mining wastes have to be isolated from the biosphere (atmosphere, groundwater) too. This process, called mine rehabilitation, is still not practicized in the world [more i18].

uranium ore

fossil fuels

construction materials

auxiliary materials

chemicals

dismantling wastes

spent fuel (stored)

gaseous effluentsaerosols

liquid effluentssolid wastes

reusablematerials

non-radioactivewastes

operational releases liquid effluents

radioactivewastes

nuclear systemradioactivity generator

gaseous effluents, aerosolsCO , CFCs, other greenhouse gases2

©Storm

Figure 11-1. Waste streams of the nuclear system.The nuclear energy system generates non-radioactive waste streams, which are not discussed here except

CO2, and radioactive waste streams. The man-made radioactivity of 1000 nuclear bomb equivalents per

year is distributed over very large volumes and masses of solids, liquids and gases. Considerable amounts

of radioactive waste are discharged into the human environment. Not a single kilogram of radioactive

waste ever generated has been safely isolated from the biosphere.

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fission products

fission products

33 g U-235

8 g uranium-235

967 g U-238 943 g U-238

plutonium

uranium-236

fresh fuel reactor spent fuel1.000 kg1.000 kg

0.65 g

4.6 g

8.9 g

20.4 g

minor actinides

14.6 g

© Storm

Figure 11-2. Composition of fresh and spent nuclear fuel.Fresh nuclear fuel consists of very pue uranium, enriched in the fissile uranium-235 isotope. During

operation of the reactor a part of the U-235 nuclides are fissioned. a part is converted into non-fissile

U-236 and a part has not fissioned when the fission process is no longer sustainable and the fuel has to be

removed from the reactor. By neutron capture - the neutrons coming from fissioning nuclides – a small part

of the non-fissile U-238 isotope are converted into fissile and non-fissile plutonium isotopes. A part of the

formed plutonium is fissioned and so contributes to the energy production. Another part of the plutonium

is converted into the minor actinides: nuclides with a higher atomic number than plutonium, having nasty

properties. The radioactivity of 1 kg spent fuel is a billion times higher than of 1 kg fresh fuel.

In reality the constituents of fresh and spent nuclear fuel are mixed on atomic scale, so it is not possible

to cut out a few pieces from spent fuel to obtain all fission products, plutonium and minor actinides in

separate blocks. Separation of these materials requires a complicated sequence of processes, called

reprocessing [more i31 and i42].

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Figure 11-3. Geologic repositorySymbolic presentation of a geologic repository for radioactive waste. The purpose is to isolate the

radionuclides from the biosphere for geologically long periods.

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Figure 11-4. Geologic repository.The Swedish KBS concept for deep geological disposal of spent fuel. According to this concept the spent

fuel would be packed in durable canisters, with thick outer layer of very pure copper, which are to be

placed in holes in the floor of galleries of a deep mine in granite. The holes and the galleries are to

be filled up with bentonite, a mineral which would retard the migration of radionuclides from leaking

canisters by groundwater. In the long run, how long is unknown, all canisters will go leaking. Radioactive

wastes with lower specific radioactivity would be packed in concrete canisters and stored in large caverns,

which would be also filled up with bentonite (not pictured here).

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i12

Life cycle analysis of the nuclear energy system

Nuclear process chain

A nuclear power plant is not a stand-alone system, it is just the most visible component and the midpoint of a sequence of industrial processes which are indispensable to keep the nuclear power plant operating. This sequence of industrial activities is called the nuclear process chain. Like most industrial processes the nuclear chain comprises three sections: the front end processes, the production process itself and the back end processes. This can be compared with a common sequence of household activities: preparing a meal, enjoying the meal and washing the dishes and cleaning up. The front end of the nuclear chain comprise the processes to produce nuclear fuel from uranium ore and are mature industrial processes. The midsection encompasses the construction of the nuclear power plant plus operating, maintaining and refurbishing it. The back end comprises the processes needed to handle the radioactive waste, including dismantling of the radioactive parts of the power plant after final shutdown, and to isolate it permanently from the human environment. The most important back end processes are still existing only on paper.

Cradle to grave

Comparison of the diverse implications of different energy systems (nuclear, fossil, renewables) is possible only on basis of life cycle assessments of the full process chain of each energy system, from cadle to grave. Implementation of a given energy system has various aspects, for example concerning issues of economy, environment, safety, politics, society and availability of natural resources. These aspects are rarely observable at the same time.The cradle-to-grave period of an energy system is the period from the start of a given project through restoration of the site to greenfield conditions. The cradle-to-grave periods of the various energy systems, each type with an assumed operational lifetime of 40 years, vary from some 50 years for fossil-fuelled and renewable power stations to 100-150 years for nuclear power stations.

Energy balance of the nuclear system

Any industrial process consumes energy and materials. The sole purpose of the nuclear energy system, consisting of the reactor plus the industrial processes needed to generate electricity from uranium ore and handle the radioactive waste, is to deliver useful energy to the consumer. A conditio sine qua non for the nuclear energy system is that its indispensable assembly of industrial processes consumes less useful energy than is generated by the reactor. In other words: the net energy balance of the nuclear system should be positive. This condition is analogous to that of a viable economic activity, which should have a positive financial balance.

The energy investments of the nuclear system from cradle to grave turn out to comprise five main components of similar magnitude: • construction of the power plant,

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• front end, from ore to fuel,• reactor operation, maintenance and refurbishments (OMR), • back end, definitive removal of all radioactive waste from the human environment,• reactor decommissioning and dismantling.Analysis of the complete nuclear system proves that the choice of enrichment technique, diffusion or ultracentrifuge, has a negligible impact on the energy balance of nuclear power.

The energy balance of the nuclear system turns out to be not a constant factor, but depending on a number of variables.The operational lifetime of the reactor, measured in full-load years, determines the gross energy production of the nuclear system.At low ore grades the thermodynamic quality of uranium resources from which the nuclear system derives its uranium becomes a dominant variable of the energy investments for the front end and the back end of the nuclear process chain [more i38].The figures of the construction energy investments exhibit a considerable spread. Large uncertainties exist with respect to the last phase of the nuclear chain: decommissioning and dismantling of the reactor. Preliminary estimates point to a multiple of the construction energy investments.

Full-load years and energy payback time

A full-load year is equivalent with maximum amount of electricity delivered to the grid, if a nuclear power plant would operate at 100% of its nominal capacity during a full year without interruptions. A nuclear power plant which operated with an average load factor of 70% during a period of 30 years has an operational lifetime of 21 full-load years. The number of full-load years is a vital quantity for the calculations of the energy balance, the energy payback time and the energy return on energy investment. The energy payback time is the number of full-load years a certain reactor has to operate to generate as much useful energy as has been invested to construct and operate the system.The energy payback time of the currently operating nuclear energy systems, measured over the full cradle-to-grave period, is about 9 full-load years at the current world average uranium ore grade. The average operating lifetime in 2011 of the world operating nuclear fleet was about 21 full-load years.

Energy return on energy investment EROEI

The energy return on energy investment (EROEI) is here defined as the ratio of the energy delivered to grid over the energy investments, both measured over the full cradle-to-grave (c2g) period.The energy return on energy investments of the world averaged nuclear energy systems are EROEI = 2-3 under the current conditions, but will decline over time when leaner uranium ores are to be exploited [more i38].

Methodology of energy analysis

To assess the physical aspects of the nuclear energy system a comprehensive energy analysis of the system is required. The analysis starts with a life cycle assessment (LCA), to describe all processes comprising the nuclear system, the nuclear process chain. Each process of the chain is analyzed separately: the inputs of materials and energy are quantified per unit product. The direct inputs of useful energy (electricity and fossil fuels) are analyzed, but also the indirect energy investments, which have consumed for the production of the materials needed for the

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observed process.The production of one kilogram of steel from iron ore, for example, consumes a certain amount of useful energy; this amount is called the embodied energy of steel.

uranium ore deep geologic repository

front endprocesses

electricity

back endprocesses

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cooking the meal enjoying the meal washing the dishes + clearing the mess

Figure 12-1. Nuclear process chain.Broad outline of the nuclear process chain, also called the nuclear energy system. The three main parts

are the front end processes, the powerplant itself and the back end processes. For more details see text.

50 100 150

years from now

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back end

back end



c2g period

c2g period

0

startup closedown

startup closedown

Fugure 12-2. Cradle-to-grave (c2g) period Cradle-to-grave (c2g) period of nuclear electricity generation compared to fossil-fuelled electricity.

Assumed operational lifetime of both systems is 40 years. Construction period fossil: 5 years, nuclear:

10 years. Back end (waste handling, decommissioning + dismantling) fossil: 5 years, nuclear: unknown,

at least 60 years, possibly more than a century. The full timeframe of a nuclear project may run to more

than a century.

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time

duringoperationallifetime

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construction

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dismantling+ back end

cradle-to-graveproduction ofuseful energy

cradle-to-graveinvestments ofuseful energy

cumulativeenergy

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Figure 12-3. Dynamic energy balance of the nuclear energy system.During the construction phase useful energy is invested into the nuclear energy system. During the

operation phase useful energy is produced (electricity), but a part of the produced energy is required to

run the front end processes: the production of nuclear fuel from uranium ore. The energy requirements of

the back end processes (waste management, decommissioning and dismantling) are to be invested after

closedown of the nuclesar power station. The energy requirements of the back end are called the energy

debt, for these are still to be invested during the century following closedown. This diagram is at scale.

2010

1

2

EROEIof

nuclear power

3

2030 2050 2070year

2090

energy sink

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Figure 12-4. The energy return on energy investment(EROEI) of nuclear power.The energy return on energy investment (EROEI) is here defined as the ratio of the energy delivered to grid

over the energy investments, both measured over the full cradle-to-grave (c2g) period (see also Figure 12-

3). At EROEI = 1 the nuclear energy system consumes as much useful energy as it produces. Below a value

EROEI = 1 the nuclear energy system becomes an energy sink, instead of an energy producer. This graph

applies to a nuclear power plant of the current state of technology under favourable conditions. It turns

out that the year of the plunge into the energy sink does virtually not depend on the assumed parameters

of the nuclear reactor, but mainly on the quality of the available uranium resources. This is another way

to present the energy cliff [more i38].

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process

processed materials

raw materials

human labour

capital goods

services

electricity

waste heat

product

CO2fossil fuels

embodied energy

© Storm

liquid and solid wastes

gaseous effluents

Figure 12-5. Outline of the methodology of energy analysis.This outline pictures the inputs and outputs of materials and energy of a generic industrial process. The

input of services, processed materials and capital goods represent an indirect (embodied) energy input.

Human labour and raw materials are not attributed embodied energy.

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i13

Materials and nuclear power from cradle to grave

Comparison

The nuclear process chain, the technical system making nuclear power possible, comprises a number of industrial processes, each of which requires the input of ordered materials, such as chemicals and construction materials. All materials entering the nuclear system end up in the biosphere in some form: the mass of the output equals the mass of the input.

A part of the output mass is discharged into the environment as wastes: solids, liquids and gaseous effluents. Another part is recyclable and reenters the economic production system. A third part has become radioactive and has to be removed from the human environment forever. In addition to these three mass flows the nuclear system mobilizes large quantities of raw materials (waste rock, uranium ore) during the uranium mining activities.

How does the specific material consumption, measured from cradle to grave and normalized to gram per delivered kilowatt-hour, of the nuclear energy system compare to the specific material consumption of renewable energy systems, for example wind turbines?For this comparison we choose two reference systems, a nuclear energy system and a wind energy system of the same power capacity, each based on the most advanced currently proven and operational technology.

Not included in the material balances of both systems are:• materials required for mining and processing of the construction materials • materials for the distribution grid• materials for maintenance and refurbishments of the systems.Here we limit the scope to the nuclear-specific mass flows. Nuclear specific are the need for a mineral energy source (enriched uranium), the need for cooling water and the need for definitive isolation of the radioactive waste from the biosphere.

Specifications of the reference nuclear power system

PWR, pressurized water reactor, nominal power capacity 1 GWe,operational lifetime 24.6 full-power years, (current world average: 22 FPY) corresponding with 30 calender years at average load factor of 0.82lifetime elctricity production E = 215.5 billion kWhtotal construction mass 1 035 000 tonneslifetme nuclear fuel consumption natural uranium 5212 tonnes (current world average: about 6000 tonnes) zirconium 1218 tonnesassumed uranium resource ore grade 1 kg uranium per tonne rock (0.1% U) (current world average 0.1 – 0.05% U)

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open pit mine, stripping ratio 3, that means 3 tonnes of waste rock to be removed per tonne ore

Materials balance of nuclear power from cradle to grave

Not included in the material balance of nuclear power, in addition to the items cited above, are:• cooling water of the nuclear power plant during its operational lifetime and during waste

processing,• construction materials, chemicals and fresh water needed for interim storage of spent

nuclear fuel during at least 30 years; these are also left out of the material balance, due to lack of published operational data,

• diesel fuel consumed in mining operations (uranium, bentonite), transport and excavation of the geologic repositories.

milliontonnes g/kWhconstruction materials nuclear power plant + waste containers 1.45 6.7uranium ore (0.1% U) 5.61 26.0chemicals front end + back end 0.72 3.3bentonite , mine rehabilitation + backfill repository 2.06 9.6sand, backfill repository 2.00 9.3fresh water, uranium mining 3.70 17.2 sum materials + chemicals 9.93 71.9

rock excavated, uranium mining + waste repository 21.8 101

A major part of the construction materials, about 1 million tonnes, is basically recyclable, if the reactor has operated nominally. All other materials of the table above are lost forever because of radioactive contamination. The lost materials include the high-grade materials of the reactor and its appendages and the zirconium of the nuclear fuel cladding. The bentonite and sand are used to isolate the radioactive wastes from the biosphere in the depleted mining pit and in the waste repository [more i11, i18].The amounts of chemicals needed for the extraction of uranium from the earth’s crust increase with time due to the declining grades of the still available uranium ores [more i38].

Specifications of the reference wind power system

Wind park of 200 wind turbines of 5 MWe each nominal power capacity 1 GWe operational lifetime offshore 6.6 full-power years corresponding with 20 calender years at average load factor of 0.33 onshore 5.2 full-power years corresponding with 20 calender years at average load factor of 0.26 lifetime elctricity production offshore E = 57.82 billion kWh onshore E = 45.55 billion kWh total construction mass offshore 600 000 tonnes (1500 tonnes each turbine) onshore 300 000 tonnes (750 tonnes each turbine)

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Materials balance of wind power from cradle to grave

milliontonnes g/kWhconstruction materials wind park offshore 0.60 10.4 onshore 0.30 6.6

These materials are basically recyclable, especially the high-grade materials of the generator.

constr. materials

constr. materials

chemicals

uranium ore26.0

17.2

6.7

3.3

9.6

101 gram/kWh

gram/kWh

6.6

gram/kWh

waste rockbentonite

1 kWh electricity

radioactivity

1 kWh electricity

fresh water

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nuclear powersystem

wind powersystem

Figure 13.1

Consumption of materials by a nuclear energy system and an onshore wind energy system, both at 1 GWe

capacity, from cradle to grave. Materials for maintenance and refurbishments of both systems are not

included. For details see text. The materials of the wind system are basically recyclable at the end of its

operational lifetime. The materials consumed by the nuclear system are lost forever due radioactivity,

except 4.6 grams/kWh of construction materials.

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i14

Nuclear safety

Nuclear safety, or better: safety of nuclear power, is a complex issue, involving all aspects of nuclear power which could inflict directly or indirectly harm to the health and wellness of people and/or damage to material belongings.

Military and civil nuclear technology are inseparable

Military and civil nuclear technology are inseparable. Military applications (weapons, nuclear propulsion) are not discussed here. However, civil nuclear technology can be used for military purposes: if this happens in unfriendly countries the notion proliferation is often used. Another (semi) military threat which may originate from civil nuclear technology are terroristic actions with primitive nuclear weapons made from civil MOX fuel.

Proliferation

It is possible to apply civil nuclear technology to create nuclear weapons. By means of commercial enrichment bomb-grade uranium-235 can be produced (the fissile isotope of uranium). In research reactors bomb-grade plutonium can be generated from non-fissionable uranium-238. In a reprocessing plant the plutonium can be separated from the uranium and fission products. If the process is aimed at the production of weapon-grade plutonium the irradiation time of the nuclear fuel is kept short and the reprocessing of the spent fuel is not extremely demanding. The technology needed to make nuclear bombs from the fissile material seems to be available outside of the established nuclear-armed countries.

Nuclear terrorism and MOX fuel

Plutonium recycling in light-water reactors (LWRs) using MOX fuel (Mixed OXide) unavoidably generates uncontrollable risks of nuclear terrorism and proliferation. Using elementary che-mistry MOX fuel can be separated into uranium and plutonium. The plutonium could be used to produce a crude nuclear weapon. Evidently such a weapon wouldn’t have the reliability and yield of a military weapon, but even a nuclear explosion of a few kilotons in a town may be devastating. Even without a nuclear explosion the dispersion of several kilograms of plutonium over a town by a small plane may render the town inhabitable.

Reactor safety studies

Three major Probabilistic Risk Analyses (PRAs) on reactor safety have been done by the US Nuclear Regulatory Commission (NRC), the first being the famous ‘Rasmussen report’ in 1975. In a PRA the chances are calculated of the random failure of one component of a technical installation, in this case a nuclear reactor with its appendages, and the conceivable consequences of that failure for the performance of the installation as a whole.The results seem to be adopted as standards for other safety studies in Europe. The scope of these official studies is limited:

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• Only Light-Water Reactors (LWRS) of US origin have been analyzed. So the results cannot be applied to other reactor types, for example heavy-water reactors, high temperature gas-cooled reactors or liquid-metal cooled fast reactors, nor to reactors from other vendors (Russia, China, Korea, India).• The methodology of Probabilistic Risk Analyses does not cover all kinds of events that could cause a severe reactor accident.• Other processes of the nuclear process chain, particularly those involving spent fuel, are not included in the published official studies. The emphasis on the reactor safety may partly prompted by the high public visibility of nuclear reactors. The back end processes are nearly invisible to the public but not necessarily less dangerous. On the contrary.

In the USA the Nuclear Regulatory Commission is found to be highly reliant on information from licensee risk assessments. There are no PRA standards, no requirements for licensee’s PRAs to be updated or accurate, and the quality of the assessments varies considerably among licensees. How is the situation in other countries?

Safety of nuclear power is an exceedingly complex issue, involving a lot more constributing factors than the chance of severe accidents caused by random technical failures. Non-technical factors could initiate severe accidents as well, as proved by the Chernobyl and Fukushima disasters. Nuclear safety comprises more than a few theoretical studies on reactor failure modes.

Spent nuclear fuel pools

Spent fuel cooling pools are high-risk facilities in the nuclear process chain, because they usually contain the spent fuel of many years of reactor operation, involving many thousands of nuclear bomb equivalents, and are vulnarable to accidents. If the cooling fails during a critical period (may be a number days, may be shorter) the pool may boil dry resulting in a meltdown of the spent fuel. This in turn may initiate a criticality event, with uncontrolled fission in the (partially) molten fuel. This happened at Fukushima reactor 3 in 2011. Because spent fuel pools are located outside of the safety containment if the reator, radioactive materals are released unhinderedly.Spent fuel pools at reprocessing plants contain many 10 000’s ofnuclear bomb equivalents and may be the most dangerous places in the nuclear world.Safety studies did not include spent fuel storage facilities.

Nuclear safety is not set by safety studies but by practice

To many people the terms ‘safety’ and ‘safe’ may have a connotation of ‘little chance of accidents’ and/or ‘safeguarding against adverse consequences’. Think for example of the perception of safe airliners, of safety in the street (meaning ‘little or no criminality’) and of safe cars, meaning that the occupants are protected against the effects of an accident.The nuclear industry claims that nuclear power is safe with safe nuclear reactors. In their view the chance of a major reactor accident, involving a core meltdown (the worst case scenario), is one in the several millions of years. Negligible compared to other risks, posed by other events in the society, is said. The claim of safe reactors by the nuclear industry is based on a small number of theoretical studies [more i15].Empirical evidence proves the results of the reactor safety studies to be of little meaning. During the past decades three major reactor core meltdowns occurred: Three Miles Island (1979), Chernobyl (1986) and Fukushima (2011), a chance of once every 10-20 years.

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Main safety concern: dispersion of radioactivity

A unique feature of nuclear power is the generation of huge amounts of man-made radioactivity. All radioactivity is harmful and dangerous to humans. Apart from military and terroristic nuclear explosions, the safety issue of nuclear power concerns the possibilities of dispersion of the radioactivity into the human environment and the exposure of millions of people to radioactivity, leading to insidious and not seldom fatal diseases, usually after a long time delay.

This threat exists every day and involves vast and densely inhabited regions of the world: all regions with nuclear power stations and/or activities related to nuclear power. In addition the chance of releases of massive amounts of radioactivity increases year by year, due to:• rapidly increasing amounts of human-made radioactivity: 370000 nuclear bomb equivalents

per year are added to the world inventory,• increasing number of temporary and vulnerable storage facilities,• unavoidably progressive deterioration of the confinement of the stored radioactive materials

[more i39, i43].• increasing economic pressure, the more so in times of crisis, leading to less than optimal

handling of the radioactive wastes.

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i15

Engineered safety

Quality requirements

No technical system is perfect. In every production plant at any moment something may going wrong: a leaking coupling, a stuck valve, a bad electric contact, or whatever. Generally such failures can be ironed out without interruption of the production process or without endangering the personel. In a nuclear plant the health risks are much larger than in conventional plants. A small spill, only a nuisance in a conventional plant, may have serious consequences in a nuclear plant. For that reason the quality specifications for materials, control systems and personel in a nuclear plant and other nuclear facilities, such as reprocessing plants, are considerably higher than in non-nuclear plants.

High quality specifications mean a high degree of predictability of the properties and behavior of materials and structures. The higher the specifications the lower the tolerance for random occurrences, for impurities in the materials and for deviation from the dimensional specifications of the structures. High quality standards can be met by stringent control during the production process and by a large input of energy, most of it embedded in materials and specialized equipment. From the Second Law [more i41], it follows that the energy inputs exponentially increase with increasing quality specifications of a given amount of material or piece of equipment.

Bathtub hazard function

The risks for catastrophic breakdown of technical devices, including nuclear reactors, change as the devices age, much like the risks for death by accident and illness change as people get older. There are three distinct stages in the lifetime of a technical system or living organism: • the break-in phase, also called the burn-in phase or the infant mortality phase,• the middle life phase, also called the useful life,• the wear-out phase. The risk profile, the total failure rate as function of the time, for these three phases curves like a bathtub. Applied to technical devices only, the bathtub curve may be considered to be the sum of three types of failure rates. Obviously, the boundaries between the three life phases are not sharp.

• Early life (‘infant mortality’) failures, caused by bad design, defective manufacturing, material imperfections, faulty installation, unanticipated interactions, poor workmanship imperfect maintenance. and ineffective operation. The failure rate of this type decreases with time. The steepness of this curve depends on factors such as the amount of ‘pre-flight’ testing and the effectiveness of the quality control during manufacturing.

• A constant rate of random failures during working life, caused by accidents and random events. The height of this rate depends on, among other, the quality of the materials, of the design and the professionalism of the operators.

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• Wear-out failures, caused by ageing, deterioration of materials, etcetera. The rate increases with time. Wear-out failures are typically the consequences of Second Law phenomena [more i39, i41]. The concepts behind the bathtub curve are playing an important part in space technology. The reliability and predictability of the behavior of each component of a spacecraft or launch vehicle has to be extremely high to achieve a specified reliability of the complex assembly as a whole: the spacecraft or launch vehicle. Extensive testing and screening procedures are applied to pass all components and assemblies through the break-in phase and to eliminate design flaws, manufacturing defects, etcetera. Functional flexibility by redundancy in the design of the spacecraft systems and very high quality standards minimalize the occurence of random failures and postpone the wear-out failures. Exhaustive screening and pre-flight testing and stringent quality control make spacecraft possible to function unattendedly for a decade or longer. The effort needed to achieve such a level of reliability is exceedingly large, a direct consequence of the Second law. Large efforts mean high input of energy, materials and human resources, and consequently high financial cost.

Bathtub curve and nuclear technology

In the commercial nuclear technology no ‘pre-flight’ testing occurs. A nuclear power plant is assembled at the location chosen by the utility which will operate the plant. Design flaws and manufacturing defects are uncovered during construction and the first several years of operation of the nuclear power plant: the burn-in phase. Historical evidence indicates the burn-in phase of nuclear power plants to be several years. Major failures of nuclear reactors, including Three Mile Island 2 and Chernobyl, occurred during the burn-in phase.

Exactly the factors contributing to the burn-in phase failures are the cause of massive cost overruns of nuclear power plants and other large technological energy projects, as analyzed by the RAND Corporation . Recent examples of above mentioned habit of the nuclear industry, building before testing, are the troubled construction of the EPRs at Olkiluoto in Finland and at Flamanville in France, causing dramatic cost overruns and time delays.

Ageing processes of technical systems are consequences of the Second Law and are difficult to detect because they usually occur on the microscopic level of the inner structure of materials. The number of incidents and reportable events will increase. In addition, the aging process is leading to the gradual weakening of materials that could lead to catastrophic failures. Most notable among these processes is the embrittlement of the reactor pressure vessel. Failure of the pressure vessel of a PWR or BWR inevitably leads to a catastrophic release of radioactive material to the environment.

No human-made structure can be made absolutely fail-safe during tens of years. In the first place accidents and random events are impredictable by definition. The quality of the properties and the behavior of materials and structures predictably decline with time by ageing, cracking, wear, corrosion and other Second Law phenomena: the rate of wear-out failures predictably increases with time.

Preventable accidents

By the nuclear industry the Fukushima disaster is classified as a ‘preventable’ accident. What does that mean? Does this classification suggest that nuclear power is safe, despite the large accidents? Nearly all accidents involving technical installations are preventable, in principle.

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We only need 100% perfect engineering, 100% perfect materials and 100% perfect monitoring and maintenance. In practice we have to do with the natural phenomena which cause the bathtub curve.

Inherentlysafenuclearpowerisinherentlyimpossible.

time

random failures

failurerate

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wear o

ut fa

ilure

searly life failures

observed failures

Figure 15-1. Bathtub hazard curveThe bathtub hazard curve is the sum of three types of failures rates: the early life failures, decreasing

with time, the random failures, constant over time, and the wear out failures, increasing over time. The

bathtub curve is valid for technical devices, including nuclear installations, as well as for living organisms.

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i16

Energy debt

Energy on credit

The back end processes of the nuclear energy system are still in their infancy. Completion of these processes are mandatory to keep vast and densily populated regions habitable. The timescale of the completion of the downstream processes might run into a century or more. Unfortunately this completion is systematically deferred to the future.

The efforts to consolidate the radioactive waste of one nuclear power plant in a safe manner will require investments of energy, materials and economic power of the same order of magnitude as the investments during the operational lifetime of the reactor. After closedown of a nuclear power plants a massive energy debt is left to society, increasing over time due to the unavoidable deterioration of the temporary storage facilities and increasing leaks.This debt cannot be written off as incollectable, like a financial debt, because the health of millions of people is at stake. If it goes wrong with the radioactive heritage of a nuclear power plant – and it will go wrong if nothing is done – it will go terribly wrong. We just cannot move millions of people to another, not contaminated region. Obviously the economy will also suffer a heavy setback in case of a severe accident. The chance of such accidents increse with time.

Nuclearpowerdeliversenergyoncredit. Privatizingprofits,socializingcosts.

Paradigm barrier

The barrier blocking the way to a sound completion of the nuclear chain is a paradigmatic one, the present state of technology is amply adequate. Main elements of that paradigm are:• Short-term profit seeking• Living on credit• Aprèsnousledéluge attitude• Belief in concepts only possible in cyberspace.

Economic challenge

The monetary debt ensuing from the energy debt and material debt has a character completely different from the monetary debts economists are used to. Present economic concepts are invalid to handle the problems and risks posed by the nuclear heritage, in view of the following characteristics:• Energy is a conserved quantity. The energy debt is not discountable and cannot be written

off as uncollectable. • Energy units do not depend on place and time, nor on politics, nor on economic concepts.• The size of the energy debt is of unprecedented size in history. Each nuclear power plant

leaves behind an energy debt as large as about one third of its lifetime energy production. During the next decades this debt fraction will rise considerably, as result of the decline of

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the quality of the required nuclear-related mineral resources.• The timescale of the tail of the nuclear chain, over a 100 years, is unprecedented in history.• The massive investments of energy, materials and human resources do not contribute to the

improvement of the economic infrastructure and must be considered to be pure losses. As the investments are used to isolate the radioactive wastes including their packing from the human environment, they will vanish from the economic system forever.

• The energy debt is not subject to monetary-like depreciation, on the contrary, it will increase with time, for reason of inevitably deteriorating materials and constructions, following from the Second Law. The longer the adequate actions will be postponed, the more energy, high-quality materials and economic effort will be required to achieve a given level of safety.

Any country with an appreciable number of nuclear power plants, such as France, Great Brittain and the United States, should reckon on economic efforts of Apollo project size, many hundreds of billions of euros, to keep their territory (and of the neighbour countries) habitable. Would the decision makers foster such efforts, or does the world need another Chernobyl or Fukushima disaster? The current way of economic thinking, pursuing only short-term profit goals, is not reassuring.

With respect to radioactive waste problems and health risks the nuclear world seems to foster a culture of downplaying and concealing risks and of an unrealistic belief in unproved and unfeasible technical concepts, exacerbated by an attitude of postponement which may be best described as an aprèsnousledéluge attitude.Usually this attitude is based on questionable arguments and fallacies, such as:

‘Technology advances with time and future generations will be richer than our generation, so they

will have more economic means and better technological possibilities at their disposal to handle the

waste problem.’

A dangerous misconception

The view that the solution of the radioactive waste problem is just a matter of advanced technology is a misconception, for the immobilization of radioactivity is a Second Law problem. It will not be possible to prevent the spread and dispersion of radioactivity into the environment by less effort than it would require at this moment by use of advanced, yet to be developed, technology. Spread can only be limited by dedicated human efforts, involving massive amounts of useful energy and materials. As useful energy and materials are becoming increasingly energy-intensive with time, the chances of solving the radioactive waste problem adequately can only decline with time.

Energy is the limiting factor

Scarcity of materials and energy is a thermodynamic notion, in the long run not economic scarcity counts, for energy is the limiting factor of all economic activities. Ultimately the quality and usefulness of natural resources is determined by the consumption of useful energy and ordered materials required to recover one unit raw material from the crust. Useful energy from mineral energy resources (fossil fuels and uranium) is requiring increasingly more investments of energy and materials per unit useful energy as the easy resources are getting depleted. Materials, such as copper, are becoming increasingly more energy-intensive, as the high-quality resources (high grades, low depth, easy accessible) are getting exhausted. Both trends reinforce each other.

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uranium ore

front endprocesses

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cooking the meal enjoying the meal the dishes and mess are piling up

Figure 16-1. The nuclear process chain as it turns out to be, with paradigm barrier.The radioactive wastes from 60 years nuclear fission technology is piling up in the world, creating an ever

growing energy debt. All wastes are still to be isolated from the human environment.

40 100

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ive

gros

s ene

rgy

prod

uctio

n

startup

buildup energy debt

closedown

spentduringlifetime

Figure 16-2. The energy debt of the nuclear energy system.After closedown of the reactor a large energy debt has to be paid off, in order to safely isolate the

radioactive wastes from the human environment. The energy debt increases with time for two reasons:

first, the radioactive materials are getting increasingy dispersed due to deterioration of the containing

materials and structures with time, secondly the materials needed for packing the radioactive waste will

become increasingly energy-intensive.

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i17

Dispersion of radioactivity

Pathways

Assessment of the complex of industrial activities related to nuclear power [more i12] reveals a number of pathways along which hazardous radioactive materials can enter. and are entering, the human environment. Like any industrial system the nuclear process chain is leaking fractions of its contents into the environment. Some discharges are unintentional, some intentional for economic reasons and some by accidents.Appraising these pathways of radioactivity entering the human environment, the conclusion must be: Nuclearpowerisinherentlyunsafe.

Routine releases

Authorized intentional releases: routine discharges from nuclear power plants, reprocessing plants and other nuclear installations. On daily base these releases may not seem significant, but because they are going on day after day, year after year, considerable amounts of radioactive materials are cumulating in the environment [more i19].

Unauthorized releases

Unauthorized and often unnoticed releases, caused by leaks, sloppy maintenance and/or small-scale accidents, often combined with the insufficient possibilities of detection of many kinds of radioactive materials. These kind of releases are occurring frequently.

Uranium mining

Radioactive dust and groundwater contamination by uranium mining. The mining wastes from mining contain a number of different dangerious radionuclides, among other polonium-210, which are physically and chemically mobilized. Most uranium mines are situated in arid regions. The radioactive dust from uranium mines is blown by the wind over very large distances: hundreds of thousands of square kilometers are contaminated in this way. The groundwater table is contaminated with chemically mobile radionuclides, but also with non-radioactive chemical contaminants, such as arsenicum [more i18].

Depleted uranium

In the enrichment process natural uranium, with a fissile U-235 content of 0.71%, is separated into two fractions: a small mass fraction of enriched uranium, containing 2-5% U-235, and a larger mass fraction of depleted uranium, containing 0.2 - 0.3% U-235. For each kilogram of enriched uranium 6-7 kg depleted uranium (DU) are left. Depleted uranium is stored as uranium hexafluoride, the chemical form needed in the enrichment process, in steel vessels lined up in sheds or in the open air. World-wide more than a million tonnes of depleted uranium are stored,

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an amount growing each year by some 50000 Mg.

During storage the radioactivity of depleted uranium steadily increases due to cumulation of radioactive decay products of U-238 and remaining U-235. Uranium hexafluoride is chemically a reactive compound, easily reacting with water and moist air. All uranium compounds are highly toxic: in addition to its chemical toxicity, comparable with lead, uranium is a dangerous alpha emitter. The element tends to cumulate in bones and kidneys.

Health risks posed by depleted uranium are threatening when the uranium hexafluoride containers go leaking. This is happening at an increasing rate as result of the unavoidable deterioration of the containers, to corrosion and other causes.

Illegal trade and criminality

Illegal trade, smuggling and criminality involving radioactive materials of often unknown activity and composition. Detection of radioactive scrap is troublesome and can easily be disguised. Nuclear-related materials are often of high value on the free market.The nuclear industry uses large masses of expensive high-grade metals, alloys and other materials. After replacement of equipment or dismantling of nuclear facilities these materials may enter the market as used materials. Who controls the sorting of radioactive from non-radioactive scrap? Who safeguards the batches of high-value scrap which are not released for free use? Illegal trade, smuggling and criminality are already worrisome at this moment. Too often pulses of radioactivity are observed in the flue gases of metal smelters and recycling plants of special materials.

Radioactive scrap and metal components can be smuggled out of a port or country relatively easily. Detectors, if present at all, have limited detection possibilities. Detection of many radionuclides in scrap metal or concrete rubble is very difficult if alpha emitters (uranium and transuranics) or low-energy beta-emitters (e.g, tritium and carbon-14) are involved; low-energy gamma emitters may escape detection as well. The absence of easily detectable radionuclides, such as the gamma-emitting radionuclides cesium-137 and cobalt-60, in no way warrants the absence of other dangerous radionuclides. So, when scrap metal or rubble is cleared for unrestricted use after superficial screening with a radiation detector, how sure we are wether all nuclides present in the materials have been measured and accounted for? Or, are the clearance standards based on just a few easily detectable nuclides?Besides, it is relatively easy to shield radiation sources in a container from detection by non-radioactive scrap. In addition the human factor may play a part. How reliable are the inspectors?

Up until 1993 large amounts of radioactive waste has been dumped at sea, including discarded ship reactors. A 1993 amendment to the London Dumping Convention halted the ocean disposal of all radioactive waste. From 1979 on ships loaded with wastes have been wrecked under questionable circumstances in the Mediterranean at an increasing rate, 20 of these wrecks are considered extremely suspicious with regard to radioactive waste. Serious engagement by magistrates and politicians to investigate the wrecks and their cargo has been lacking. How is the situation elsewhere at the world’s seas?

Transport

The various processes of the nuclear chain are at widely spaced locations, often on different continents. Nuclear power involves many transports over long distances, up to tens of thousands kilometers. Particularly the transport of spent nuclear fuel and vitrified waste after reprocessing

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involves large amounts of radioactivity. Every transport of nuclear material enhances the risk of dispersion of radioactive material into the biosphere.

Cleanup, decommissioning and dismantling of nuclear plants

Each nuclear power plant has to be decommissioned and dismantled after closedown. The main part of the buildings and equipment (e.g. turbines and generators) are not radioactive, if the plant has operated nominally during its technical life. The reactor vessel and associated equipment, piping, pumps, etcetera, have become highly radioactive as a result of neutron radiation and contamination with radioactive materials. Restoration of the site of a given nuclear power plant to habitable greenfield conditions again requires a sequence of very costly activities over a period of a 100 years or even more [more i20].

Terrorism

Increasing amounts of mobile radioactive materials also increase the chances of malicious spread of radioactivity into the environment. Matter of concern are, among other:• MOX fuel• dirty bomb• attacks on nuclear power plants and vulnerable facilities with large radioactive inventories, such as spent fuel storage facilities and reprocessing plants.

MOX is the acronym of Mixed OXide fuel, nuclear fuel with plutonium instead of U-235. MOX fuel is relatively little radioactive and can be handled without specialized equipment by people who don’t care about their health. The fuel can be separated into uranium and plutonium using simple chemical techniques every chemistry student knows. The so-called reactor-grade plutonium from the MOX fuel can be used in a crude nuclear bomb, despite its less than optimal isotopic composition. Such a bomb might be not very reliable, and its explosive yield might be relatively low, but these drawbacks might be irrelevant to suicide terrorists planning an attack in the center of a large town. This is the reason why so many scientists all over the world are strongly opposing reprocessing of spent fuel and the use of MOX fuel in civilian reactors.A dirty bomb is understood to be a conventional explosive used to disperse an amount of any hazardous radioactive material.

Armed conflicts

An armed conflict with convential weapons has the potential to cause severe nuclear accidents, if nuclear power plants or storage facilities are hit by bombs and/or penetrating projectiles, intentionally or by accident. Although storage facilities are safeguarded, all are vulnerable to wartime activities. Even nuclear power plants with heavy containment buildings are not able to withstand attacks with conventional weapons.

A forced shutdown of nuclear power plants of the adversary of a belligerent party may be an attractive option. Nuclear power plants are generally large units, 1000-1600 MW, and by cutting out one or more of these large units the energy supply of the adversary, and with it its economy, is dealt a heavy blow.

Armed conflicts may seem a remote possibility in Western Europe and in the USA, but how about other nuclear countries in the world? The consequences of a severe nuclear accident do not stop at our borders. Chernobyl proved how far-reaching those consequences can be.

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Severe accidents

Severe accidents cause releases of massive amounts of radioactive materials over vast areas. Severe accidents are possible at places where large amounts of radioactivity are present in combination with potential mechanisms of uncontrolled disperal: nuclear reactors, spent fuel storage pools, storage tanks with wastes at reprocessing plants [more i21].

uraniumore

upstreamprocesses

interimstorage

© Storm

Figure 17-1. Radioactivity in the nuclear process chainThe nuclear process chain mobilizes natural radioactivity and generates a billion imes more man-made

radioactivity. The chain is still open-ended: all radioactivity ever generated is still in mobile condition

within the human environment. Unavoidably significant amounts of radioactivity are dispersing into the

air, water and soil.

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i18

Uranium mining

Radioactive decay products

Uranium is a radioactive metal, which decays by alpha and gamma emission into other elements, called the decay products or ‘daughters’. The decay products are also radioactive, most of which are potent alpha-emitters. Consequently uranium bearing rock contains a number of radioactive elements. In the natural condition the radionuclides are confined in more or less insoluble minerals in the rock of the uranium ore deposit. Uranium ores are generally very old geologic formations, with ages of 1-2 billion years. In spite of its old age uranium-bearing rock is anything but harmless, for the rock emits gamma radiation and the dust of it contains dangerous alpha emitters. By far the most uranium deposits of the world are located in sparsely inhabitated and often arid regions, for example in Australia, Namibia, Kazakhstan and in the USA.

Mill tailings

To obtain uranium it has be extracted from uranium ore by physical and chemical separation processes. At the uranium mine the ore is mined, then milled (ground to powder) and finally chemically treated to extract the uranium. The other radionuclides in the ore, the decay products of uranium, remain in the tailings (waste stream) of the extraction process. The mill tailings have the appearance of a watery mud and consist of the ore powder, chemicals and large volumes of water. The radioactive mud is stored in large ponds. From then on the radioactivity from the uranium ore is mobile.A part of the water from the mud will evaporate and the other part, including the dissolved radionuclides, drains into the ground. When the mill tailings go dry, the remaining fine powder will be easily spread by the wind. This situation occurs when one pond is filled up and a new one is taken into operation and after the mine has been mined out and is abandoned.

Satellite photographs show dust from the Sahara desert crossing the Atlantic Ocean under certain conditions. An indication how far dust, and so radioactive dust, can be transported by the wind. Hundreds of thousands of square kilometers are contaminated in this way. The dust blown off the mill tailings contains highly radiotoxic elements, such as Ra-226, Pb-210 and Po-210. The lethal dose of polonium-210 is some 50 nanogram. Inhalation of the dust is a dangerous contamination pathway, for most of the radionuclides are potent alpha emitters. The decay products can also enter the body via drinking water, as the groundwater at large distances from the mining area may be contaminated with soluble compounds of the radionuclides, seeping from the mill tailings. The groundwater table in vast areas is also being contaminated with non-radioactive chemicals, such as arsenicum.

Mine reclamation

Mine reclamation (also called rehabilitation) comprises the actions needed to restore the mining area to a habitable one again. The chemically mobile radionuclides in the mill tailings

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should be immobilized again and put back in the mining pit, as deep as possible. To prevent remobilization by groundwater flows, the mill tailings must be shielded from the groundwater by an effective barrier, for example thick layers of bentonite. Bentonite is a clay mineral with special properties: it swells by the uptake of water, effectively closing fissures and microchannels, and has strong ion-exchange properties, resulting in a very low migration rate of nuclides, other than hydrogen ions and some alkali metal ions.

Nowhere in the world, as far as known, has the impact on the environment by uranium mining been compensated for in a way that can be considered ecologically adequate and safe to the local inhabitants. Uranium mining companies leave the mill tailings unshielded in the mining area. After the last kilogram of uranium has been removed from the site, the lights are turned off and the gate is closed.

Figure 18-1. Satellite photo of the Ranger uranium mine in AustraliaSatellite photo of the Ranger uranium mine in Australia, a medium-sized and one of the cheapest operating

uranium mines in the world. The large green geometric pond on the lower left is the mill tailings pond.

The light colored areas are the overburden and waste rock dumps. The active mining pit is the one at the

upper right, partially flooded. The round dark object at the lower center is a former, mined out, pit which

is fully flooded. The extraction plant (mill) is on the far right, barely discernable. Note the scale bar in

the lower left corner. Source photo: Google Maps.

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uranium oxidechemicals water

uranium ore

uranium ore deposits

bentonite

Rn-222

Rn-222

mill

pristine

mining, current practice

immobilized waste (future?)

mill tailings

mill tailings + immobilizing chemicals

overburden& waste rock

overburden& waste rock

© Storm

© Storm

Figure 18-2. Uranium mining and mine reclamationOutline of uranium mining, the first step of the nuclear process chain. The area directly disturbed by

the mining operations of a large uranium mine may come to some 100 km2. The indirectly disturbed

area, by wind blown dust and contaminated groundwater, may run into hundreds of thousands of square

kilometers. When the ore is exhausted, the dangerous mill tailings should be immobilized and the mine

and its surrounding area should be restored to the original situation, a process called mine reclamation.

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Figure 18-3 Dust storm from the Sahara into the Atlantic.A massive sandstorm blowing off the Northwest African desert has blanketed hundreds of thousands square

kilometers of the Eastern Atlantic Ocean with a dense cloud of Saharan sand. This photo shows how far

dust from arid areas, including radioactive dust from uranium mines, can be transported by the wind.

Photo SeaWIFS/NASA.

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Routine releases of radioactivity

Significance

Routine releases are the authorized intentional discharges ofradioactive effluents from nuclear power plants, reprocessing plants and other nuclear installations. On daily base these releases may not seem significant, but because they are going on day after day, year after year, considerable amounts of radioactive materials are cumulating in the environment. As far as known no systematic investigations have been performed on the health effects of the cumulation of radioactivity by routine releases in the human environment. Recent reports in Germany and France proved that routine releases are far from harmless [more i23].

Discharges from reactors

During the fission process in the nuclear reactor tens of different kinds of radionuclides come into being in the fuel, in the coolant and in the construction materials. Operating reactors release in the liquid and gaseous effluents some fission products and activation products, such as tritium, carbon-14, noble gases (mainly krypton-85) and iodine-129. The fission products originate from leaking fuel pins and uranium contamination on the outside of the pins. The activation products are produced by neutron reactions on light elements in the cooling water and on corrosion products.Data on operational discharges of nuclear power plants are scarce and incomplete; extremely little direct measurements have been published.Some small quantities of iodine-129 are undoubtedly present in gaseous and liquid effluents from power reactors, but it measurement is difficult because of high concentrations of other fission and activation products.

Interim storage of spent fuel

After removal from the reactor spent fuel elements have to be stored in water-filled cooling ponds for a long period, this is called interim storage. Due to the radioactive decay of the fission products and actinides the spent fuel generates so much heat, that fuel elements will melt within a short time if not effectively cooled. After some 30 years interim storage in cooling ponds the heat production has decayed sufficiently to handle the fuel elements for further processing.Interim storage may become a source of inadvertent emission of radioactivity. During the storage 80-90% of the tritium in the fuel will diffuse from the fuel and released into the environment. Other nuclides are released into the cooling water from leaking fuel pins. The number of leaks will rise over time, due to ageing, corrosion and deterioration of the materials.

Operation and maintenance of the interim storage facilities are expensive. The water in the pools has to be actively cooled and decontaminated during een period of at least 30 years. The spent fuel of the new generation of reactors, such as the EPR, has to be cooled for a period of at least 60 years. The basins deteriorate and may go leaking, as happened at several occasions

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in the past, and have to be replaced. These activities do not generate financial profits for the company which operated the nuclear power plant during its productive life. Does that company still exist 30-60 years after closedown of the plant?

Reprocessing plants

Reprocessing plants discharge large quantities of radioactive materials into the environment. All gaseous fission and activation products from the processed spent fuel are routinely released into the atmosphere: radioactive noble gases krypton and xenon, tritium, carbon-14 and iodine. Substantial amounts of chemically mobile radionuclides, which do not easily form stable and/or insoluble compounds are discharged into the sea via the waste water streams. As separation processes never go to completion, significant amounts of actinides are released, in addition to the discharged soluble or gaseous fission products [more i31]. The standards of permitted releases, which are formulated by the nuclear industry, are dimensioned in such way that the reprocessing plants are permitted to discharge into the environment all radionuclides which are difficult to retain.

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Cleanup, decommissioning and dismantling

Radioactive structures after closedown

Each nuclear power plant has to be decommisioned and dismantled after closedown. The main part of the buildings and equipment (e.g. turbines and generators) are not radioactive, if the plant has operated nominally during its technical life. The reactor vessel and associated equipment, piping, pumps, etcetera, have become highly radioactive as a result of neutron radiation and contamination with radioactive materials (CRUD: corrosion residuals and unidentified deposits). Restoration of the site of a given nuclear power plant to habitable greenfield conditions again requires a sequence of very costly activities over a period of a 100 years or even more.

Other nuclear facilities are also to be dismantled at a given time. Due to ageing, cracking, wear, corrosion and other deteriorating mechanisms any facility processing radioactive material will become increasingly contaminated with radioactive material. When the radiation doses for the personel become irresponsible or when the safety is at issue as a result of unreliable equipment, a nuclear plant has to be closed down.

Nuclear power plants

The activities related to the decommissioning and dismantling of a nuclear power plant can be divided into four stages, known under different names in the literature:• plant cleanout, decontamination or decommissioning• safe-guarded cooling period, safe enclosure or ‘safestor’• dismantling, demolition of the structures• site clearance, including packing of the debris and scrap, • definitive storage of the waste containers in a repository.

The radioactive inventory of the reactor with connected systems and shielding materials increases with operational lifetime of the reactor, by activation reactions, depending on the neutron flux. Based on model computations the radioactive inventory of a light-water reactor (LWR) after 20 full-power years is estimated at some 0.1 - 0.6 EBq (exabecquerel, 1 EBq = 1 billion times 1 billion radioactive desintegrations per second), one year after final shutdown, excluding the spent fuel and control rods.

The radioactive inventory also rises during the operational years by progressive contamination of the system, despite of chemical and mechanical decontaminating activities during operation of the reactor. Not only the radioactivity measured in becquerel units, but also the kind of the radionucli-des contaminating the system has consequences for the way of demolition and handling the wastes. With longer operating times, the chances on contamination with fission products and actinides increase.

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Reprocessing plants

Contamination is extensive in a reprocessing plant. Dismantling of the huge buildings will generate large volumes of heavily contaminated wastes. Costs will be high, because large parts of the construction are contaminated with dangerous long-living radio-nuclides and alpha-emitting wastes. Experiences with dismantling the West Valley reprocessing plant in the USA (a small plant which operated during the period 1966-1972) and some minor DOE plants, are not encouraging. Forty years after closedown the cleanup activities will still take at least another decade and investments of many billions of dollars. The final decommissioning and dismantling costs are estimates at 40 times (!) the construction cost of the West Valley plant.

Dismantling of a reprocessing plant will be an exceedingly demanding task. Reprocessing plants are among the largest industrial complexes in the world. The hot areas, the compartments in which radioactive materials are processed, are strongly contaminated with radionuclides representing almost the entire Periodic Table of the Elements, including the transuranic actinides. The volume and mass of the radioactive debris and scrap resulting from the dismantling of a reprocessing plant will be a multiple of those from a nuclear power plant.

Health risks

The radioactive structures of the nuclear power plants and reprocessing plants have to be cut in small pieces, packed in steel or concrete containers and definitively stored in a safe geologic repository. How much dust and leaked liquids containing radionuclides will be dispersed into the environment? Who controls which piece is not radioactive and which one is?The demolition debris contain large amounts of many different long-lived radionuclides and not all radionuclides are easily detectable. As pointed out before, there is no relationship between the biomedical activity of a radionuclide and its detectability by common radiation counters. As yet little actual measurements, if any, of the radioactive content of dismantling debris have been published.

The health risks of decommissioning and dismantling may seem remote, for they are not very visible at this moment. No commercial nuclear power plant nor any reprocessing plant has completed the dismantling sequence. By the year 2050 more than 500 nuclear reactors are awaiting the final cleanup. The large volumes of waste and the long lead times involved greatly enhance the chances of inadvertent releases of considerable amounts of radioactive materials into the environment.

Radioactive debris and scrap

Surges in illegal trade of radioactive scrap metal may be expected in the future when large nuclear power plants are dismantled, for massive amounts of high-value metals at various levels of radioactivity are released during dismantling. Preliminary estimates – empirical evidence is still not existent – point to the following figures of radioactive and contaminated materials for one 1 GWe nuclear power plant:• 1600 Mg (metric tonnes) of high-grade steel, stainless steel and special alloys• 10000 Mg steel• 500 Mg non-ferrous metals• 3000 Mg other materials • 30000 Mg concrete rubble.In addition some 5000 Mg decontamination waste is generated, which is highly radioactive and likely will have no commercial value.

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Regulations and economics

All these wastes have to packed in appropiate containers, which should be permanently stored in a geologic repository [more i11]. The high and continually rising costs of radioactive waste management may easily provoke undesirable and hazardous situations. Regulations are relaxed to admit higher concentrations of radioactiviy in materials from nuclear installations for clearance, for economic reasons [more i26, i27]. The IAEA proposes to dilute radioactive materials, such as scrap originating from dismantling nuclear-related installations, with non-radioactive materials, to be used for ‘special purposes’. This is a hazardous proposal for it is inherently uncontrollable.

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Severe accidents

Meltdown

Severe accidents, involving the uncontrolled release of large amounts of radioactivity, occur in case of the meltdown of a reactor core or of a spent fuel pool. When the cooling of a reactor or spent fuel pool fails, the fuel elements go heating up rapidly and will melt due to the residual heat of nuclear fuel. The hot zirconium hulls of the fuel elements react with water generating hydrogen. As the hydrogen gets mixed with air, the mixture will explode. This scenario happened at Chernobyl in 1986 and at Fukushima in 2011. As a result of the explosion a large part of the radioactive content of the reactor and/or spent fuel pool will be dispersed into the environment.

Spent fuel pools

Especially the spent fuel pools entail high risks because these contain usually the spent fuel of a number of years with a radioactivity of thousands of nuclear bomb equivalents. In addition the spent fuel pools are not situated in a heavy safety contaiment like the reactor. Meltdown of a reactor is highly hazardous, because the molten nuclear fuel may become easily critical again, starting an uncontrolled fission process generating more heat and radioactive fission products. The molten fuel in a boiled-dry fuel pool can also become critical, as happened at Fukushima.Scenarios are conceivable of explosions at spent fuel storage facilities with consequences that could dwarf the Chernobyl and Fukushima disasters. One operating reactor contains about 1000 bomb equivalents of radioactivity, some storage pools contain many tens of thousands of bomb equivalents.

Consequences

The consequences of a Chernobyl/Fukushima-like disaster are very serious. Large regions, tens of thousands of square kilometers, are so heavily contaminated with radioactive materials, that these areas become in fact inhabitable forever. Some kinds of radionuclides, with short half-lifes, will decay within weeks or months to ‘low’ levels, other will remain for thousands of years. Many kinds of dangerous radionuclides are difficult to detect and enter the food chain undetected.

Contamination

How are ‘low’ levels defined? Who determines how harmless a given ‘low’ radioactivity level is to people living in a contaminated region and who are chronically exposed to the radioactivity? Besides, several radionuclides tend to accumulate in living organisms, in food. So it can happen that the exposure to harmful radioactivity is far higher than predicted on base of the average contamination of an area. In addition a number of biologically active radionuclides are not easily detectable and generally are not monitored and are left out of consideration [more i24].

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Figure 21-1. Extent of a large-scale nuclear accidentThe spread of caesium-137 (Cs-137), a fission product, after the Chernobyl disaster in 1986. The darkest

colored areas have become in fact inhabitable due to radioactive contamination. In the blanc areas

insufficient data were available. The lightest colored areas did not get an appreciable radioactive

deposition. The spread of the many other radionuclides escaped from the exploded reactor is not

necessarily the same as that of cesium-137.

boiling-waterreactor(BWR)

containment

BWR Mark I

cooling pondwith spent nuclear fuel

Figure 21-2. Boiling water reactor.The spent fuel cooling basin of this type of reactors are outside of the containment structure around the

reactor, as is with all other types of nuclear power plants.

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Figure 21-3. Areas at risk in Europe.Chart with the nuclear power plants of Europe. The darkest colored areas are within 30 km of an NPP and

are the areas to be evacuated in case of an accident releasing nuclear fuel. The risks posed by accidents

involving the interim storage of spent fuel might be greater than reactor accidents. Most interim storage

facilities are located at the reactor sites.

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Figure 21-4. Spent fuel cooling basin at a reprocessing plant in the UKThe blue light is the result of the interaction of the radiation of the fuel elements with the cooling water.

The cooling ponds of nuclear power stations are smaller than this one, but of the same design.

Figure 21-5. Explosion of a spent fuel cooling basin.Explosion of the spent fuel cooling basin of reactor 3 at the Fukushima Daiichi plant on March 14, 2011.

As a result of the breakdown of the cooling of the basin, the spent fuel partially melted and reacted with

the remaining water. The hydrogen generated by this reaction exploded, initiating a criticality incident in

the (partially) molten nuclear fuel.

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i22

Health effects of radioactivity in the human body

Stochastic and non-stochastic effects

There are stochastic and non-stochastic effects of nuclear radiation. Non-stochastic effects occur at very high doses within a short period and are due to cell killing on a massive scale. The effects become evident within hours or days. Demonstrable relationships exist between the effects and the magnitude of the received radiation dose. Non-stochastic effects are important in case of nuclear explosions and large nuclear accidents, typically during nuclear conflicts.

Stochastic effects occur at random and at lower radiation doses. The effects become evident only after months or ywears or even decades. The classical radiobiology assumes a linear relationship between dose and adverse effects. However it not certain if an individual will develop a cancer or other adverse effect. If a large number of individuals receive the same dose, one can predict the number of individuals who will develop an adverse effect, but not which individuals. With regard to stochastic effects there is no threshold of the received dose below which adverse effects certainly will not occur.

Targeted, non-targeted and delayed effects

The classical explanation for stochastic radiation health effects was that they were mostly caused by structural DNA damage (i.e.single- and double-strand DNA breaks) which resulted in mutations in the cell’s genetic information that, without repair or elimination, would end eventually in cancers. This is the target theory of radiation effects, the target being specific sequences in DNA and chromosomes.

Relatively recent studies proved the existence of ‘non-targeted’ and ‘delayed’ radiation effects. Probably these effects had been observed in earlier studies but they had been unrecognised as they fell outside the then accepted paradigm of radiation effects. Non-targeted effects, which arise as a result of damage/changes to unknown areas in the cell, are termed ‘non-targeted’ because they mainly do not cause damage/changes to DNA or chromosomes, heretofore believed to be the main site for radiation’s lesions. Non-targeted effects include:• genomic instability, • bystander effects (effects in unirradiated cells situated close to irradiated cells), • clastogenic effects (causing chromosome disruption or breakages in blood plasma that result in chromosome damage in non-irradiated cells),• heritable effects of parental irradiation that occur in succeeding generations.

Presently there is no mechanical explanation for how the non-targeted effects actually occur. The observed phenomena pose many fundamental questions to be answered and result in a paradigm shift in the understanding of radiation biology. Evidently the relationship between dose and adverse effects is not linear.

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Biochemical aspects of radioactivity

The standards for the public exposure to nuclear radiation were (and probably still are) based on the experience with diagnostic X-rays and gamma rays from external sources and originate from the early 1950s. Not included in the early models are the fact that the adverse effect of radiation is tens to hundreds of times more serious for the developing infant in the mother’s womb and for young childern than for the adults who have been studied following medical X-ray exposures.Not until the early 1970s it was discovered that the effects of prolonged low radiation expo-sures, as from long-lived radionuclides accumulating in the body, is much greater than from the same total dose received in a short X-ray exposure.

Some radionuclides have a specific biological behaviour and tend to accumulate in a special organ or tissue. In that case, the radioactivity is not evenly distributed among the body and doubling of the radioactivity of the body as a whole, means locally a sharp increase in radia-tion. The chemical properties of an element are not affected by the radioactivity of its atoms. For example, the biochemical machinery of the human body cannot distinguish between a normal water molecule or a water molecule with one or two radioactive tritium atoms.

High concentrations of a specific radionuclide in a specific organ are possible as a consequence of its biochemical properties. Radioactive iodine atoms for example, seek out the thyroid gland, together with its non-radioactive sister atoms, and damage the production of key growth hormones and cause thyroid cancer. Strontium-90 and plutonium tend to cumulate in the bones, where they irradiate the bone marrow, causing leukemia in newly forming red blood cells as well as damage to crucial white cells of the immune system, with all consequences of that. Cesium-137 collects in soft tissue organs, such as the breasts an reproductive organs of females and males, leading to various types of cancer in the individuals and their childern as well as in later generations.

Radiation-induced diseases

In the regions contaminated with radioactivity after the Chernobyl disaster a greatly increased incidence of a many different maligne and non-maligne diseases and disorders are observed, such as:

multimorbity classified as radiation-induced premature senescence, cancers and leukaemiathyroid cancer and other thyroid diseasesdamage to nervous system, mental disordersheart and circulatory diseasesinfant mortalitycongenital malformationsendocrinal and metabolic illnessesdiabetesmiscarriages and pregnancy terminationsgenetic damage, hereditary disorders and diseasesteratogenic damage, such as: anencephaly, open spine, cleft lip/palette, polydactylia, muscular atrophy of limbs, Down’s syndrome

In some areas in Belarus and Ukraine nearly all habitants are suffering from one or more radiation-induced diseases.

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Downplaying the hazards

Long time lag

Quantification of the relationship between exposure to radioactivity and the (allways adverse) effects is problemic. Usually it is hardly possible to prove unambiguously the relationship between a once contracted dose of radiation with an individual and carcinogenic, mutagenic and teratogenic effects, for several reasons:• long incubation periods, months to years or decades• stochastic character of the biological effects• basic biomedical unknowns.The long time lag between exposure and observable health effects – for example the heritable damage to egg cells in young women may only become evident after some 30 years – forces the medical sciences to employ special methods to assess the hazards of nuclear power.

Downplay

The long time delay gives the nuclear industry the opportunity to downplay the effects and even to deny in many cases that radioactivity caused the observed adverse health effects. Other factors are blamed to be the cause of observed disorders, sometimes even psychosomatic factors: ‘radiophobia’, the angst of radiation. Of course assertions of this kind come from people living far from radioactive-contaminated areas.

From a purely scientific point of view above assertions are fundamentally flawed. When it is not possible to unambiguously prove that radioactivity is the cause of the adverse health effects observed at a given time in a given region, then you have to prove that radioactivity cannot be the cause. Just on base of such a falsification procedure one may assert that radioactivity is not the cause but other factors are.

For decades the International Atomic Energy Agency (IAEA), World Health Organization (WHO) and the nuclear industry claimed that the death toll of the disaster at Chernobyl was 31, later rised to 64. Apparently only the victims of non-stochastic effects, who died within days, have been counted. The death toll world wide of the Chernobyl disaster is estimated at nearly one million people, based on publications from Russia, Belarus and Ukraine, which the IAEA and WHO did not study. In addition to these victims there are innumerable people with incurable diseases and malformations following the disaster in 1986.

At present the nuclear industry is strongly downplaying the gravity of the Fukushima disaster, which is classified as ‘non-catastrophic’. The worst effects in the industrial view are economic losses and less support for new nuclear power stations.

Reliable investigation of the effects of radioactivity in the human evironment needs the registration of cases over a long time span. By means of epidemiological studies an independent

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assessment of the consequences of exposure, especially chronic exposure, to radioactivity is possible. Unfortunately such registrations usually remain undone, intentionally or for economic reasons.

Epidemiological studies are also needed to analyse the effects of permanent exposure to low doses of radionuclides via water and food in contaminated areas, not only after a large accident, but also near nominally operating nuclear power plants en reprocessing plants.

Evidence

Major independent epidemiological studies in Germany and France found a strong connection of the incidence of cancers with young childern and the proximity of their living location to nominally functioning nuclear power plants. The existing models of dose-effect relationships cannot explain the results of these studies.

The IAEA, WHO, UNSCEAR and nuclear industry [more i01] are now playing down the consequences of the Fukushima disaster of people living in the contaminated regions. Assertions as “no casualities”, “no ill effects” or “no ill effects expected” are seriously misleading, if not untruthful, because they are not underpinned by an elaborate and independent epidemiological investigation among the affected people. Such an investigation should be continued for many years, for reason of the long incubation times of diseases caused by exposure to radionulides.

Future investigations of the health effects with the involved people are seriously hampered by the fact that systematic and relevant measurements of contamination by different kinds of radionuclides are left undone. All biologically active radionuclides should be monitored, such as tritium, carbon-14 and the actinides, not just cesium-137.

Health risks resulting from downplaying

The habit of the nuclear industry to downplay health hazards posed by radioactivity in the human environment greatly enhance the health risks the public is exposed to, not only in case of accidents, but also during nominal operation of nuclear installations.Necessary measurements may remain undone, measures to avert avoidable esposures may be left undone.

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i24

Limited knowledge on radioactivity

Not all radioactivity is measured

Nuclear power is inseparably coupled to the generation of large amounts of man-made radioactivity, distributed over dozens of different radionuclides (radioactive isotopes of the chemical elements). Each radionuclide has its own physical and chemical properties and biological behavior.

Unavoidably a substantial part of the man-made radioactivity escapes into the environment, partly by authorized routine releases, partly by leaks and small accidents, and partly by large disasters, such as Chernobyl and Fukushima. Via these pathways all kinds of radionuclides are released into the human environment [more i17]. A part of the radionuclides are dispersed in gaseous form, another part as aerosols, a third kind solved in water. The radionuclides are entering the food chain and drinking water supply. A number of kinds of radionuclides tend to accumulate in living organisms, locally resulting in high radioactivity. Some kinds of radionuclides are biologically very active in the human body, such as tritium (radioactive hydrogen, symbol T or H-3), carbon-14 (radioactive carbon, symbol C-14) and radioactive iodine (symbols I-129 and I-131).

Troublesome detection of radioactivity

The presence of radionuclides is not always easily detectable. Several radionuclides, including tritium and carbon-14, cannot be detected by handheld detectors. Some dangerous alpha emitters, such as plutonium, are also difficult to detect, the more so in the presence of strong gamma emitting radioaclides. All these difficult radionuclides require special equipment.Radiometric surveillance after a severe accident such as Chernobyl and Fukushima focuses on the detection of cesium-137, an easily detectable radionuclide. From the measured intensity of gamma rays emitted by cesium-137 a dose rate (usually measured in millisieverts per unit time) is deduced: the amount of radiation absorbed per unit time by an individu at that location.

Apparently the nuclear industry assumes that the concentration of cesium-137 at a given location is a good measure of the health risks of the local people. This simplification ignores two important issues:• Due to their very different physical and chemical properties , the dispersion of the various radionuclides during and after an accident is widely different. Absence, or near-absence of cesium-137 does not warrant the absence of other, probably more dangerous radionuclides in soil, water and air.• Even if the dispersion of cesium-137 would be a good criterion for the dispersion of other radionuclides, then the simplification ignores the different pathways of radionuclides into the body (inhalation of gases and aerosols, ingestion via food and/or water) and the widely different biological activities of the various kinds of radionuclides in the human body.

By not monitoring continually the presence of a number of dangerous radionuclides in food,

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water and air, including the difficult ones, a false sense of safety could be roused. Necessary actions might remain undone, causing avoidable harm to people.Another serious consequence of the absence of monitoring is the fact that no data are collected for future epidemiological studies. In this way it becomes impossible to prove unambiguously the adverse health effects of a nuclear accident. The nuclear world then can keep playing down the health effects of a given accident.

Nomeasurements,noknowledge.

Biomedical unknowns

A number of radionuclides has been investigated to some extent, other nuclides (e.g. car-bon-14) practically not. The empirical database on effects of radonuclides in the human body seems to be very meager. Synergistic effects are unknown basically. What are the effects of several radionuclides together in a biological system?

The classical explanation for radiation’s effects was that they were mostly caused by structural DNA damage which resulted in mutations in the cell’s genetic information that, without repair or elimination, would end eventually in cancers. This is the target theory of radiation effects, the target being specific sequences in DNA and chromosomes. The doses causing non-targeted effects are too low to cause structural DNA damage. The dose-response curve of these effects is often not linear, with substantial increases at very low doses followed by a levelling off at higher doses. Presently there is no mechanical explanation for how the non-targeted effects actually occur. The target for radiation damage is greater than the initial tissue volume irradiated [more i22].The observed phenomena pose many fundamental questions to be answered and result in a paradigm shift in the understanding of radiation biology.

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i25

Health risks of nuclear power

Reliance on models

The official radiation dose-effect standards are based on a sequence of (old) models, which are hard to understand, even for scientists, and are based on a number of more or less arbitrary assumptions. The estimates resulting from these models have a large uncertainty range. Any model has its limitations and if one model generates the input for a subsequent model the uncertainties may cumulate considerably. The official standards do not cover mechanisms of biochemically active radionuclides emitting soft or no gamma radiation, which enter the human body by inhalation of gases and/or dust, or by ingesting via drinking water and food, and do not incorporate insights and evidence from the last decades.

What was the original purpose of the exposure and dose-effect models? To estimate the acute radiological risks for military personel in wartime, or to estimate the health risks for the public chronically exposed to radioactivity from civilian nuclear power? Health risk estimates should be based on published and verfiable scientific evidence, not on computer models originating from the closed nuclear world and based on secret data. Independent epidemiological studies proved the official models to be unable to explain the observed results.

History shows that the official standards for allowable doses and radioactive content of drinking water and food can easily be relaxed under economic pressure, recently during the aftermath of the Fukushima disaster. These relaxations were not based on sound scientific evidence, but were established merely for economic reasons [more i26].

Pathways of radioactive discharges

Hazardous radioactive materials can enter (and are entering) the environment via many pathways [more i16 ##]:• Authorized intentional releases • Unauthorized and often unnoticed releases, small-scale accidents• Illegal trade, smuggling and criminality involving radioactive materials.• Transport of radioactive materials• Terrorism• Armed conflicts, also with conventional weapons• Severe accidents.

The probability of unauthorized releases of radioactive materials and severe accidents grows with time, due to the ever increasing amounts of man-made radioactivity and the progressive ageing and unavoidable deterioration of the storage facilities and shielding materials of spent fuel and other radioactive wastes. The laws of nature are relentless.

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Risk enhancing factors

In addition to the probability of random technical failures of nuclear-related installations, there are a number of risk-enhancing factors, such as:• Human factor: sloppy maintenance, bad management, flawed problem identification and

resolution programs, shortages of qualified personel, violation of safety specifications, etcetera.

• Illegal trade, smuggling and criminality. Detection of radioactive scrap is troublesome and can easily be disguised. Nuclear-related materials are often of high value on the free market. With time the amounts of suspect materials on the market increases.

• Political instability may evoke terrorism and armed conflicts. Also a conflict with conventional weapons could cause large radioactive contamination if nuclear installations are involved.

• Questionable independency of inspections and safety control.• Insufficient possibilities of detection of dangerous radioactive materials.• Insufficient monitoring of food and drinking water on dangerous radionuclides, for example

tritium and carbon-14.• Insufficient knowledge of the chronic effects of permissable releases from nuclear power

plants and ,to a greater extent, the permissable releases from reprocessing plants.• False sense of safety – when people erroneously think radioactivity poses no danger – may

result in the omission of precautionary measures by authorities and individuals. A false feeling of no danger can result from the absence of adequate measurement and/or insufficient or even incorrect information, resulting from incompetence.

• The often long time lag between exposure to radioactivity and the first observable effects may also cause a false sense of safety.

• Downplay of the health risks by nuclear experts and/or authorities, for reason of financial and/or political interests.

• Creeping relaxation of the permissable exposure to radioactivity. A permissable standard defined as x units above ‘background level’ is not unambiguous: the background level rises when radioactivity is being released over longer periods, for instance by routine releases.

• Unprededictable natural events.• Economic considerations, forming a major risk factor [more i26].

Long time lag

Nuclear safety may easily become a seeming safety, due to the often long time lag (months, years, decades) between cause (inhalation or ingestion af radioactive material) and observable health effect [more i22]. This time lag gives the opportunity to downplay the dangers associated with radioactivity, unfortunately a common pheneomenon within the nuclear world. For that reason the time lag contributes to the unsafety of nuclear power.

Cumulation effects

The amounts of radioactive substances routinely discharged in a given year into the environment may perhaps seem relatively insignificant, however, year over year the released radionuclides can regionally build up to significant concentrations in groundwater and soil. Moreover a number of long-lived radionuclides accumulate in the food chain to high concentrations, even in a medium at very low concentrations of radionuclides (e.g. seawater). Cumulation of radionuclides into the food chain greatly amplifies the health risks of routine or accidental discharges of radionuclides. This mechanism is not addressed in detail in this study, to limit its scope.

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Health risks of nuclear power and economics

Inherently safe nuclear power is inherently impossible and there are no unambiguous nuclear health and safety standards possible based on unambiguous scientific and medical empirical evidence. This observation and the issues addressed in this study are pointing to the conclusion [more i14, i15, i26]:

Healthrisksofnuclearpowerareaneconomicallydefinednotion.

?

C14

142CO

OBC

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targeted, non-targeted & delayed effects

adverse health effects

DNAother biomolecules

HTOCOH14 3

–OBT

reactor

environment

HTO

T

Figure 25-1. Pathways of contamination with tritium and carbon-14.Pathways of radioactive hydrogen (tritium) and radioactive carbon-14 into the human metabolism.

Both radionuclides are routinely released into the environment by operating nuclear power plants. The

pathways are similar. It is generally assumed that damage to DNA molecules cause adverse health effects.

Cell damage turns out to be not limited to the cells directly hit by radiation, due to non-targeted effects

and the bystander effect. It is not known if and how radiation damage to other biomolecules could cause

adverse health effects.

T = tritium, HTO is radioactive tritiated water, OBT is organic bound tritium.14C = carbon-14, H14CO2

– = radioactive hydrogen carbonate dissolved in water, OBC = organic bound

carbon-14.

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i26

Economics and nuclear safety

Economic vs physical perpective

The economic perspective on nuclear power regards a limited part of the nuclear energy system and has a short time horizon of only a couple of years. For a nuclear economist a nuclear power project ends with the final shutdown of a nuclear power plant. To assess nuclear safety the complete system should taken into account, particularly the processes following the final shutdown, which might easily take a century [more i12]. In this respect economics and nuclear power are incompatible.

Liability policy

Most countries with nuclear power have an insurance policy for nuclear power stations providing equal liability protection regardless of risk (for instance the Price-Anderson Act in the USA). This kind of liability protection may be seen as a disincentive for safety, preventing safety upgrades from being incorporated into new reactor designs. An example of an economically optimized reactor design is Areva’s EPR (Evolved Pressurized-water Reactor), nevertheless now confronted with massive delays and cost overruns.

If handling and management of radioactive debris and scrap are left to private companies, profit seeking may prevail over safety and health risks. Short-term ‘solutions’ may be backed by financial constructions which leave the liability for failures and mishaps at the customer, in case the taxpayer. Such financial constructions seem to be involved in the contracts for decommissioning and dismantling the Sellafield reprocessing plant under authority of the British Nuclear Decommissioning Authority (NDA).

Responsibilities

The final cost of the complete sequence of spent fuel handling – interim storage, packing through definitive storage in a geologic repository – are unknown. A preliminary estimate of the lifetime cost may come to billions of euros per reactor.

The World Nuclear Association (WNA), presenting itself as representative of the nuclear industry, asserts:

“Nuclear power is the only large-scale energy-producing technology which takes full responsibility for

all its wastes and fully costs this into the product.”

This WNA statement is just short of a lie, in view of the facts and arguments presented in this series of Nuclearpowerinsights, and is also in conflict with the following remarks.• In the USA the federal administration is automatically responsible for the definitive storage of the spent fuel in a geological repository. Most likely the American taxpayer has also to pay for the decommissioning and dismantling of the nuclear power plants.• In the UK the closed down nuclear power plants are sold for a symbolic amount to the

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government, who gets the responsibility of the cleanup, decommissioning and dismantling of the discarded radioactive facilities. Most likely the British taxpayer has also to pay for the construction of a geologic repository plus the packaging and definitive storage of the nuclear waste.• In France a special situation is existing. All nuclear activities in France are managed by two state-owned companies: Areva and Electricité de France (EdF). Who pays the bill?

How is the situation in other countries, for example Russia, China, India, South Korea, Japan?

De-regulation

De-regulation (liberalisation) of the electricity markets has pushed nuclear utilities to decrease safety-related investments and limit staff.

Relaxation of activity standards

The high and continually rising costs of radioactive waste management may easily provoke undesirable and hazardous situations. Regulations are relaxed for economic reasons to admit higher concentrations of radioactiviy in materials from nuclear installations for clearance into the public domain. The IAEA proposes to dilute radioactive materials, such as scrap originating from dismantling nuclear-related installations, with non-radioactive materials, to be used for ‘special purposes’ [more i27]. This is a hazardous proposal for it is inherently uncontrollable.

The US Environmental Protection Agency (EPA) intends to raise the permissible levels of routine radioiactive emissions dramatically. The new standards permit public exposure to radioactivity levels in drinking water vastly higher than EPA had previously deemed unacceptably dangerous.EPA made not clear on base of what physical and medical evidence the standards could be relaxed.Other aspects of the EPA proposal are lax cleanups and higher exposures to other sources, such as relaxed dirty bomb standards.

Relaxation of exposure standards

Higher permissable concentrations of radioactive substances in drinking water, and consequently in food, inevitably cause higher individual exposures to radioactivity, resulting in more adverse health effects.In the aftermath of the Fukushima disaster the permissable dose for workers was at once raised fivefold for ‘emergency reasons’, without medical argumentation.

In view of the reliance on models within the nuclear industry and the ease to adapt models to changing needs of the nuclear industry, any relaxation of standards of permissable releases of and allowable exposure to radioactive materials should be based on solid verifiable physical and medical evidence.

Creeping relaxation of the permissable exposure to radioactivity. A permissable standard defined as x units above ‘background level’ is not unambiguous: the background level rises when radioactivity is being released over longer periods.

Relaxation of safety standards

A recent conflict between the chief of the US Nuclear Regulatory Commission (NRC) and the

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nuclear industry clearly demonstrates the tension between financial interests and nuclear safety. Efforts to tighten the safety standards for US reactors after the Fukushima disaster were blocked by the industry lobby. The safety upgrades are much-needed, as one quartewr of the US reactors are the same model as the destroyed reactors at Fukushima. Some people are fearing that the next Fukushima disaster will happen in the USA.

The standard worker dose limit for Japanese workers is 50 mSv/year and 100 mSv over 5 years. Before the accident, the emergency dose limit was set at 100 mSv/year but was raised to 250 mSv/year to allow workers to respond to this serious accident.

Economicsandnuclearsafetyareatodds

Quality control and dependency of inspections

Economic arguments may also lead to reduced quality controls by official inspectors. In France an ex-CEO of the state-owned utility EdF officially advised the French government to reduce the role of an independent quality controlling institute, in this case the Autorité de Sûreté Nucléaire (ASN), the French Safety Authority. Development at the US National Regulatory Commission (NRC) and incidents at nuclear power stations in the USA point to a similar trend. How is the situation in other countries?

In a number of countries the nuclear industry urges simplified and shortened license procedures to speed up construction of new nuclear power plants, with minimalisation or even eliminiation of the participation by the local authorities and the public. Evidently such a development does not enhance nuclear safety nor the democratic character of the energy policy.

Healthrisksofnuclearpowerareaneconomicallydefinednotion.

Forwhatreasonsdowethinktoneedabsolutelynuclearpower?Aren’ttheresaferalternatives?

Howmucharewewillingtopayforthehealthofourselves,ourchildern,grandchildernandfuturegenerations?

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i27

Diluting nuclear waste

Fallacy

Diluting an amount of radioactive substance with an infinite amount of non-radioactive material will reduce the radioactivity of the mixture to nearly the natural levels and make the radioactive waste nearly as harmless as the diluting materials. How sound is this view?Looking closer it turns out to be another fallacy in the nuclear world:• Evidently diluting infinitely is not feasible. That means that the mixture always will be

considerably more radioactive than the diluting material. • Nuclear waste contains a large number of different radionuclides and many of them are

highly dangerous, even in very low concentrations. The radioisotopic composition of diluted waste is completely different from naturally occurring weakly radioactive materials. What counts are the types of radionuclides in the waste and their biological behaviour.

• It is a misconception to think that naturally occurring radioactivity would be harmless. Uranium-bearing rock, for instance, contains a number of very dangerous radionuclides, such as polonium-210. In addition to their radiotoxicity these radionuclides are chemically very toxic [more i18].

Increasing health risks

Larger waste volumes increase the chances that humans will come into contact with radioactivity from that waste and greatly enhances the probability that the radionuclides will enter the food chain. This may raise ethical questions like: What would be more acceptable to individuals: a certain chance of ingesting 100 lethal doses or a hundred times greater chance of ingesting one lethal dose?

Low-level waste

Radioactive waste is generally classified low-level waste (LLW) when the gamma radiation measured outside of the waste container is below a certain level, so much that the exposure of workers handling the waste containers is kept below a given standard. This radiation level is not unambiguously defined and may be different from one country to another. Below a certain gamma radiation level the waste is classified as non-nuclear waste and safe to be released into the public domain, for example uranium mining waste [more i18]. The standards are sensitive to economic priorities [more i26].

Why are these standards not the same in all countries? On which scientific grounds and empirical data are the standards of ‘low-level’ and ‘safe’ based?

Are these standards valid for the general public, in case of chronic exposure to ‘low-level’ and ‘safe’ nuclear waste?

Do these standards incorporate the health risks posed bythe widely different radionuclides

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which may be present in the waste, including the barely detectable ones, such as tritium and carbon-14?

Who monitors and controls the regulations and classifies the batches of radioactive waste? How does the classification of radioactive wastes work out in practice, in all countries with nuclear power?

Chronic exposure to doses of radioactivity which are ‘low’ according the current official standards have serious health effects with the exposed people, as has been proven by large epidemiological studies in Germany and France.

Military practice

Military nuclear facilities in the USA and other countries did dilute nuclear wastes by soil in the past, simply by letting the liquid wastes leak into the ground and ground water, via ‘storage’ ponds or otherwise. In the former Sovietunion large lakes and rivers are so heavily contaminated that the surrounding regions became inhabitable. Up until the 1990s large amounts of nuclear wastes, including complete reactors, have been dumped into the sea: diluting by sea water.

Civil practice

The amounts of radioactivity in the waste from civil nuclear installations may be a factor 100 larger than from military nuclear activities. Diluting radioactive wastes by air and (sea) water is common practice in the civil nuclear industry. Large amounts of radioactive materials are routinely discharged by reactors.Reprocessing plants are discharging even larger amounts of radionuclides, including fission pro-ducts and actinides. This practice is an essential part of their ‘waste reduction’ policy. Not by chance the reprocessing plants of France (La Hague) and the UK (Sellafield and the now closed Dounreay facility) are situated at the sea shore [more i17, i19, i31]. The consequences of this practice are observable. Some nuclides cumulate in the food chain, for example iodine in seaweed. In the sea off the coast of Norway lobsters have been catched with a significant plutonium content. Seafood is rarely or never checked on its radioactivity content.

Decommissioning and dismantling waste

Massive amounts of radioactive waste will result from dismantling nuclear power plants and reprocessing plants [more i20]. The radioactivity content of the ruble and scrap resulting from contamination and neutron radiation will vary widely from batch to batch, as will the radioisotopic composition. All radioactive wastes have to packed properly and placed into a geologic repository. The high costs may easily provoke hazardous situations. Economic priorities may lead to relaxation of the regulations to admit higher concentrations of radioactiviy in the debris admitted for clearance for unrestricted use in the public domain [more i26]. The IAEA proposes to dilute radioactive materials, such as scrap originating from dismantling nuclear-related installations, with non-radioactive materials, to be used for ‘special purposes’. This is a hazardous proposal for it is inherently uncontrollable.

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i28

Nuclear renaissance

World nuclear capacity In 2012 the world nuclear electricity generating capacity was 370 GWe (gigawatt electric power), generating about 14% of the total world electricity and some 1.9% of the total world energy supply [more i05]. At present more nuclear power plants are facing the end of their operational lifetime and are closed down than new ones are coming online. Without new nuclear build the current world nuclear fleet, including the plants under construction at this moment, would be closed down by the year 2050-2060.

The nuclear industry tries to reverse the declining trend and vigorously promotes a nuclear renaissance: a new era of expanding nuclear capacity. In some scenarios of the nuclear industry a world capacity of 1500 GWe (gigawatt electric power) by the year 2050 is envisioned, four times the current capacity of 370 GWe.How probable is such an envisioned nuclear renaissance?

To keep the world capacity at the current level nearly the whole fleet of presently operating nuclear power stations has to be replaced by the year 2050. This would imply a construction program at a rate of 9 units connected to the grid each year, about the highest observed rate in the past.On top of this building program the capacity would have to be expanded fourfold. That would imply a constuction rate of 35 new nuclear power plants connected to the grid each year worldwide, ten times the current rate.

Adoption curve

The graph of the world nuclear capacity over time exhibits a remarkably smooth S-curve. Such a curve is typical for the adoption of new technologies in social systems: first the development phase and slow growth, than the introduction phase with exponential growth and finally a phase in which a level of maximum implementation is reached. Curves similar to the nuclear capacity versus time curve exist, for example, with regard to the initial development of the internal combustion engine and the gas turbine [more i29].

How likely is a nuclear renaissance?

Innovative nuclear technology, needed to start a new adoption curve development, will not hold its 50 years old promise, because the envisioned advanced nuclear concepts turned out to be unfeasible, an observation based on the fundamental laws of nature [more i30]. This implies that a nuclear renaissance has to be based on the currently available nuclear power technology. A nuclear renaissance based on the present state of technology seems not very likely for several reasons:

• The global production capacity of nuclear power plants of the current state of technology is

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not able to keep the global nuclear capacity flat at the present level, let alone an increase would be possible.

• The present nuclear fleet depends on the availability of high-quality uranium resources. These resources will get exhausted by the year around 2050. The chances of discovery of new very large high-quality uranium resources, needed to feed a nuclear renaissance, seem very dim, in view of the evidence of the past decades. Unconventional uranium resources, such as phospate rock, shales and uranium from the sea, are no option, for reason of the prohibitive amounts of materials and useful energy required to exploit these sources, not to speak about the damage to the biosphere caused by exploitation of these unconventional resources [more i38].

• The much advocated low-carbon property of nuclear power will evaporate over time, due to the CO2 trap [more i05].

• Nuclear power is extremely material-intensive [more i13] and consequently energy-intensive. The production of the high-grade materials required for the nuclear process chain will become increasingly energy-intensive, due to depletion of the highest-quality mineral resources [more. As a result the energy balance of nuclear power will decline over time. This effect comes on top of the energy cliff [more i38].

2000 2020 2040 206019801960

400

worldnuclearcapacity(GWe)

year

forecast

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Figure 28-1. World nuclear capacity, past and future.The nuclear capacity does not equal the actually operating capacity. The blue bars represent the historic

nuclear capacity and include the nuclear power stations shut down in Germany and Japan after the

Fukushima disaster. The nuclear cpacity will gradually decline during the next decades due to the closedown

of power plants reaching the end of their operational life. This forecast is based on on the known ages of

the currently operating reactors and on the number of reactors at present under construction or planned.

Average operational lifetime is assumed to be 40 years.

To keep capacity at the current level by 2050-2060 as much nuclear power plants have to be built by

that year as has been done during the past decades. Such a construction program would mean a nuclear

renaissance in itself.

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i29

Adoption of innovative technology

History of nuclear power

From the time the first nuclear power stations came online in the 1950s the world nuclear capacity grew exponentially during 1960s and 1970s. During the 1980s and 1990s the capacity started leveling off and remained about constant during the last decade. At present more nuclear power plants are reaching the end of their operational lifetime than new ones come online. Without new nuclear build the current world nuclear fleet would be closed down by the year 2050-2060.

The graph of the world nuclear capacity over time (Figure 29-1) fits remarkably well a smooth S-curve, known in mathematics as the logistic function (Figure 29-2). The logistic curve is typical for the adoption of innovations among organisations and social systems and is therefore also known as the adoption curve or diffusion curve.First the phase of early adopters of the innovation and slow growth of the number of adopters, than an adoption phase with exponential growth and finally a phase in which a level of maximum adoption of the innovation is reached. Curves similar to the nuclear capacity versus time curve exist, for example, with regard to the diffusion of the steam engine into the economic system in the 19th century and of the internal combustion engines and the gas turbines in the 20th century. The adoption curve is also common with the introduction of new technologies for the consumer, for example the color tv, cellphone, computer and internet,Most new technologies follow a similar maturity lifecycle: from early development to maturity and implementation, to obsolescence and phase-out.

Maturity and obslescence of nuclear power

From the constant level of the world nuclear capacity during the past decade one may conclude that nuclear technology has reached the phase of maturity. This observation seems to be in conflict with the fact that the costs of nuclear power plants are still escalating and are hardly controllable. Likely the chronic cost escalation of nuclear projects has other causes than technical immaturity: the tremendous complexity of the nuclear energy system and the fact that nuclear power never has been, and never will be, independent of massive state support, directly as visible financial streams and indirectly via disguised channels.

In view of the foreseeable decline of the world nuclear capacity during the next decades, the current nuclear technology is entering obsolescence. A gradual phase-out of the current nuclear power technology seems inevitable. This observation is sustained by the declining availability of high-quality uranium resources, on which the viability of current nuclear power plants is based [more i28, i38].

Historic evidence concerning the diffusion of new technologies in social systems, following the adoption curve, shows that large-scale adoption of a new technology occurs only when the new technology offers possibilities existing technologies did not. A technology becomes obsolete

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when other technologies emerge which are better suited to perform the same task.

An expansion of the nuclear capacity on top of the existing adoption level of nuclear power would imply the availability of a new technology so innovative that it would initiate a vigorous adoption process, not only able to replace the adopters of the existing nuclear technology, but also able to reach a new extra group of adopters. Such a development would be thinkable only by the introduction of an innovative nuclear technology, so powerful that it could oust other energy technologies. Even to keep the world nuclear capacity at the current level the introduction of an innovative technology would be needed, to replace the currently operating power plants, which are of obsolete technology.

Likely the nuclear industry, off course aware of the adoption curve, has the breeder cycle and probably also partitioning and transmutation as energy source in mind [more I32, I33 and I34].However, these ‘revolutionary new’ nuclear technologies are not so innovative as the nuclear industry wants the public to believe and will remain feasible only in cyberspace. The Second Law of thermodynamics is relentless [more i39 and i43].

2000 20101990198019701960

400

0

worldnuclearcapacity(GWe)

year

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Figure 29-1. World nuclear operating capacity.In May 2012 the world nuclear capacity amounted to 370 GWe.

time

stationarystateadopters

(cumulative)

exponential growth

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Figure 29-2. Adoption curve of innovative technologies.This logistic curve represents the cumulative number of adopters of an innovative technology as presented

in Figure 29-3.

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time

late majority

laggards

early majority

early adopters

innovators

adopters

© Storm

Figure 29-3. Innovation adoption lifecycle.According to a generally accepted theory on the diffusion of new, innovative technologies or ideas in

social systems, individuals can be classified into five groups: innovators, early adopters, early majority,

late majority and laggards. In regard to nuclear power, the first two groups may be found in the USA, UK

and former Sovietunion; laggards may be found for example in China.

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i30

Advanced nuclear concepts

Advanced reactors and concepts of waste reduction

The nuclear industry seems to be convinced that advanced nuclear technology will provide the solutions to problems that may emerge in the future, especially uranium shortages and radioactive waste handling. A number of advanced concept are being promoted, such as:• Recycling of plutonium and uranium in LWRs [more i32] • Breeder reactors for high utilization of uranium [more i33]• Reduction of radioactive waste hazards by partitioning and transmutation [more i34]• Use of thorium for production of nuclear fuel [more i35]• Reduction of radioactive waste by reprocessing [more i36]• Nuclear fusion [more i37].

Each of above concepts will be discussed briefly in separate items on this website. Of these proposed technologies only recycling of plutonium in light-water reactors (LWRs) is being practiced on limited scale in a small number of nuclear power stations. The other technologies are actually old promises from the nuclear industry, dating back from the 1950s and 1960s, but did not materialize. The nuclear industry asserts that these developments has been terminated for economic reasons and/or political unwillingness. In practice these technologies proved to be physically unfeasible by fundamental limitations, and consequently they proved to be economically not viable.

A single process turns out to be crucial for the feasibility of all of these concepts: the reprocessing of spent nuclear fuel. For that reason this issue will be addressed separately [more i31].

Aerospace Plane

Technical dreams are not typical of nuclear technology. A parallel of the failure of the breeder cycle in nuclear technology can be found in space technology: the development of the Aerospace Plane during the 1980s and 1990s. This craft was envisioned to be able to lift off like a plane with jet engines from a conventional airport, accelerate to hypersonic speeds within the atmosphere by means of scramjets and to orbital speed in the rocket mode of its engines. The spacecraft would return to a conventional airfield in a unpowered aircraft mode.The heavily promoted concept of the Aerospace Plane proved to be unfeasible for the same reasons as the failure of the breeder and thorium cycle: the limitations to materials and structures set by the Second Law of thermodynamics [more i39, i41].

Advanced uranium recovery

Probably the nuclear industry has also advanced concepts of uranium recovery in mind, expecting that advanced technology will make it possible to recover uranium at an affordable price from unconventional sources, for example seawater. However, the energy cliff is based on natural laws, not on economic notions [more i38].

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Reprocessing

Outline

Reprocessing is the name of a complex sequence of separation processes, aimed at separation of spent nuclear fuel into several fractions: • plutonium, generated in the reactor from uranium by neutron absorption,• left-over uranium, only a small fraction of the uranium in fresh nuclear fuel has been fissioned or transmuted into plutonium in the reactor,• fission products,• actinides, the heavy radionuclides formed from plutonium by neutron absorption,• cladding hulls of the nuclear fuel elements.

Dissolving the spent fuel in boiling nitric acid is the first step of the reprocessing sequence. The zirconium cladding hulls of the fuel elements do not dissolve. In subsequent steps the various fractions are chemically separated form the solution. The recovered plutonium and uranium are purified to high standards, suitable for reuse in nuclear reactors.

Discharges into the environment

The gaseous and volatile fission products escape from the solution and are released into the air and/or sea via waste water. A number of fission products that are difficult to incorporate into inert solids. A significant fraction of these radionuclides are also discharged into the waste water.

Because of the massive releases of radioactive substances into the environment, reprocessing is an exceedingly polluting process. Europe has two operating reprocessing plants: at Sellafield in the UK and at La Hague in France. Both plants are situated at the sea coast, for obvious reasons.

Practice

Separation processes are governed by the basic laws of nature, among other the Second Law of thermodynamics. One of the consequences of these laws is that separation processes never go to completion. This fact results in the observation that it is impossible to separate a mixture of different chemical species into 100% pure fractions without losses [more i42]. Separation becomes more difficult and goes less completely as:• more different kinds of species are present in the mixture,• the concentration of the wanted for species in the mixture are lower,• constituting species are chemically more alike.

In addition radioactivity seriously hampers chemical separation processes, due to breakdown of the separating chemical by nuclear radiation. Radioactive and non-radioactive isotopes of the same element cannot be separated.

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Spent fuel is an extremely complicated mixture of many dozens of chemical species: the whole Periodic System of the elements is represented in spent fuel. This results in the occurrence of substantial losses in the separation processes to obtain pure uranium and plutonium and the fact that the recovered metals are easily contaminated with other elements with similar chemical properties. Losses and impurities increase with increasing radioactivity of the mixtures.

Costs

Reprocessing is a very costly process, consuming large amounts of energy and materials and requiring massive buildings and storage facilities. The investment costs are extremely high and often (partially) covered by secret contracts with the customers. The operational costs must be very high, but are not known publicly. In the period when the ‘commercial’ reprocessing plants (La Hague, Sellafield) have been built (1970s-1980s) high costs were no issue, for the recovered plutonium and uranium were expected to be fissioned in breeder reactors a hundred times more efficient than in the common reactors. Consequently the fuel cost of breeder fuel could be high compared to common enriched uranium without a significant impact on the electricity price.

At the end of its operational lifetime the reprocessing plant has to be decommissioned and dismantled. Then the facility is heavily contaminated with all kinds of radioactive materials, so decommissioning and dismantling will be a challenging task. For Sellafield in the UK the preliminary cost estimate of this task amounts already to some €100bn, more than the costs of the complete Apollo project of the USA, which succeeded in the landing of six crews on the Moon in the period 1969-1972. The huge amounts of radioactive waste from the dismantling of a reprocessing plant, heavily contaminated with all kinds of radionuclides, might pose serious hazards [more i20, i27].

Historic purpose

Reprocessing technology has been developed during the late 1940s and Cold War to recover plutonium for weapons. In the following decades the technology has been further developed to reprocess spent fuel from civil nuclear reactors. Purpose was the recovery of the plutonium and unused uranium to fuel the envisioned breeder reactor. The large civil reprocessing plants at La Hague (France) and Sellafield (UK) have been built during the 1970s and 1980s in the belief that uranium and plutonium recycling in the breeder cycle (LMFBR: Liquid-Metal-cooled Fast Breeder Reactor) would soon become the base of civil nuclear power [more i33].

When it became evident – though not admittedly – that the breeder cycle would not be feasible within a foreseeable future, the nuclear industry quietly switched to other arguments to justify the exceedingly high cost of reprocessing:• recycling of plutonium in MOX fuel in modern light-water reactors [more I32],• volume reduction of the high-level nuclear waste [more I36],• shortening the radioactive half-lifes of long-lived hazardous radionuclides by partitioning

and transmutation [more I34].

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gaseous effluents

liquid effluents

volatile nuclides

dismantlingwastes

solids glassliquids

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H-3 C-14 Kr-85 I-129 Xe-133actinides (aerosol)

fission products

actinides

H-3 C-14I-129

Sr-90 Tc-99 Ru-106Cs-137 and other

activation products

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spent fuel

Figure 31-1. Outline of reprocessing of spent nuclear fuel.Reprocessing is a complicated sequence of separation processes, aimed at the recovery of newly formed

plutonium and remaning uranium from the dpent nuclear fuel. The other radioactive consituents of spent

fuel are distributed over large volumes of six waste streams, two of which are released into the human

environment. For that reason reprocessing is an exceedingly polluting process. A part of the radionuclides

from the spent fuel is vitrified, meaning that the radionuclides are chemically fixed in a borosilicate glass.

The volume of this glass is very small compared to the other waste streams. When the nuclear industry

states that nuclear power produces little waste, they refer to only this glass. The other waste streams are

not less dangerous and their volumes are much greater, so there is more chance of inadvertent releases

of radioactivity into the human environment. The volumes of the decommissioning and dismantling waste

of a reprocessing plant may amount to hundreds of thousands cubic meters. This waste stream is never

mentioned by the nuclear industry.

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Recycling of plutonium and uranium (MOX) in LWRs

Plutonium energy balance

Per metric tonne recovered plutonium the decommissioning and dismantling costs alone are estimated at more than €1bn. To provide one nuclear power plant with a first core of MOX fuel (Mixed OXide, a mixture of plutonium and uranium oxide) instead of conventionally enriched uranium, 6-7 tonnes of plutonium is required. Consequently the first core with MOX fuel will cost about as much as the construction of the nuclear power plant itself, if the decommissioning costs are accounted for.

Obviously the decommissioning and dismantling of a reprocessing plant will require investment of massive amounts of energy. By means of the energy analysis methodology these energy investment can be estimated and turns out to be about as large as the maximum energy production possible per recovered mass unit plutonium. Besides, the decommissioning and dismantling energy investments have to be added to those of the construction plus operation and maintenance of the reprocessing plant, which are also substantial.

From above observation follows that the recycling of plutonium in the current generation of nuclear reactors, by means of MOX fuel, has a negative energy balance. That means that pluto-nium recycling would consume more energy than it adds to the net energy production. A large part of the necessary energy investments are passed on to the future generations: an energy debt [more i16].

Terrorism threat

Plutonium recycling unavoidably generates uncontrollable risks of nuclear terrorism and proli-feration. Using elementary chemistry MOX fuel can be separated into uranium and plutonium. The plutonium could be used to produce a crude nuclear weapon. Evidently such a weapon wouldn’t have the reliability and yield of a military weapon, but even a nuclear explosion of a few kilotons in the center of a town could be devastating. Even without a nuclear explosion the dispersion of several kilograms of plutonium over a town by a small plane may render the town inhabitable.

Uranium

Reprocessed uranium can only be used in MOX fuel, because its fissile content is too low to sustain a fission process in a reactor. Enrichment of reprocessed uranium to appropiate levels by means of diffusion or ultracentrifuge is not feasible, due to its high radioactivity and un-favourable isotopic composition. Reprocessed uranium contains uranium-234 and uranium-236 isotopes, which are highly radioactive and non-fissile. Enrichment of reprocessed uranium me-ans also enrichment in U-234 and U-236. As a consequence the fissile component of nuclear fuel has to be plutonium. Fuel fabrication from reprocessed uranium has to be done by remotely controlled equipment, due to the high radioactivity of the material.

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For reasons explained above the reuse of reprocessed uranium in nuclear fuel will result in a negative energy balance of nuclear power.

View of the nuclear industry

he optimistic view of the nuclear industry with respect to the recycling of plutonium seems to be based just on short-term economic arguments.

Apparently the nuclear industry is convinced that regulations conceived on paper offer water-tight guarantees against terrorism with MOX fuel.

The view of the nuclear industry lets no room for decommissioning and dismantling of repro-cessing plants and the energy balance of plutonium recycling appears to be a non-item. The energy investments and financial costs of the plutonium recovery are not accounted for and not balanced with other investments.

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Breeder reactors

Once-through mode

In a nuclear reactor of current state of technology in the once-through mode – all power reactors operating today are falling in this category – not much more than about 0.6% of the atoms in the natural uranium recovered from its ore can be fissioned. This has to do with the isotopic composition of natural uranium, only a small fraction is fissile. By neutron capture – neutrons are set free during fission of uranium-235 atoms – the non-fissionable uranium-238 atoms can be transformed into plutonium atoms, most of which are fissile. For that reason uranium-238 is coined a fertile material.

Uranium-plutonium breeder concept

The idea behind the U-Pu breeder reactor is to use the plutonium from a number of LWRs to load a special kind of reactor with a core with plutonium as fissile material surrounded by uranium-238 as fertile material. In this reactor, cooled by a liquid metal and operating with fast neutrons, it would be possible to generate more fissile plutonium from uranium-238 in the blanket than is fissioned in the core during operation of the reactor. For that reason this kind of reactor is called a fast U-Pu breeder reactor, which does not mean that the breeding process goes fast.

The spent fuel from the breeder reactor would have to be reprocessed to separate the fission products, which interfere with the fission process. From the remaining uranium and newly formed plutonium fresh nuclear fuel would be produced and placed into the reactor. By repeating this cycle again and again it would be possible to fission about 60% of the atoms in natural uranium, some sources even claim 100%. This theoretical concept is the source of the dreams and promises of the nuclear industry of ‘unlimited energy, too cheap to meter’.

Breeder cycle

In practice the breeder concept involves a cycle of three processes: breeding in the reactor, reprocessing of spent fuel and fuel fabrication. Each of the three components of the breeder cycle must operate flawlessly, continuously and exactly tuned to the other two components, in order to let the system actually breed more fissile material from non-fissile uranium than it consumes. If one component fails, the whole system fails. In fact, none of the three components have ever demonstrated operation as required, let alone the three components together as one integrated continuously operating system. Process losses occur in each of the three components, resulting in a breeding ratio less than unit, even if all would operate as planned. A breeding ratio less than unit means that the cycle generates less fissile plutonium than it consumes, so during the operational lifetime of the breeder cycle the reactor has to be supplemented with plutonium from conventional reactors.

During the past 50 years intensive research has been conducted on the U-Pu breeder concept

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in a number of countries (USA, UK, France, Germany, former Sovietunion and Japan). The investments amount to more than $100bn. The international research was concentrated on the LMFBR, the Liquid Metal-cooled Fast Breeder Reactor, a heavily promoted concenpt during the 1980s and 1990s. All efforts failed.

New names, no new concepts

Presently the nuclear industry avoids the term ‘breeder’ or ‘LMFBR’ and uses preferably the terms ‘fast reactor’ or ‘Generation IV reactor’ or ‘closed-cycle reactor’. When speaking about these reactor types the nuclear world usually has fast U-Pu breeder reactors (LMFBR) in mind. From a publicity point of view this change of name has an understandable reason, because the concept proved to be technically unfeasible and consequently ‘breeder’ and ‘LMFBR’ connote failed concepts.

The failure of the breeder concept is not caused by protests of environmental activists or by actions of leftist politicians, nor for economic reasons, as the nuclear industry asserts, but is caused by fundamental technical limitations. Implicitely the nuclear world assumes the avai-lability of 100% perfect materials and 100% complete separation processes. None of these two conditions are possible, as follows from the Second Law of thermodynamics. By virtue of this law can be argued beforehand that the breeder cycle likely will not work [more i42, i43].

electricity

discharges

discharges discharges

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U + Pu+ actinides+ fission products+ activation products

actinides

fission products + activation products

fresh fuelU + Pu

natU

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U + Pu loss U + Pu loss

U + Pu

PuUdepl

initial charge

spent fuel

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Figure 33-1. The breeder cycleThe breeder reactor is not a stand-alone system, but part of a cycle of three components: a special reac-

tor, a reprocessing plant and a fuel fabrication plant. The cycle has to be started up with plutonium recov-

ered from spent fuel from conventional reactors. The spent fuel from the liquid-metal cooled fast reactor

has to be reprocessed to remove the fission products, activation products and actinides. The recovered

uranium and plutonium would be reused. Due to rapidly increasing radioactivity of the spent fuel with

each cycle, reprocessing and fuel fabrication become increasingly difficult. The isotopic compositions of

the recovered uranium and plutonium become less favourable each cycle. Due to the unavoidable and

increasing separation losses, the cycle produces less fissile nuclides than it consumes. For these reasons,

among other, the breeder cycle is technically unfeasible.

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Partitioning and transmutation

Radioactivity of spent nuclear fuel

Spent nuclear fuel when removed from a nuclear reactor is a billionfold more radioactive than fresh fuel (enriched uranium). During the first year after removal the radioactivity of the spent fuel falls with a factor 100 by natural decay of short-lived radionuclides. During the next four centuries the radioactivity decreases another factor 100 by natural decay. From then on the radioactivity decreases very slowly: another factor 100 takes ten million years. After ten million years of cooling the specific radioactivity of spent fuel, measured in radioactivity units per kilogram (Bq/kg), is still nearly ten million times higher than the natural level of the human body [more i10].

Concept

The idea behind the partitioning & transmutation concept is to reduce the hazards posed by the radioactive content of spent fuel. Theoretically there are three conceivable ways to achieve this aim:• Conversion of long-lived radionuclides into short-lived radionuclides, Then the waste would

remain dangerous for a shorter time, so less demanding permanent storage facilities would be appropiate.

• Conversion of radionuclides into stable nuclides. Then the amount of radioactivity in the nuclear waste would be reduced.

• Conversion of the most dangerous radionuclides into less dangerous ones. Then the radiotoxicity of the nuclear waste would be reduced.

If the long-lived radionuclides could be converted into short-lived or stable nuclides, the concentrations of the long-lived dangerous nuclides in the remaining wastes could be reduced to below an official standard, so it would be safe for release the waste into the environment after a storage time of only a few centuries. At least, the amount of high level waste to be stored permanently in a geologic repository would be reduced to a small fraction of the spent fuel.

Transmutation

The conversion of atoms by neutron capture into other atoms is called transmutation.In an operating nuclear reactor, where free neutrons are present, radionuclides can be converted into other radionuclides or into stable nuclides. Likewise the reverse process works out: stable nuclides are converted into radioactive nuclides. The net result is always an increase of the radioactivity of the reactor and its contents. In fact the generation of plutonium from uranium-238 in a common nuclear reactor is a transmutation process, but also activation, the unintended process by which non-radioactive construction materials become radioactive. Neutron capture is a random process: it occurs by chance, because the randomly moving neutrons in a reactor cannot be directed at a specific nuclide.

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Minor actinides

The nuclear industry focuses its research on the transmutation of the so-called ‘minor actinides’, that are the heavy radionuclides which are formed by neutron capture of plutonium nuclides. The designation ‘minor’ regards the relatively small amounts of these radionuclides, compared to the amount of plutonium [more i11]. The minor actinides have long half-lifes (thousands to millions of years) and are extremely dangerous in the human body.

The nuclear industry asserts to be able to fission the minor actinides, so they will contribute significantly to the nuclear energy production. However, the amounts of fissile minor actinides are negligible compared to the amounts of fissile uranium and plutonium, even in closed-cyclereactor systems, such as the breeder [more i33].

Apart from the minor actinides a number of other long-lived radionuclides are present in nuclear waste, which seem to be ignored by the nuclear industry.

Partitioning

For reason of the fact that neutron capture is a random, non-selective process, the spent fuel has to separated into a number of partitions: uranium, plutonium, actinides other than plutonium, lanthanides plus one or two other partitions. Partitioning is required to remove as much as possible those radionuclides or stable nuclides which would generate unwanted radionuclides in the transmutation cycle, or would interfere otherwise.

Radioactive isotopes cannot be separated from non-radioactive isotopes of the same chemical element, because partitioning is based on chemical separation processes. In fact partitioning is a more complicated version of reprocessing of spent fuel [more i31]. Another word does not mean another process with less problems.

Outline

A partitioning & transmutation system consists of a cycle of three components: a transmuter reactor, a partitioning plant and a plant for fabrication of fuel elements and target elements. The fuel elements are needed for a sustained fission and neutron generation in the reactor, the target elements contain the radionuclides te bo irradiated by neutrons for transmutation. After a certain period in the transmuter reactor, the target elements have to be removed and to treated in the partioning plant again, to separate fission products from it. From the remaining amount of transmutable radionuclides new target elements are to be fabricated, which can be placed in the transmuter reactor.The partitioning & transmutation cycle is much alike the breeder cycle, albeit more demanding. All three components have to work nearly flawlessly and finely tuned to each other, during many decades, if the system were to work as planned.

The target elements, containing the radionuclides to be transmuted, have to be recycled repeatedly. Each cycle increasing the radioactivity of the material will increase and the concentration of radionuclides exhibiting spontaneous fission will rise. This will render the material unmanageable and will increase the chance of criticality incidents in the separation processes, igniting small nuclear explosions.

Even if the transmutation system would work as advertised, it would have its limitations:• On nuclear-physical grounds only a limited number of the many kinds of long-lived

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radionuclides in nuclear waste are candidate for transmutation, so the waste reduction would be marginal at best.

• It would take centuries (!) to reduce a given quantity of a specific radionuclide with a factor 100, Only a small fraction of it can be transmuted in one cycle, so the amount has to pass through many cycles to achieve a significant reduction.

Feasibility

The concept of partitioning & transmutation is implicitely based on the assumed availability of 100% perfect materials and 100% complete separation processes. None of these two conditions could be met, as follows from the Second Law of thermodynamics [more i42, i43]. By virtue of this law can be argued beforehand that the transmutation cycle will not work as advertised. Worse still, it would be counterproductive:• A transmutation system would produce more radioactivity than it starts with and would

generate more long-lived radionuclides, of other kinds, than it would reduce.• The energy consumption of a transmutation system would be prohibitive. The partitioning

and target fabrication have to be performed robotically, if it would work at all, due to the extremely high radioactivity of the materials. The energy production by fission of the actinides would be negligible.

• As a result of the increase of radioactivity in the transmutation cycle, the required long operation periods and the increased number of facilities containing highly radioactive materials, intended and unintended discharges of radioactivity into the human environment would sharply increase by the implementation of the transmutation cycle.

The partition & transmutation concept is unfeasible due to fundamental technical limitations. The question rises for what reasons the nuclear industry promotes this concept.

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Figure 34-1. Partitioning and transmutation system outline.A partitioning and transmutation system is in concept similar to the breeder system concept. The input

of the transmutation cycle would comprise uranium, chemicals and spent nuclear fuel, containing fis-

sion products, activation products and actinides. The output of the system would consist of more fission

products and activation products than went into the system and less actinides than the input, if the cycle

would work. In addition a appreciable part of the radioactive content of the transmuter cycle would be

discharged into the human environment. What to do with the highly radioactive output of the system

remains an unanswered question in the proposals of the nuclear industry.

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liquid effluents

gaseous effluents+ aerosols

dismantlingwaste

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liquidwaste

plutonium

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Figure 34-2. Partitioning of spent fuel.Actually the partitioning of spent fuel and irradiated targets would be a more complicated version of re-

processing. More demanding because the spent fuel would have to be separated into more pure fractions

than in a conventional reprocessing procedure and because of the extremely high radioactivity of the

irradiated targets. Partitioning would produce large volumes of radioactive waste, a part of which would

released into the human environment.

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Thorium-based nuclear power

Thorium cycle

Thorium is a radioactive metal, slightly more abundant in the Earth’s crust than uranium and with similar chemical properties as uranium. The concept of the thorium reactor is based on the conversion by neutron capture of non-fissile thorium-232 atoms into uranium-233 atoms, which are fissile. The use of thorium as nuclear fuel would imply a breeder cycle, similar to that of the uranium-plutonium breeding cycle.

A thorium reactor would consist of an active reactor core in which fissile nuclides are fissioned, surrounded by a blanket with thorium-232. The active core would generate heat for power generation and the neutrons for the transmutation of thorium-232 into uranium-233. After a given amount of absorbed neutron radiation the material would be removed from the blanket and transported to a reprocessing plant. There the material would be separated into several fractions: remaining thorium-232, newly formed uranium-233 and unwanted nuclides. The thorium would be replaced into the blanket of the reactor and the uranium-233 would be used to fabricate fuel elements for the core of the reactor.

Research and development on the thorium cycle has been less intensive than on the U-Pu cycle and never reached the prototype phase. Among a number of other countries, the USA conducted Th-232/U-233 research in the 1960s and 1970s. For unclear reasons the research has not been continued.

Uranium-233

Uranium-233 does not occur in nature, due to its relatively short half-life of 158000 years. In the USA, during the 1950s and 1960s, U-233 has been envisioned as fuel in very compact military reactors for special applications, e.g. for electricity generation on remote locations and in large (military) spacecraft, in nuclear-powered rockets and even in a nuclear-powered bomber. Although U-233 reportedly would have about the same properties as plutonium for use in nuclear weapons, no such weapons seem to have been developed. Undoubtedly the former Sovietunion also has done research on the use of thorium, but little is known about that.

Apparently there exist good reasons not to use U-233 in military reactors or in weapons and to discontinue the research towards the thorium power reactor. The high radioactivity of uranium-233 and unavoidable contamination with unwanted radionuclides impeding the controllability of the fission process in uranium-233 may be a factor. India seems to be the only country at this moment still conducting some research on the Th-232/U-233 fuel cycle.

Only small quantities of U-233 exist in the world at this moment, the USA has 1710 kg of it in storage, 905 kg of which still contained in spent fuel. The U-233 stocks in other countries are unknown. The largest DOE reactor currently operating could produce only about 0.3 kg/year.

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Time frame of any thorium cycle

To generate sufficiently pure U-233, special reactors are required, likely not appropiate for use as power reactors. It would take decades to construct these reactors and to generate sufficient U-233 to start up the first operating Th-U breeder system. Then it would take centuries to attain a thorium breeder capacity equalling the current nuclear capacity (370 GWe), assumed the cycle would work.

Hybrid reactor

A major drawback of the thorium cycle is that a genuine thorium breeder reactor cannot sustain a fission process in itself, but always would need an external accelerator-driven neutron source, or the addition of extra fissile material, such as plutonium or uranium-235 from conventional reactors.

Feasibility

The feasibility of the thorium breeding cycle is even more remote than that of the U-Pu breeder. This is caused by specific features of the thorium cycle on top of fundamental limitations. The realisation of the thorium-uranium cycle would require the availability of 100% perfect materials and 100% complete separation processes. None of these two prerequisites are possible, as follows from the Second Law of thermodynamics [more i42, i43]. It can be argued beforehand that the Th-U breeder cycle will not work as envisioned.

In addition it would be questionable if the energy balance of any thorium fuelled nuclear power system could be positive.

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Nuclear waste and reprocessing

Nuclear waste per kilowatt-hour

Spent nuclear fuel contains per kilogram at average some 35 grams of fission products, 9 grams of plutonium and less than 1 gram of minor actinides, the balance is uranium. The nuclear industry considers only the fission products and minor actinides to be nuclear waste: some 36 grams per kilogram spent fuel. An average nuclear power plant (1 GWe) unloads close to 30 tonnes of spent fuel a year, containing about one tonne of fission products plus minor actinides. During a year the reactor would generate some 3 billion kilowatt-hours of electricity. The waste production calculated in this way would be some 0.3 milligrams of highly radioactive material per kilowatt.hour.These figures are playing an important part in the promotion of nuclear power. The nuclear industry strongly suggest that this tiny amount is the only nuclear waste demanding special attention and is easily controllable. How valid is this assertion?

Volume reduction concept

The idea behind the volume reduction of nuclear waste, is to separate the highly radioactive fission products and actinides from the remaining uranium and plutonium, which are weakly radioactive and would be reusable. The fission products and actinides (other than uranium and plutonium) then are converted into oxides, which are mixed with a glassmaking frit and melted to form a borosilicate glass. The glass is poured into stainless steel containers, which are to be placed in a geological repository for permanent disposal. The vitrified waste would contain 300 grams fission products plus actinides per kg glass, the original spent fuel 36 grams per kg fuel. This would mean a mass and volume reduction by a factor of 8. If this were the whole story, how significant is such a ‘reduction’, considering the exceedingly high investments of energy, materials and human skill in reprocessing?

Misconception

The amount of radioactivity in spent fuel does not change by the mechanical and chemical treatments in the reprocessing plant. Reprocessing simply means a redistribution of the radionuclides from one material to several other. Obviously, mixing an amount of radionuclides, compacted in the small volume of the spent fuel, with non-radioactive fluids or other substances greatly increases the volume of the radioactive waste. The sum of the radioactive contents of all mixtures equals the amount originally present in the spent fuel elements.

Flaws

The concept of waste volume reduction by means of reprocessing does not include the Zircalloy cladding hulls (about 2 tonnes per tonne fuel), which also are highly radioactive, containing long-lived radionuclides and contaminated with insoluble fractions from the spent fuel.

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In spent fuel nearly the full Periodic System of the elements is represented. A considerable number of radionuclides, present in substantial amounts, cannot be vitrified, because these elements do not form stable oxides that can be incorporated into a stable glass matrix.The incompatible elements should to be stored otherwise. However, a significant part of this category is released into the environment (air and sea).

Separation of the components of spent fuel is inherently incomplete. So all fractions from the separation process will be contaminated with undesirable nuclides [more i42, i43].

In the first step of the separation process the gaseous and volatile elements are set free, such as tritium H-3, carbon-14, iodine-129 and the noble gases (e.g. krypton-85, xenon-133). These radionuclides are virtually completely discharged into the environment, along with substantial amounts of other fission products and actinides as aerosolen and dissolved in the waste water stream.

Massive amounts of low-level and medium-level radioactive waste originating from the nuclear process chain, including mining waste, are not accounted for in the waste reduction concept.

Severe problems arise with the borosilicate glass by radiolytic reactions, heat generation, (re)crystallization and segregation of elements. These phenomena may cause a desintegrating of the glass matrix and consequently a high leachability by water of the solid mixture. If not effectively isolated from the biosphere the radionuclides may finally enter the human evironment via drinking water and the food chain. It is not known how long the glass would last in the presence of water.

Radioactive decommissioning and dismantling wastes from the nuclear power plant and the highly contaminated reprocessing plant itself are not included in the waste handling concept. The buildings and equipment have been seriously contaminated with high-level radioactive substances. Experiences with the small reprocessing plant at West Valley in the USA are not encouraging. The cleanup of the West Valley plant will take decades at a cost of at least 40 times the construction cost.

It is not possible to selectively extract solely the radionuclides from all mixtures. Only a part of the radionuclides can be vitrified, inevitably mixed with non-radioactive substances from the spent fuel.

Fallacy

It is a fallacy to think that the hazards posed by the radioactive waste from nuclear power would be proportional to the volume or mass of only the vitrified waste.

The hazards posed by the human-made radioactivity from nuclear power are potentially of unprecedented proportions, in view of the huge amounts generated each year [more i08, i09]. If only a minute fraction of it is released into the environment, the consequences are disastrous. By the Chernoby accident in 1986 less than 0.01% of the world human-made radioactivity inventory has been dispersed into the environment, causing nearly one million casualties, many millions of incurably ill people and extensive economic damage [more i21].

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Least hazardous treatment

The hazards can be reduced to a minimum by reducing to a minimum the chances of releases of the radioactivity into the environment. The safest way to achieve that is to leave the spent fuel elements intact, to pack them in the highly durable containers and to place the containers in a geologic repository as soon as possible. The longer the spent fuel stays in temporary storage, the greater the risks [more i19].

Reprocessing is the most costly and most dangerous way to handle the radioactive constituents of spent nuclear fuel. The radionuclides are redistributed over large volumes of materials, a substantive fraction of the radioactivity is discharged into the environment [more i31] and the chances of severe accidents greatly increase. Accidents will result in inadvertent discharges of massive amounts of radioactive materials into the human environment.

Summary

The nuclear industry asserts that the hazards of nuclear waste are easily controllable, because of the relatively small masses and volumes of the vitrified waste.Scrutinizing the practical aspects of this concept reveals this assertion to be seriously misleading and just short of a lie for several reasons.• The hazards are determined not by the volume or mass of the waste, but by the amounts of

radioactivity, the biochemical behaviour and the radiotoxical properties of the radionuclides and the chance of exposure to the radionuclides in the waste.

• The above noted serious flaws of the waste reduction concept are ignored. In its view the nuclear industry is neglecting the huge volumes of other radioactive wastes, includinig the wastes originating from decommissioning and dismantling nuclear power stations and reprocessing plants.

• If nuclear waste were so easily controllable, why is it still not under control after 60 years nuclear power? Why no definitive solution to the waste problem has ever been achieved anywhere in the world?

Historic motive for reprocessing

The large civil reprocessing plants at La Hague (France) and Sellafield (UK) have been built during the 1970s and 1980s in the belief that uranium and plutonium recycling in the breeder cycle would soon become the base of civil nuclear power [more i33]. When it became evident – though not admittedly – that the breeder cycle would not be feasible, the nuclear industry quietly switched to other arguments to justify the exceedingly high cost of reprocessing, one of those arguments being waste reduction.

Wouldn’t the nuclear industry be aware of the dangers associated with reprocessing spent fuel?It would be hardly conceivable if not. Some forces within the culture of the nuclear industry may explain its view of waste reduction by reprocessing, such as:• downplaying the hazards [more i23]• short-term profit seeking [more i26]• living on credit: après nous le déluge [more i16].

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fission products

fission products

33 g U-235

8 g uranium-235

967 g U-238943 g U-238

plutonium

uranium-236

fresh fuel spent fuel1.000 kg1.000 kg

0.65 g

4.6 g

8.9 g

20.4 g

minor actinides

14.6 g

© Storm

Figure 36-1. Composition of fresh and spent nuclear fuel

gaseous effluents

liquid effluents

volatile nuclides

dismantlingwastes

solids glassliquids

plutonium

uranium



fission products

actinides

H-3 C-14I-129


activation products

© Storm

spent fuel

Figure 36-2. Outline of reprocessing of spent nuclear fuel.In the reprocessing sequence plutonium and remaining uranium are separated from the other constituents

of spent nuclear fuel. The other radioactive consituents are distributed over large volumes of six waste

streams, two of which are released into the human environment. A part of the radionuclides from the

spent fuel can be concentrated and vitrified, meaning that the radionuclides are chemically fixed in a

borosilicate glass. The volume of this glass is very small compared to the other waste streams. When the

nuclear industry states that nuclear power produces little waste, they refer to only to volume of this glass.

The other waste streams are not less dangerous and their volumes are much greater, so there is more chance

of inadvertent releases of radioactivity into the human environment. The volumes of the decommissioning

and dismantling waste of a reprocessing plant may amount to hundreds of thousands cubic meters. This

waste stream is never mentioned by the nuclear industry.

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i37

Nuclear fusion

Hydrogen isotopes

Nuclear fusion, often hailed as the energy source of the future, is based on the fusion reaction between two heavy hydrogen isotopes, deuterium and tritium. If a common hydrogen atom (symbol H) has a mass of 1 unit, then a deuterium atom (symbol D or H-2) has mass 2 and tritium (symbol T or H-3) mass 3, hence the names: ‘deuterium’ means the second and ‘tritium’ the third. Tritium is radioactive and comes into being in nature by reaction of cosmic radiation with molecules high in the atmosphere. The naturally occurring tritium on Earth amounts to less than 9 kilograms. Deuterium is not radioactive and occurs in water molecules, one of every 6700 hydrogen atoms in nature is a deuterium atom. Heavy water consists of molecules with deuterium atoms instead of common hydrogen atoms.

Fusion principle

At temperatures of around 100 millions of degrees celsius deuterium nuclei can fuse with tri-tium nuclei, generating helium-4 nuclei, neutrons and heat. This thermonuclear reaction is applied in the explosion of a hydrogen bomb, in which the required high temperatures and pressures needed to ignite the fusion are generated by the explosion of a fission bomb.The tritium for nuclear weapons is generated in special nuclear fission reactors. Since the start of the atomic age the quantity of man-made tritium worldwide amounts to a few hundreds kilograms, intended for use in nuclear weapons, most of which has decayed during the past decades. Tritium has a half-life of 12.5 years, so after a storage time of 12.5 years, half of each kilogram tritium has been decayed into helium-3, after 25 years 0.25 kg tritium remains. From each kilogram tritium produced in 1962, 62.5 grams still exist today (2012). Consequently the man-made tritium inventory has to be replenished constantly. At present the world tritium inventory is estimated at some 20 kg.

Controlled fusion: a moving target

Understandably the notion of the potentially huge amounts of energy released by the fusion reaction of a tiny amount of matter, as demonstrated by the H-bomb, sparked the research to-wards a controlled fusion process, to construct a reactor which would make available a nearly unlimited energy supply in a controlled and safe way.During the 1960s the nuclear world claimed that first fusion power station would come online within ten years. During the 1970s the first commercial fusion station would come online during the 1980s. During the 1980s the industry assured the first fusion power station would be ready by the year 2000. After the year 2000 the date of the first operating fusion power station moved further into the future to 2050, or later.

Challenges

Before the first fusion reactor can come online, several technical challenges are to be overcome:

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• Stable and continuous operation of the fusion process during tens of years. At present a period of only a number of seconds seems to be within reach.

• Provisions making a run-away fusion reaction and meltdown impossible.• Supply of tritium.• Materials able to withstand very high temperatures, pressures and neutron radiation under

highly corrosive conditions.• Transfer of the fusion heat generated in the reactor to a medium outside of the reactor for

conversion into useful energy (electricity).• Safe handling of unprecedentedly large amounts of tritium, biomedically a dangerous

radionuclide.

Tritium supply

A fusion reactor with an output of 1 GWe (gigawatt electric) needs some 200 kg of tritium to start up, ten times as much as is available world wide at present. Tritium can be generated in nuclear fission reactors and has to be separated from spent fuel, cooling water and/or special target elements for neutron irradiation.

After startup the fusion reactor has to generate on its own the tritium it consumes, tens of kilograms a year. This breeding process would be based on neutron irradiation of lithium-6, one of the natural lithium isotopes, and should occur in the wall of the reactor. After irradiation the contaminants of the mixture have to be removed and the remaining lithium and the newly formed tritium have to be separated and purified.

In addition the contents of the reactor have to be purified constantly, to remove the newly formed helium and the contaminants spallating from the reactor walls during operation. The purified mixture of deuterium and tritium can be fed back into the reactor, with fresh deuterium and tritium to make up the consumed quantities plus the unavoidable losses.

Materials

Deuterium is extracted from purified water. This is a technically mature process and very energy-intensive, the more so if the deuterium has to be prepared from seawater.

The reactor vessel and magnets needed for confinement of the superhot plasma are made of exceedingly high-grade materials, containing exotic and scarce metals, such as columbium (niobium). The life span of a fusion reactor is limited due to the high thermal and mechanical stresses, combined with an intense irradiation of fast neutrons. Likely it will be necessary to replace the reactor vessel a number of times during the operational life span of the power plant. Consequently the consumption of high-grade and exotic materials will be high.

Radioactive waste

Nuclear fusion generates large amounts of radioactive waste. Indeed, no fission products result from fusion, but large amounts of activation products do. The fast neutrons liberated by the fusion reaction irradiate the reactor vessel and surrounding constructions. By neutron capture non-radioactive materials become radioactive, the co-called activation reaction. A part of the liberated neutrons are needed to breed tritium from lithium in the blanket of the reactor, but by far the biggest part of the neutrons escapes from the reactor

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Energy balance

Analogue to fission power nuclear fusion, if ever feasible, would have a process chain:• front end, comprising construction, recovery of deuterium and the production of tritium,• mid section: operation, maintenance and refurbishments, including replacements of the reactor• back end: radioactive waste management, decommissioning and dismantling of the radioactive parts of the fusion power plant.

The first requirement the fusion system has to comply with in order to be an energy source is a positive energy balance, not only of the reactor itself including its containment, plasma confinement and ignition system, but of the complete system.

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i38

Uranium supply

Uranium occurrences

The earth’s crust holds huge amounts of uranium, dispersed over a range of rock types at widely different uranium contents, varying from a few grams uranium per tonne rock to more than 100 kilograms per tonne rock. The lower the uranium content of a rock type, the more of that rock type is present in the crust and the larger the total amount of the metal in that geologic compartment. This is a common geological phenomenon which applies to all metals in the earth’s crust. Obviously it is not possible to extract all uranium from the erth’s crust, not even from the accessible part of it.

Industrial view on resources

The nuclear industry bases its prospects of the future uranium supply mainly on an economic relationship between market price and uranium resources The economic point of view on mineral scarcity can be summarized as follows:• The market price is the criterion of the mining of a metal or mineral. • Higher prices will lead to more intensive exploration. • More exploration will lead to more discoveries of new mineral deposits. • The newly discovered deposits will contain more of the desired mineral than the already known deposits. • At higher price more and larger resources are economically recoverable. Ergo: the world mineral resources, in casu uranium, are practically inexhaustible.

Uranium ores and resources are defined In the mining industry as those deposits that can be exploited economically at the prevailing market price of uranium. Consequently the size of the uranium resources, that are the economically recoverable resources, can increase within a short time when the uranium market price rises.

However, above industrial paradigm is founded on a fallacy, because it ignores the essential difference between the quantity and the thermodynamic quality of uranium occurencies as present in the earth’s crust or oceans. Below we will explain briefly this observation.

Thermodynamic quality of uranium resources

Nuclear fuel, consisting of enriched uranium, is produced from natural uranium which in turn has been extracted from uranium-bearing rock in the earth’s crust. The amount of useful energy required to extract one mass unit of pure uranium from the resources as found in nature varies widely, depending on the geological and mineralogical proprties of the uranium deposits. Usually the ore grade is the most important variable. From the laws of thermodynamics [more i43] follows that the energy investment per mass unit of extracted uranium increases exponentially with declining ore grade of the deposits from which the uranium is extracted. Below a certain grade the useful energy investment per mass

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unit of extracted uranium may be as large as or larger than the amount of useful energy which can be generated from that mass unit. Uranium deposits at grades below the critical threshold, called the energy cliff, are in effect energy sinks, not energy sources. It should be stressed that the threshold is not at a fixed value of the ore grade but is also determined by other variables, such as the mineralogy of the uranium-bearing rock and the depth of the deposit below surface.

The thermodynamic quality of a given uranium resource is here defined as the degree of usefulness of that resource for net useful energy production. The thermodynamic quality becomes zero if the net energy balance of the nuclear system reaches zero and no net useful energy can be generated from the resource in question. The higher the thermodynamic quality of a given uranium deposit (above the critical threshold), the more useful energy can be delivered to the consumer per mass unit of uranium extracted from that deposit.

Depletion of uranium resources

The notion of the thermodynamic quality points to the conclusion that depletion of uranium resources is actually not a matter of quantity, but a matter of quality. From a quantitative point of view the uranium resources may be considered inexhaustible as pointed out above, in accordance with the economic point of view.However, the use of uranium for energy generation puts a lower limit to the uranium content of rocks to be considered an energy source. Below a certain grade of a uranium-bearing rockformation (about 100-200 grams of uranium per tonne rock) the energy balance of the nuclear systems turns negative and no useful energy can be delivered to the consumer, as pointed out above. This observation implies that only a fraction of the uranium occurencies in the earth’s crust qualify for exploitation as energy source.

Depletionofuraniumresourcesisamatterofquality,notofquantity.

Energy cliff

In practice the richest and easiest accessible ores, those at the highest available thermodynamic quality, are always mined first, for these offer the highest return on investments. Consequently the world average energy quality of the available uranium resources are declining over time. When the thermodynamic quality of the yet to be exploited uranium occurencies will near zero, the uranium resources for the nuclear energy supply will get depleted. The gradual decline of the recoverable amount of net useful energy with decreasing thermodynamic quality of the natural uranium resources is here called theenergycliff.

Energy cliff over time

During the next decades the net energy from nuclear power will gradually decline, due to the depletion of high-quality uranium resources. If no new large high-quality resources will be discovered the net energy will decline to about zero when the lowest-grade known uranium re-sources are to be mined. The nuclear system then falls off the ‘energy cliff’. This could happen during the next 5-7 decades, within the lifetime of new nuclear build.

It should be noted that the energy cliff as phenomenon is not typically reserved for uranium as energy source. Similar developments are observable in the fossil fuel recovery from the crust: deeper wells at more remote and harsh locations are needed, the recovery of oil from tar sands consumes at least half of its energy content, recovery of gas from shales (fracking) consumes a substantial part of its energy content. Coal mining meets similar problems.

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The easy oil, gas and coal, having a high thermodynamic quality, are getting depleted. Exploi-tation of increasingly lower-quality resources is the trend.

New discoveries of uranium resources

New uranium deposits will likely be found in the future, when exploration continues. What mat-ters is the thermodynamic energy quality of the yet-to-be discovered deposits.The easiest discoverable and easiest accessible deposits are already known for decades. Based on currently available evidence the majority of the yet-to-be discovered uranium deposits may be of lower thermodynamic quality than similar deposits currently known, and consequently may lay closer to the energy cliff. A lower thermodynamic quality results not only from a lower grade, but also from other factors, such as: smaller ore body, greater depth below surface, less favourable geologic conditions and more refractory mineralogy.

Unconventional uranium resources

Vast amounts of uranium are known to be present in black shales, phosphate rock, lignite and coal. Due to the low grades, typically less than 0.1 gram per kilogram rock, extremely large amounts of the uraniferous deposits would have to be mined and processed. The energy consumed in the uranium extraction would push the nuclear energy system off the energy cliff.

Mineralogical barrier

In addition to the unfavourable effect of lower ore grades, another phenomenon greatly increases the energy input per kilogram recovered uranium. Below a certain uranium content the uranium atoms in a uraniferous rock do not form separate uranium mineral grains, but are dispersed in the matrix of the host rock. This implies that the whole mass of uraniferous rock has to be brought into solution to make possible the extraction of the uranium atoms from it. The consumption of chemicals and energy in this case is a factor 10-100 higher than the amounts needed for extraction from conventional ores, which contain separate uranium mineral grains which can be separated from the other minerals in the host rock by physical means, such as flotation. This phenomenon is called the mineralogical barrier.

Uranium from seawater

The optimistic view of the nuclear industry with regard to the possibilities of extraction of ura-nium from seawater, is based on laboratory-scale experiments, untried technology, unproven assumptions and a billion-fold extrapolation of a few experiments. The size of the installations required for recovery of uranium from seawater at a substantive scale would be measured in tens of kilometers. Such installations would have to be positioned in warm ocean currents, such as the Gulfstream, because recovery of uranium from seawater is only practically feasible at water temperatures exceeding 20 °C. The consumption of materials and energy would be prohibitive.

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10100 1 0.10


amount ofuranium

(million tonnes)

soft ores

hard ores

1.0

2.0 © Storm

world known recoverable uranium resources 2008

Figure 38-1. Known recoverable uranium resources of the world.Distribution of the known recoverable conventional uranium resources as function of decreasing ore

grade. The ore grade distribution shows that the resources are larger at lower grade, a common geologic

phenomenon of all metals in the earth’s crust. Below grades of 200-100 grams of uranium per tonne rock,

no economically recoverable resources are reported. Poorer ores tend to be harder to exploit, because of

more refractory mineralogy. Recovery of uranium from hard ores requires more useful energy than from

soft ores at the same ore grade. The known ore grade distribution of uranium exhibits a so-called bimodal

character, not a very common phenomenon in geology. At ore grades between 5-50 gram uranium per kg

rock only a few, small deposits are known.

10100 10

0.1


© Storm

net energyfrom uranium

as found in crust

Figure 38-2. Energy cliff.The net energy represented by 1 kg uranium as present in the earth’s crust declines with declining ore

grades, due to exponentially rising energy consumption per kilogram uranium with falling ore grades,

while the gross energy generated per kg recovered uranium has a fixed value. The green colored area

represents the ore grade domain within which the nuckear system has a positive energy balance. Below

a grade of 1 gram U per kg rock the net energy from nuclear power steeply falls to zero (red curve): the

energy cliff. The critical ore grade of the energy cliff, around 0.1 gram uranium per kg rock, turns out to

be independent of the assumed energy investments of the nuclear power plant. In the background of this

graph the ore grade distribution of the known uranium resources is given.

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10

100

1

0.1

© Storm

kg uraniumper tonne rock

year2070 20902010 2030 2050

scenario 2constant nuclear share2% world energy supply

scenario 1constant nuclearcapacity 370 GW

decliningore quality

Figure 38-3. Known uranium resources over time.Usually the easiest recoverable uranium resources are mined first, because these deliver the highest

return on investment. The easy uranium resources are easily discoverable, are at shallow depth, have high

ore grades and are mechanically and chemically easy for mining and milling. As a result of this common

practice the remaining uranium resources are less easy, meaning that the energy investments per kilogram

recovered uranium rises, even if the ore grade would remain flat. This graph is exclusively based on the

declining ore grade over time; other factors, such as depth and hardness of the ores are left aside.

2010

1

2

EROEIof

nuclear power

3

2030 2050 2070year

2090

energy sink

© Storm

Figure 38-4 Net energy from nuclear power: energy cliff over time.The energy return on energy investment (EROEI) is here defined as the ratio of the energy delivered to

grid over the energy investments, both measured over the full cradle-to-grave (c2g) period. At EROEI = 1

the nuclear energy system consumes as much useful energy as it produces. Below a value EROEI = 1 the

nuclear energy system becomes an energy sink, instead of an energy producer. This graph can be seen as

the energy cliff over time and is the synthesis of the energy cliff and ore grade, presented by Figure 38-

2, and the declining ore quality over time as presented by Figure 38-3. It turns out that the year of the

plunge into the energy sink does not depend on the assumed parameters of the nuclear reactor, but mainly

on the quality of the available uranium resources.

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i39

Energy and thermodynamics

Thermodynamics

The nuclear energy system is a technical means to unlock the potential energy embedded in uranium atoms and to convert it into electricity, useful energy, a process involving a number of energy conversions. Energy conversions are governed by the laws of thermodynamics. Thermodynamics is the science of energy conversions and lies at the base of all sciences. Consequently the generation of nuclear energy is subject to the laws of thermodynamics. Several basic notions are important in the assessment of nuclear power and the sustainability of the world economic system:• energy• First Law• spontaneous changes• entropy• Second Law

Energy

Energy is a basic and conserved physical quantity, which cannot be deduced from other physical quantities, Consequently energy is a starting point of thermodynamics. Energy can be defined as the entity making changes possible.

First Law

The First Law is the well-known law of energy conservation: energy cannot by destroyed, nor created from nothing; only energy conversions are possible.

Spontaneous changes

Some changes happen spontaneously, other don’t. A cup with hot tea cools down to the temperature of the surrounding air; a cup of cold tea never gets hotter by cooling down the surrounding air. A piece of charcoal (carbon) burns to hot carbon dioxide, but an amount of hot carbon dioxide never forms spontaneously a piece of pure carbon. Reheating the tea or reconversion of the carbon dioxide into carbon again is possible only by doing dedicated work.

Not all spontaneous processes will start spontaneously: sometimes a small amount of activation energy is needed to get the process going. For example one spark is needed to ignite any amount of oil, wether 1 gram or millions of tonnes: once started the spontaneous process continues until the last drop of oil has burned. The same holds true for fission of fissile uranium atoms: once started the chain eaction will go on as long as sufficient fissile material is available. An uncontrolled fission chain eaction results in a nuclear explosion. The function of a nuclear reactor is to keep the fission rate under control.

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When a change occurs, the total energy in the universe remains constant, according to the First Law. Spontaneous changes are always accompanied by a reduction of the quality of the involved amount of energy: during the change the energy quality is degraded to a more dispersed form. Spontaneous processes are consequences of the natural tendency of the universe towards greater entropy, a greater dispersion of matter and energy.The reversal of a spontaneous process, in many cases only theoretically possible, would require investment of useful energy and dedicated effort [more i40].

Examples of spontaneous processes are: the dispersion of CO2 from burning fuel into the atmosphere, the rusting of steel in the open air and the decay of dead organisms.

Entropy

Entropy may seem a somewhat elusive notion, but it is a key notion in thermodynamics.Entropyisameasureofdispersalofmatter,ofenergyandoforientedmovement.

In practice only entropy changes of a system can be observed. For understanding some basics of nuclear power and sustainable energy a semiquantitative approach of entropy changes is satisfactory: we only need to know if the entropy of a system increases or decreases by a given action or phenomenon [more i40].A rise of the entropy of a system means more dispersion of matter, energy and directional movement, or in other words: a loss of quality and usefulness of the observed system. For that reason entropy may be described in non-physical terms as a measure of ‘messanduselessness’. A decrease of the entropy of a system means less randomness and consequently a gain of quality and usefulness of the system.

Second Law

The Second Law of thermodynamics is one of the most basic laws of nature. It says that any spontaneous process in a given system will go in the direction of more dispersal of matter, energy and directional movement: to more entropy of the system.

In a systemwithoutmaterial exchangewith its surroundings any spontaneous processwillincreasetheentropy(disorder)ofthesystemanddecreaseitsqualityandusefulness.

A most important consequence of the Second Law with regard to nuclear energy generation is:The generation of an amount of useful energy from a mineral energy resource (fossil fuels, uranium) inextricably generates more disorder, more mess and more loss of quality (= more entropy) within the biosphere than can be compensated for by the produced amount of useful energy [more i41].

Potential energy

Potential energy is energy embodied in some kinds of matter. Fossil fuels contain potential energy, in the form of chemical energy, which is liberated as heat when the fuel is burned.Uranium contains potential energy embodied in the nuclei of the atoms of the metal, which is liberated as heat and radiation when the nuclei are fissioned.

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Useful energy

Useful energy is energy that can be used at will to attain an energy service: transport, lighting a room, cooking, running a computer, producing iron from iron ore, and so on. Useful energy is energy that flows in one direction, for example electricity flowing through a copper wire, heat that flows from a hot to a cold place, kinetic energy embodied in a spinning wheel. What is called the generation of energy is actually the conversion of potential energy into useful energy. A nuclear power station converts potential energy in uranium into heat and the heat partly into electricity.

Figure 39-01. Second LawRusting of a steel pole is a result of spontaneous processes, in accordance with the Second Law. When

left unattended long enough, the steel pole will end up as a pile of dust. The entropy of the steel of the

pole, the system in this case, has increased by the spontaneous process: the mess and uselessness of the

original amount of steel have increased. The amount of iron in the observed system has not changed: the

iron atoms of the original tube are still present in the pile of rust grains.

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Entropy

System and system boundaries

In thermodynamics a system is defined as the quantity of matter and space which is observed in the context of a given scientific study. The remainder of the world is called the surroundings of the system. To avoid ambiguities the boundaries of a given system should be accurately defined.

All human activities occur within the biosphere, a thin layer around the Earth in which life has developed and can exist. The biosphere is the only place where human life is possible. From a thermodynamic point of view it may be obvious to consider the biosphere as the surroundings of all human systems and activities. The biosphere in itself is a finite system, an observation with far-reaching consequences.

If we want, for example, to analyse the impact of nuclear power on the human environment, the complete nuclear process chain should be the observed system and the biosphere its surroundings.

Definition of entropy

Entropy is the key notion in understanding the Second Law and with this law of many basal phenomena of nature. The definition of entropy can be formulated in various ways, here we use the description:

Entropyisameasureofdispersalandrandomnessofmatter,ofenergyandoforientedmovement.Amorerandomdistributionofmatterandenergyinasystemmeansahigherentropyofthesystem.

This probabilistic approach of the notion entropy is based on the quantization of matter and energy. Matter consists of elementary particles, atoms and molecules, and energy transfer occurs in small discrete steps, called energy quanta. An example of energy quanta are photons: a photon is the smallest quantity of light.

Entropy changes

In practice we only observe entropy changes of a system. For understanding some basics of nuclear power and sustainable energy a semiquantitative approach of entropy changes satisfies: we only need to know if the entropy of a system increases or decreases by a given action or phenomenon. A rise of the entropy of a system means more randomness: more dispersion of matter, energy and directional movement, or in other words: a loss of quality and usefulness of the observed system. For that reason entropy may be described in non-physical terms as a measure of ‘messanduselessness’. An entropy reduction of a system means less randomness and a gain of quality and usefulness of the system.

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When a steel tube rusts and decays into a pile of brown grains, the mess and uselessness of the original amount of steel have increased, or in thermodynamic terms: the entropy of the system has increased. The amount of iron in the observed system has not changed: the iron atoms of the original tube are still present in the pile of rust grains.

The following phrase is a metaphor of an entropy increase as e result of a spontaneous process:Anyfoolcanpouracupofteaintotheocean,butathousandwisemencannotpullitoutagain.

Observable anthropogenic entropy effects in the biosphere

All human activities are occurring within the biosphere, so all entropy effects of the human activities remain within the biosphere. The biosphere is the only system in which human life is possible.A rise of the entropy of the biosphere caused by human activities manifests itself as deterioration of the environment and loss of quality of ecosystem services. In fact, all anthropogenic environmental problems are entropy effects. This is not difficult to recognize, for these are caused by dispersion of matter and energy and by degradation of the usefullness of ecosystem services. At the present conditions the netresult of the human activities is degradation of the quality of ecosystems, causing loss of functionality and loss of usefullness to humankind.

Examples of anthropogenic entropy effects are:• dispersion of CO2 and other human-made greenhouse gases throughout the atmosphere • pollution of air by dust, soot, acidifying and radioactive gases• pollution of ground water, rivers, lakes, sea, air and soil by anthropogenic chemicals • oil spills• destruction of ecosystems by mining• dispersion af radioactive materials into the air, water and soil• erosion of arable land, loss of topsoil, degradation and decline in soil fertility• washout of phosphate fertilizers into rivers and sea• desert forming by overgrazing of grasslands• decline of biodiversity• decline of fish populations in the sea• deforestation• loss of irreplaceable materials,such as platinum and phosphates• rising global temperatures by greenhouse gas emissions.Most of these entropy effects are irreversible on human timescales.

Ordered materials, functionality and entropy

Materials in the context of economy and society generally are processed materials, for example metals, medicines and plastics. These ordered materials have desired and predictable properties and a high usefullness for specific purposes. How well is a given material or piece of equipment suited to perform a given task, and what is the mean time between failures? These questions refer to the functionality and reliability of materials and constructions. Functionality has to do with the specific properties of a piece of equipment and the materials it is made from. Reliability has to do with the predictability of the behaviour of the equipment and materials under operational conditions of wear, stress and corrosion.Increasing the functionality and reliability of materials and machines is the opposite of a spontaneous process and is only possible by means of dedicated effort and investment of useful

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energy. Degradation of functionality and reliability, that means increase of the entropy of the system, is a spontaneous process.

The more specialistic the task, the higher the required quality standards of materials, design and craftsmanship for production of the material and/or object, and consequently the higher energy input. A higher functionality, or quality, requires a higher investment of useful energy and human skill. This observation follows directly from the Second Law.

Even the most reliable components will ultimately fail as a result of spontaneous processes. Lowering the chance of failure, requires higher quality standards of materials and dimensioning of each component. The chance of a failure can be reduced by maintenance and investment of useful energy, but cannot be eliminated. For that reason an inherent safe nuclear reactor is inherently impossible [more i15].

Fallacy of economic growth

The following view is a widespread fallacy:‘The economy has to grow to generate the economic means necessary to compensate for the

environmental problems.’

Environmental problems are observable consequences of anthropogenic entropy generation. History shows that economic growth invariably implies a growth of the consumption of energy and raw materials and consequently an ever increasing environmental deterioration.From the Second Law follows [more i41] that the generation of useful energy from mineral energy sources generates more entropy than can be compensated for by the corresponding amount of useful energy. Compensation of one unit entropy (environmental mess) generated in the past, a multiple of units of entropy would be generated today, irrevocably coupled to the generation of the required amount of useful energy.Besides, most anthropogenic entropy effects are irreversible as noted above.

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Consequences of the Second Law

Validity of the Second Law

The Second Law of thermodynamics is one of the most basic laws of nature. Up until this moment no phenomena have been observed in the known universe which would be in conflict with the Second Law, so the law is considered to be valid for all known phenomena in nature. The Second Law says that any spontaneous process in a given system will go in the direction of more dispersal of matter, energy and directional movement: to more entropy of the system.

Visibility of the consequences on global scale

Despite its basic importance the Second Law is rather invisible in most natural sciences and technologies. Usually natural phenomena and behaviour of technical systems can be explained in a way satisfactory for most purposes without using the somewhat elusive notions entropy and Second Law.

The reason why the notions entropy and the Second Law should play now a prominent part in environmental sciences is the scale of the human activities in the biosphere. Human behaviour has observable adverse effects on global scale, for example change of climate and decline of biodiversity. Human activities are not negligible anymore in comparison with the natural processes in the biosphere. Further expansion of human demand of resources and ecosystem services brings us in direct conflict with natural processes and ecosystems on global scale.

The magnitude of the human activities in relationship with the finite size of the biosphere, as a thermodynamic system, forces us to go to the basics of science and to apply the Second Law on environmental issues and sustainability of our society.

Principle of the Second Law

Each change in the universe is coupled to an energy conversion and an entropy effect. A basic formulation of the Second Law is: Witheverychangetheentropyoftheuniverseincreases.

To understand the effect of the Second Law in the context of nuclear power and sustainable energy a full comprehension of the notion entropy is not necessary.The Second Law can be formulated in different ways. Selfevidently all correct formulations are based on the same principle:

dispersionofmatterandrandomizingoforientedenergyflowsbyanyspontaneousprocess.

In respect of processes of everydays practice and in the context of nuclear power and sustainable energy the following formulation is useful:

Inasystemwithoutenergyinputfromtheoutsideandwithoutmaterialexchangewithitssurroundingsanyspontaneousprocesswillincreasetheentropy(randomnessofmatterand

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energy)ofthesystemanddecreaseitsqualityandusefulness.

Probability and the Second Law

In a given system, consisting of a certain amount of materials in a certain volume at a certain pressure and containing a certain amount of energy, the distribution of particles and energy quanta will end up in the most probable distribution by spontaneous processes. Examples are the dispersion of a scent in a closed room and the levelling of the temperatures in a closed room with a cup of hot tea.Any deviation from the most probable situation will require dedicated effort and useful (directional) energy. The farther the desirable situation deviates from the most probable situation, the more dedicated effort and useful energy is required to reach that situation. In other words: the more specific the properties of the desirable ordered material are, the less probable is the end situation from a probababilistic viewpoint and consequently the more useful energy has to be invested to fabricate the ordered material from raw materials.

Heat engines

Heat engines are machines for conversion of heat into mechanical and electric energy, such as steam and gas turbines and car engines. From the Second Law follows that heat cannot be converted fully into mechanical and electric energy. The heat generated in the heat source flows through the heat engine to the surrounding at a lower temperature. A part of this heat flow can be conveted into mechanical energy. The conversion efficiency is mainly determined by the temperature difference between the heat source and the surroundings of the heat engine. This context of the Second Law is the best known among technicians and scientists.

A nuclear power station is a heat engine with a nuclear heated boiler. Generally the net conversion efficiency is around 32-34%. That means that 66-68% of the generated heat in the nuclear reactor is discharged as waste heat into the environment.

Separation processes

Separation processes are a common and essential part of industrial activities needed for production of the ordered materials used in the economic system, such as steel, medicines, electronic components and prepared food.

A consequence of the Second Law with respect of separation processes is:• The separation of a mixture of different chemical species never goes to completion.

Consequently it is not possible to separate a mixture into its pure constituents without losses.

• The amount of useful energy required for separation increases with the number of chemical species in the mixture and with the desired purity of the separated constituents.

The limitations of separation processes has far reaching consequences for the potential of nuclear power [more i42, i43].

Coupled systems

An important consequence of the Second Law is that the conversion of a given amount of potential energy into useful energy, say by fission of 1 kg uranium, generates more entropy than can be compensated for by the generated amount of useful energy. More entropy means more

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mess and uselessness.

Lowering the entropy of a given amount of matter (here called system A), equivalent to an increase of the usefulness of the system, is only possible if simultaneously in another amount of matter (system B) the entropy increases with a larger amount: the sum of both entropy changes jointly is a net increase, in other words a net increase of mess and uselessness. The useful energy generated in system B makes possible the increased usefulness of system A. Systems A and B are thermodynamically coupled systems.An example of coupled systems is an electrolysis plant to produce aluminum as system A, powered by the electricity from a nuclear power station as system B.

Ordered materials: reliability and energy investments

How well is a given material or piece of equipment suited to perform a given task, and what is the mean time between failures? These questions refer to the functionality and reliability of materials and constructions. Functionality has to do with the specific properties of a piece of equipment and the materials it is made from. Reliability has to do with the predictability of the behaviour of the equipment and materials under operational conditions of wear, stress and corrosion.

Upgrading an amount of a raw material into a useful substance or a piece of equipment implies lowering the entropy of that amount of raw material. To produce useful materials and objects from raw materials as found in nature dedicated effort and energy is needed. An object is better useful when it is better suited to perform a specialistic task. The more specialistic the task, the higher the quality standards are required of materials, design and craftsmanship for production of the material or object, and consequently the higher energy input. A higher usefulness, or quality, requires higher investments of useful energy and human skill. This observation follows directly from the Second Law.

Mineral energy sources are not sustainable

Mineral energy resources – fossil fuels, uranium and deuterium/lithium for fusion – are recovered from the accessible part of the earth’s crust, within the biosphere. Burning fuels, fissioning uranium and fusing deuterium + tritium are basically spontaneous processes, once started, which can go on as long as fuel is available. The entropy generation inevitably coupled to the these spontaneous processes and the generation of useful energy from these sources, occurs within the biosphere.

From the Second Law follows that the generated amount of useful energy from mineral energy sources is insufficient to compensate for its coupled entropy generation, even if all useful energy would applied to that purpose. As a result the entropy of the biosphere increases constantly by using mineral energy sources. For that reason no mineral energy source can be sustainable, by definition. As the biosphere is a finite system, an unlimited increase of man-made entropy will irrevocably lead to environmental disasters, endangering human society [more i40].

Declining thermodynamic quality of mineral resources

A second effect accelerates the entropy generation associated with the energy production in the biosphere, even if the demand of useful energy would remain constant: the declining thermodynamic quality with time of the remaining mineral resources. Lower thermodynamic quality results in a higher entropy generation per unit delivered useful energy. The easiest

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reoverable resources are exploited first, so the remaining resources are harder to exploit. Harder means higher requirements of useful energy and ordered materials per unit recovered mineral.These developments are observable in the fossil fuel recovery from the crust: deeper wells at more remote and harsh locations are needed, the recovery of oil from tar sands consumes at least half of its energy content, recovery of gas from shales (fracking) consumes a substantial part of its energy content and cause extensive damage to ecosystems. Coal mining meets simi-lar problems. The average uranium ore grade declines and the the mining companies have to dig deeper. The easy oil, gas and coal, having a high thermodynamic quality, are getting deple-ted. Exploitation of increasingly lower-quality resources is the trend.

Sustainable energy supply has to be based on an energy source outside of the biosphere, so the associated entropy generation stays outside of the biosphere. Man has one: the sun [more i44].

Photosynthesis in the biosphere, spontaneous order from chaos?

Plants grow spontaneously. Via the photosynthesis carbondioxide from the air, water and dissolved minerals in the water are fixed into highly sophisticated biomolecules. From chaotic materials highly ordered materials with very specific properties are synthesized. As pointed out above ordered materials have low entropy. Apparently order from chaos in a spontaneous process. Is photosynthesis a violation of the Second Law?Of course not. The biosphere with its photosynthesis is thermodynamically coupled to the sun. The sun emits useful energy in a unidirectional flow, which green plants utilize to increase the usefulness of chaotic matter. The entropy generation on the sun is far greater than the entropy reduction in the biosphere, so the Second Law is obeyed.

Photosynthesis may seem a spontaneous process from a human point of view, for no human intervention is needed. From a thermodynamic viewpoint photosynthesis is the opposite of a spontaneous process, for it requires the input of high-quality directional energy (solar radiation) and proceeds under the influence of an ordering principle (DNA of the living cells).

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i42

Limitations of separation processes


Separation processes play a vital role in the process industry, especially in the nuclear energy system. The nuclear process chain starts with the extraction of uranium from its ore, a sequence of physical and chemical separation processes.Separation processes are based on chemical and physical distribution equilibria. These dynamic equilibria are governed by the laws of thermodynamics and never go to completion, as a consequence of the Second Law. For that reason it is impossible to separate a mixture of different chemical species into separate fractions without losses. Separation becomes more demanding, requiring more useful energy and specialistic materials and equipment, and goes less completely as:• more different kinds of species are present in the mixture,• the concentration of the desirable species in the mixture is/are lower,• the constituting species of the mixture are chemically and/or physically more alike,• the purity specifications of one or more of the fractions are more stringent.

Purification

Purification of a substance is based on separation processes, aimed at removal of contaminants from the substance. A higher purity means a lower concentration of contaminants. Extracting a species at a lower concentration requires more useful energy and is coupled to greater material losses. Higher purity means better predictable properties of a material. As pointed out above 100% pure materials are impossible. Purity specifications depend on the application of a material. Actually purity in the process industry is an economic notion.One of the many purifications performed in nuclear technology is the fabrication of Zircalloy, the clading material of nuclear fuel. Zircalloy is made of exceedingly pure zirconium, with a few percent of another very pure metal added. Zirconium as found in nature is always contaminated with hafnium, a highly undesirable element in nuclear cladding. So natural zirconium has to be purified, an intricate process requiring a high input of useful energy and auxiliary chemicals, because hafnium and zirconium are chemically much alike.

Extraction of uranium

Above observation means that the extraction of uranium from uranium-bearing rock, usually named mining and milling, consumes more energy per kilogram recovered uranium and goes less completely with decreasing ore grade. That implies that the recovery yield (the fraction of uranium present in the rock which is actually extracted) declines with declining ore grade. From rock containing 1 gram per kilogram rock some 95 % can be recovered. At a content of 0.1 g/kg less than 50% of the uranium present in the rock can be recovered, the other 50% are lost in the waste stream (mill tailings). This phenomenon greatly contributes to the phenomenon of the energy cliff [more i38].

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The specific energy consumption of the extraction of uranium, measured in energy units per kilogram recovered uranium, is determined by two variables: the dilution factor and the extraction yield. The dilution factor is proportional to the uranium content of the ore: to get hold of 1 kg uranium from ore at a grade of 1 kg U/tonne at least 1 tonne of rock has to be processed, from ore at a grade of 100 g U/tonne at least ten times as much rock has to be processed and at least ten times as much energy is consumed per kg recovered uranium.

On top of the dilution factor comes the declining recovery yield of the extraction process with declining ore grade, and consequently the specific energy consumption per kg recovered uranium rises steeply at low uranium ore grades. As the energy production per kg recovered uranium has a fixed value, the energy invetment of the uranium recovery surpasses the energy content at a given ore grade. This is called the energy cliff. The critical ore grade lies in the range of 0.1-0.2 gram uranium per kg rock, depending on the ore properties.

Of course the phenomenon of steeply rising energy investment per kg metal with declining ore grade is not typical for the recovery of uranium from the earth’s crust.

Enrichment of uranium

Natural uranium, at the isotopic composition as found in nature, contains 0.7% of the fissile uranium-235 atoms and 99.3% of the non-fissile uranium-238. For use as nuclear fuel the uranium has to be enriched in U-235 atoms. This involves a physical separation process, based on the slightly different masses of the U-238 and U-235 atoms, which is done by means of diffusion or ultracentrifuge plants. Due to the scantness of the physical differences between the two isotopes, a large number of separation steps are needed to enrich the uranium to the desirable isotopic composition of 2-5% U-238. As a result enrichment is a very energy-intensive process.It is not possible to extract all U-235 atoms from natural uranium, a consequence of the Second Law as pointed out above, Unavoidaby the enrichment process generates a large waste stream of depleted uranium with a lower content of U-235 atoms than natural uranium of 0.2-0.3%.

Reprocessing

Reprocessing of spent nuclear fuel is an intricate sequence of separation processes, aimed at the recovery of plutonium and unused uranium from spent fuel.Reprocessing is a pivotal process in several advanced nuclear concepts, such as closed-cycle reactors, breeders, partitioning + transmutation of long-lived radionuclides and nuclear fusion [more i30]. Separation of the involved highly radioactive mixtures, containing dozens of kinds of radionuclides, into pure fractions is impossible, as follows from the Second Law. The separation losses increase with higher radiation levels, due to deterioration of the separation chemicals and equipment, and with a higher number of chemical constituents.

One consequence of the inherently incomplete separation is that all nuclear concepts relying on 100% separation efficiency are doomed to fail.

Another consequence is that a reprocessing plant generates large waste streams, which are larger and more hazardous as the radioactivity of the spent fuel is higher.

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addition ofkerosene phase

uranium ionsin water phase

establishment ofdistribution equilibrium

removal of aqueous phaseuranium lost to waste

kerosene phaseto next process

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Figure 42-1. Extraction of uranium from a solution.To recover uranium from its ore, the rock is ground to a fine powder. By means of chemicals the uranium

atoms are dissolved as ions in a watery solution, together with some other elements from the host rock.

Then a special mixture of kerosene and chemicals is added in which the uranium ions better dissolve than

in the water phase. After some time a distribution equilibrium is established, when the number of uranium

ions diffusing from the water phase to the kerosene phase equals the number diffusing in the opposite

direction. When the two liquid phases are decanted, inevitably a part of the original amount of uranium

ions are left in the water phase and are lost in the waste stream.

10100 1 0.10

gram uranium per kg rock

extractionyield

100% © Storm

Figure 42-2. Extraction yield of uranium from ore.Maximum attainable extraction yield (also named recovery yield) of uranium from its ore, as function of

the uranium content of the ore. The yield is defined as the actually recovered fraction of the uranium

as present in the original rock. In practice the yields are generally lower than in this diagram. The world

averaged uranium content of the currently exploited ores is 0.5-1 gram uranium per kg rock.

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10100 1 0.10

grams uranium per kg rock

10

energy consumptionper kg recovered uranium

(arbitrary energy units)

© Storm

dilutionfactor

yieldon top of

dilution factor

Figure 42-3. Specific energy consumption of the recovery of uranium from ore.The dilution factor is the relationship between ore grade and energy investment per kg recovered uranium

(green dotted line). On top of this comes the effect of the recovery yield, which declines with declining

ore grade. A lower yield means that relatively more ore has to be processed to obtain the same amount of

uranium and consequently more energy is needed.

enrichmentprocess

natural uranium

depleted uranium

enriched uranium1.00 kg

feed

waste

product

3.3% = 33 g U-235

5.08 kg

6.08 kg

0,2% = 10.2 g U-235

0.71% = 43.2 g U-235

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Figure 42-4. Isotopic enrichment of uranium, a physical separation.In an enrichment plant natural uranium is split up into two fractions: enriched uranium containing 2-5%

U-238 and depleted uranium containing 0.2-0.3% U-235; in this symbolic diagram 3.3% respectively 0.2%.

In practice the U-235 atoms are randomly dispersed between the U-238 atoms. To produce nearly pure

uranium-235 (weapons-grade) a much larger amount of natural uranium has to be processed, generating

a massive waste stream of depleted uranium.

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gaseous effluents

liquid effluents

volatile nuclides

dismantlingwastes

solids glassliquids

plutonium

uranium



fission products

actinides

H-3 C-14I-129


activation products

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spent fuel

Figure 42-5. Outline of reprocessing of spent nuclear fuel.Reprocessing is an intricate sequence of separation processes, aimed at the recovery of newly formed

plutonium and remaining uranium from spent nuclear fuel. Due to the inherently incomplete separation, a

part of the uranium and plutonium end up in the waste streams, and the recovered uranium and plutonium

are contaminated with other nuclides. Purification of the uranium and plutonium generates large waste

streams, as a consequence of the high purity specifications of the two metals.

The other radioactive (and non-radioactive) consituents of spent fuel are distributed over large

volumes of solid and liquid waste. Gaseous and volatile radionuclides are set free from the spent fuel

during the first steps of the reprocessing sequence, are not retained and are released into the human

environment. In addition the waste streams originating in the last steps of the separation and purification

processes are released into the human environment. Inevitably these waste streams contain all kinds of

radionuclides, those with high water-solubility in high concentrations, those with low water-solubility in

low concentrations. For above reasons reprocessing is an extremely polluting process.

Virtually nothing has been published on the discharges of non-radioactive pollutants, especially greenhouse

gases, by reprocessing plants. From a chemical point of view it seems unlikely that reprocessing would

notemit greenhouse gases other than CO2. So the contribution of reprocessing to the nuclear emission of

CO2-equivalents remains a well-kept secret.

The volumes of the decommissioning and dismantling waste of a reprocessing plant may amount to

hundreds of thousands cubic meters. This waste stream is never mentioned by the nuclear industry.

Unavoidably a significant part of this future radioactive waste stream will end up uncontrollably in the

human environment.

The cost of decommissioning and dismantling of the reprocessing plant at Sellafield (UK) is estimated at

some €100bn, more than the total cost of the American Apollo program, in €(2010), which resulted in the

landing of six crews on the Moon (1969-1972). These preliminary cost estimates, which most likely will

turn out to be too low, are an ominous indication of the unheard scale of decommissioning and dismantling

a eprocessing plant.

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i43

Nuclear power and the Second Law

Chemical pollution A nuclear reactor is not a stand-alone system: nuclear power is only possible by means of a sequence of conventional industrial processes [more i12]. As any process are these nuclear-related processes amenable to the Second Law. As a consequence releases of all chemicals involved in these industrial processes into the environment are unavoidable. No chemical plant can be leak-proof.

The nuclear reactor is the only part of the nuclear system that does not emit CO2, all other parts do. The CO2 originates from the combustion of fossil fuels to power the industrial processes and from chemical reactions, for example the production of concrete and of steel from iron ore. The specific CO2 emissions of the nuclear chain are rising and will surpass that of fossil fuels within the lifetime of new nuclear build. The rise is caused by the decreasing thermodynamical quality of the yet available uranium resources over time, which in turn is a consequence of the Second Law [more i05, i38]

In the front-end processes, the production of enriched nuclear fuel from uranium ore, massive amounts of fluorine and chlorine and their compounds are consumed [more i07, i13]. The most potent greenhouse gases known are compounds of fluorine and chlorine. Emissions of potent greenhouse gases by the nuclear energy seem not only possible, but seem likely. Emissions of greenhouse gases and releases of other chemical pollution by nuclear-related industries are a well-kept secret. Nopublisheddatadoesnotequal‘noemission’.

Radioctive pollution

Self-evidently radioactive substances are also chemical substances,the only difference with common chemicals is the presence of radioactive isotopes. Radioactive and non-radioactive isotopes are chemically identical. As pointed out above massive amounts of chemicals are being used in the nuclear process chain [more i13]. Inevitably a fraction of these chemicals are discharged into the environment, as a consequence of the Second Law, and with these sunstances radioactivity is being released into the environment.

In the nuclear energy system massive amounts of radioactivity are mobilized and generated [more i08], starting with the extraction of uranium from the earth’s crust. The natural radioactivity, which in itself is far from harmless, is in the reactor multiplied with a factor billion. An appreciable part of this human-made radioactivity is released into the environment, partly intentionally, partly due to technical imperfections and sometimes as a result of accidents. In all cases the Second Law is playing an important role. The chance of large accidents increases with time, due to deteriorating storage containers and facilities, a direct consequence of the Second Law.Radioactive emissions are generally concealed, or are played down as ‘harmless’ by the nuclear

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industry and associated institutions if disclosed nevertheless.Even emissions of radioactive materials classified as ‘weakly’ radiotoxic turn out to be harmful for people living in the neighbourhood of nuclear power stations. Not to speak of the massive radioactive contaminations after large accidents, such as Chernobyl and Fukushima [more i21].

Thermodynamic quality of uranium ores

Uranium-bearing rocks, in some cases called uranium ores, are present in the earth’s crust in different appearances and at widely different properties. Rocks with the highest content of uranium are the rarest, rocks with lower contents are much more widespread. This common geologic phenomenon, valid for almost all metals in the crust, results in a well-known distribution of the uranium resources: more uranium is present the lower its content in geologic formations.This grade distrbution is in itself a consequence of the Second Law during the history of the rock forming.From the Second Law follows that the energy investment per mass unit of extracted uranium increases exponentially with declining ore grade of the deposits from which the uranium is extracted: the energy cliff [more i38].


Separation processes play a vital role in the nuclear energy system, in the once-through mode and the more so in an envisioned closed-cycle mode. Separation processes are governed by the Second Law. As separation processes never go to completion, it is impossible to separate a mixture of different chemical species into separate fractions without losses [more i42].

ExtractionofuraniumThe nuclear process chain starts with the extraction of uranium from its ore, by means of a sequence of physical and chemical separation processes. As a consequence of the inherent limitations of separation processes the extraction of uranium from uranium-bearing rock consumes more energy per kilogram recovered uranium and goes less completely with decreasing ore grade. This phenomenon comes on top of the dilution factor. Jointly both factors are the cause of the energy cliff [more i38 and i42].

ReprocessingReprocessing of spent nuclear fuel is a pivotal process in a number of advanced nuclear concepts. Separation of highly radioactive mixtures, containing dozens of radionuclides, into 100% pure fractions is impossible, as noted above. As a consequence all nuclear concepts relying on a 100% separation efficiency are doomed to fail [more i30 and i42].

Inherently safe nuclear power is inherently impossible

The nuclear industry strongly suggests that nuclear power is inherently safe with inherently safe nuclear reactors. Nuclear reactors are part of an intricate system of industrial processes and activities, so even with inherently safe reactors nuclear power is not necessarily safe [more i14 and i15].Inherently safe means that on no condition an accident or unwanted event can occur in a technical a system and would imply the availability of fail-safe materials, fail-safe design, fail-safe construction and maintenance and fail-safe human behaviour. Inherently safe nuclear reactors exist only in cyberspace, because this concept would imply the availability of 100% perfect materials and 100% perfect separation processes. Both conditions cannot be complied with, as follows from the Second Law [more i42]. Human behaviour is evidently not 100%

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predictable. The conclusion is that inherently safe nuclear reactors are inherently impossible, let alone the nuclear energy system as a whole.

Latent entropy

From the Second Law follows that the mess and uselessness (entropy) of the biosphere increases by use of a mineral energy source, i.c. uranium, to such an extent that the full amount of the generated useful energy is by far insufficient to compensate for the deterioration of the biosphere caused by the energy generation [more i40 and i41].An important difference between fossil fuels and nuclear power as regards this observation is the way the entropy generation becomes observable. A part of the entropy generation associated with the extraction of mineral energy carriers is instantly visible as disturbances of ecosystems in the mining areas, dispersal of dust, contamination of groundwater and soil by chemicals, etcetera. The difference concerns the entropy generation associated with the conversion of the potential energy embodied in the mineral energy carriers into useful energy. When fossil fuels are burned, the combustion products and waste heat are instantly released: matter and energy are dispersed into the environment and the entropy of the biosphere rises maximally.

When uranium is fissioned the dozens of different kinds of fission products and radionuclides stay localised inside the spent fuel elements. A part of the fission entropy becomes manifest outside of the nuclear system, as waste heat, discharges of radionuclides into the environment and as radiation damage to materials and living organsms in the vicinity of the reactor. The fission products confined in the spent fuel elements inevitably will spread into the environment when nothing is done to prevent that. Then the fission entropy becomes manifest in its full size: dispersal of tens of different kinds of radionuclides, the spread of nuclear radiation and the damage to materials and living organisms in the biosphere caused by radiation. In every respect that would mean a maximum rise of mess and uselessness.Only by dedicated effort we can prevent the dispersal of the main part of the fission products and radioactivity generated in the nuclear reactor, by appropiate packing the radioactive wastes and by isolating it from the biosphere as best as possible [more i11]. At the moment of its generation, the main part of the fission entropy may be considered latent entropy. The longer we postpone adequate treatment of the nuclear waste, the more latent entropy will turn into actual entropy of the human environment.The dedicated effort to prevent this disastrous scenario will require massive investments of ordered materials, useful energy and human skill: this is the energy debt [more i16].

Materials specifications

The more specialistic the task, the higher the required quality standards of materials, design and craftsmanship for production of the material and/or object. A higher quality requires a higher investment of useful energy and human skill. This observation follows directly from the Second Law [more i40]. In nuclear technology exceedingly high quality specifications and high degrees of predictability of the behaviour of materials and equipment are required, consequently nuclear-grade constructions are extremely energy-intensive.

Advanced nuclear concepts

Advanced concepts of nuclear power generation are the uranium-plutonium breeder, the thorium-uranium breeder and partitioning & transmutation of long-lived radionuclides. Two technical achievements are a conditio sine qua non for materialization of each of these concepts:

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• separation of complicated mixtures of radionuclides into pure fractions without losses,• production of materials and machines with 100% predictable properties and behaviour. Separation and purification processes are governed by the Second Law, which implies that both suppositions are impossible. From this observation follows that the advanced nuclear power concepts are doomed to fail in practice, as has been proved by experiences during the past 50 years, though, and consequently can exist only in cyberspace [more i30. i31, i42].

Nuclear power cannot be sustainable

Uranium is a mineral energy source recovered from the upper layers of the earth’s crust, in fact within biosphere. As a consequence the entropy generation inevitably coupled to the generation of useful energy by fissioning uranium, occurs within the biosphere. Effects of increasing entropy within the biosphere always mean loss of quality of the human environment. A major part of the nuclear entropy is the generation and dispersion of radioactivity. Inevitably people are exposed to radioactivity, inflicting serious harm [more i41].From the Second Law follows that the generated amount of useful energy from any mineral energy source is insufficient to compensate for its coupled entropy generation, even if all useful energy would applied to that purpose. As a result, by using uranium the entropy of the biosphere increases constantly, which means increasing damage and deterioration. For that reason fission power is not sustainable, nor is any other mineral energy source. Genuinely sustainable energy generation is only possible if based on solar energy [more i44].

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i44

Zero entropy energy, ZEE

Physical sustainability criteria

The qualification ‘sustainable’ has different connotations: economic, physical, cultural. From a physical viewpoint a sustainable energy supply system should comply with three conditions:• lasting for indefinite periods of time,• without contributing to the entropy of the biosphere,• capacity potentially sufficient to meet the world energy demand.

Constant flow and constant quality

From the Second Law follows that a sustainable energy supply is not possible if based on mineral energy resources from within the biosphere, for reason of the finite size of the biosphere as system and consequently the declining thermodynamic quality of mineral energy resources as more of these resources have been consumed [more i41]. As a consequence the energy consumption of the extraction per unit useful energy rises with time at an increasing rate. Even if the final energy consuption would remain constant, the total energy consumption including extraction energy and losses, would rise exponentially.A constant flow and constant quality of high-quality energy which can be converted into useful energy with low losses has to be based on a stable energy source outside of the biosphere. Fortunately man has such an energy source at his disposal: a reliable nuclear fusion reactor at a distance of 150 million kilometers and operating for free for the next several billions of years. With a solar-based system human society will mimic the biosphere itself: life on Earth proved to be sustainable for hundreds of millions of years, without energy sources from within the biosphere. On the contrary, fossil fuels are fixed solar energy from eons ago.

No contribution to the entropy of the biosphere

This condition is inextricably connected with the first condition of constant flow and constant quality. Prerequisite for an energy supply which can be sustained for indefinite periods of time is that the useful energy generation does not contribute to the entropy increase of the biosphere, to prevent devastation of too many and too large ecosystem services of the biosphere [more i40]. Serious damage to ecosystem services might turn vast area’s into inhabitable regions.

From the Second Law follows that any sustainable energy supply complying with the second condition is possible only if based on an energy source outside of the biosphere, i.c. the sun. The entropy coupled to the generation of solar radiation remains in space, so the biosphere receives high-quality energy just about entropy-free: zero-entropy energy, ZEE. Basically the entropy generation associated with conversion of solar energy into useful energy is a fraction of the entropy reduction possible with the generated useful energy. Implementation of a ZEE system might result in a net entropy reduction of the human evironment and consequently an increase of usefulness of it. A ZEE system is a conditio sine qua non for a sustainable economic system, although it is not the only condition.

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A ZEE supply system for the world economic system must be based on technologies harvesting solar energy, directly or indirectly, e.g. by wind turbines, photovoltaic (PV) panels and concentrated solar power (CSP) systems. With a ZEE system human society will be able to mimic life on earth: the creation of ordered materials out of randomly dispersed substances for free.

Potential capacity

The joint capacity of renewable energy sources (e.g. wind, photovoltaics, concentrated solar power, biomass), though not infinite, is amply sufficient to meet the world energy demand. Evidently unrestrained growth of the economic system, implying unrestrained growth of the consumption of useful energy and raw materials, is impossible because of the finite size of the biosphere. This observation sets also limits to the world population.

Large areas are involved in harvesting solar energy, due to the low energy density of solar energy. To meet the final energy demand of the year 2010. A few figures may illustrate the potential of a ZEE system. Each of the following scenarios, based on currently proved and operational technology, would be able to meet the world’s final energy demand of 2010.1 Offshore wind parks of 5.25 million turbines of 5 MW each, spread over an area of 2.6

million square kliometers, surface footprint some 525 km2.2 Onshore wind parks of 6.66 million turbines of 5 MW each, spread over an area of 3.3 million

square kliometers, surface footprint some 13300 km2.3 Photovoltaic parks in desert regions, occupied area around 450 000 km2.4 Photovoltaic parks in temperate regions (comparable to UK, Germany), occupied area

around 950 000 km2. A substantial part of this area, perhaps one half of it, could be roof-mounted. World built-on area is some 2 million km2.

A mix of these techniques is obvious, combined with other techniques, such as concentrated solar power, hydro power and biomass. Energy efficiency improvements might reduce the demand by 10-40%, without compomizing comfort. Biomass could be used most efficiently as chemical feedstock, rather than as fuel. A major part of the electricity generated in above scenarios is assumed to be converted into hydrogen, for energy storage, as chemical feedstock (e.g. steel production) and as fuel for transport.

power: electricity &mechanical energy

heat

ordered materials

ener

gy s

ervi

ces

© Storm

Figure 44-1. Energy services

Symbolic representation of the main groups of the energy services needed to run the world economic

system: heat (space heating, industrial process heat), ordered materials from raw materials (e.g. steel

from iron ore) and power (e.g. electricity for lighting, transport, computers, and mechanical energy).

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presenteconomicsystem

accessible partof the earth’s crust

consumer goods+ energy services

biosphere

rawmaterialsentropy

mineralenergy

resources

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Figure 44-2

Symbolic ourline of our present economic system, based on mineral energy resources. The economic system

is a partial system of the biosphere. All materials and energy resources are extracted from the accessible

part of the earth’s crust and will return into the biosphere sooner or later. The entropy associated with the

generation of useful energy from the mineral energy resources stays within the biosphere and becomes

manifest as deterioration of ecosystem services (increasing mess and uselessness). The net result of

the economic activities is an increase of the entropy of the biosphere, because the entropy reduction

acchievable with the generated useful energy is much smaller than the entropy increase.

ZEESZEE

accessible partof the earth’s crust

consumer goods+ energy services

biosphere

rawmaterials

entropy sun

© Storm

Figure 44-3

Outline of the economic system based on zero-entropy energy supply (ZEE). The entropy generation

associated with the generation of the high-quality energy (solar radiation) reaching the biosphere stays

outside of the biosphere. The economic system can perform as a (nearly) zero-entropy economic system

(ZEES) in the respect that the entropy reduction can by larger than the entropy generation by the economic

system, depending on the way the zero-entropy energy is being utilized.

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i45

Reliance on models

Uncertainties in dose estimates

In official publications the radiation doses to individuals near nuclear power stations are invariably very low. These values are estimates and are not based on measurements. How these estimates are derived is not widely understood by scientists, and not at all by members of the public.The methodology is very complicated as it based on at least four kinds of computer models in sequence:• Models for the generation of fission and activation products in reactor cores. The emission data published by utilities are derived from these models.• Environmental transport models for radionuclides, including weather models.• Human metabolism models to estimate radionuclide uptake, retention and excretion.• Dose models which estimate radiation doses from internally retained radionuclides.

Each model has its inherent limitations so the result of each model has an uncertainty range. The uncertainties of each model have to be treated together to gain an idea of the overall uncertainty in the final dose estimate. Further uncertainties are introduced by ‘unconservative’ radiation weighting factors, dose rate reduction factors, and tissue weighting factors in the official models. The cumulative uncertainty in dose estimates could be very large.

Uncertainties in risk estimates

Risk models are used to estimate the likely level of cancers. The risk models have their inherent imperfections and uncertainties as well as the dose estimate models. The current official risk models are mainly based on studies of the Japanese survivors of the nuclear bombs in 1945. How reliable are the official risk models? Uncertainties are introduced by a number of factors, such as: • The Japanese bomb survivor study was started five years after the bomb blasts, so the deaths in the first five years were not counted.• The risks estimated from a sudden puls of gamma rays and high-energy neutrons are not applicable to environmental releases which result in chronic, slow, internal exposures to often low-range beta radiation, from biologically reactive radionuclides, such as tritium and carbon-14, but also from low-gamma alpha-emitting radionuclides.• Application to adults only.• Application of age and gender-averaged risks.• Arbitrarely halving the risks to take account of cell studies suggesting lower risks from low doses and low dose rates.

Troublesome detection of radionuclides

An impediment for sound health risks assessments is the fact that a number of dangerous radionuclides are hard to detect with commonly used radiation counters.

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As a result of the difficult detectability, severe radioactive contamination with these radionuclides may escape notice during prolonged periods. Not every spill or release contains ‘marker’ nuclides which are easily detectable, such as cesium-137. Examples of ‘unnoticed’ releases are the routine releases of nuclear power plants under nominal conditions [more i19]. For that reason it would be advisable to check on regular occasions food and drinking water on the presence of those troublesome radionuclides, even if no direct threat seems apparent. Risk estimates based on models likely will not come up to the mark.

Inherently limited significance of models

Any model in physics, economics or other field, inevitably has two kinds of limitations: inherent limitations and the specific limitations resulting from the choice of input data: constants, variables and other data.

InherentlimitationsA model is a simplified description of the reality, the practice, and is based on a number of axioms and assumptions. Models are widely used in science to describe specified phenomena in nature and to build a theory wich enables scientists to predict the occurrence of such phenomena under conditions different from the investigated ones. As a result of the simplification of the reality a model is only valid within specific system boundaries and has a limited application range. The wider the system boundaries of a model, the more complicated its structure.As a well-know scientist put it:

‘If empirical observation is incompatible with a model, the model must be trashed or amended, even

if it is conceptual beautiful or mathemathecally convenient.’

Two examples of scientific models used in chemistry may illustrate this statement. The simple model of atoms and molecules formulated by Dalton in the 19th century is able to describe some basic chemical phenomena. To explain why water has the formula H2O and not H3O and to predict chemical compounds not yet found, one needs the greatly more complicated atom model of Bohr. However, not all chemical phenomena can be explained by the Bohr model.

Specificlimitations:thechoiceofinputdataThe results of an investigation by means of a model are determined by the input data, such as physical constants, variables and properties of the entities of the model. How reliable are the axioms the model is based on and the input data? Are they experimentally verified and are they widely accepted by the scientific community? How large are the uncertainty ranges of the numerical input data and how do these uncertainties propagate into the results? How sure can we be that the investigator’s choices of the input data of his model were not outdated, or biased, wittingly or unwittingly?

FlexibilityFrom a scientific/mathematic viewpoint the radiological models seem rigid: once formulated, always and everywhere valid. Conspiciously the radiological models turn out to be flexible under economic pressure, as is proved by the recent relaxation of authorized radioactivity standards for drinking water in the USA and the relaxation of exposure standards in Japan after the Fukushima disaster.

Why not start from empirical evidence?

Which assumptions form the basis of the currently used radiological models? Which phenomena are included in the models and which are not?

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What was the original purpose of the models? To estimate the acute radiological risks for military personel in wartime, or to estimate the health risks for the public posed by chronic exposure to a number of radionuclides from civilian nuclear power?

More than ever the time has come to base health risk estimates on published and verifiable empirical facts, not on computer models originating from the closed nuclear industrial complex and based on outdated secret data. Epidemiologic studies in Germany anf France proved that the existing exposure and health risk models are unable to explain the empirical observations of that study, so the models must be revised.

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How indispensable is nuclear power?

Promoted image

The image of nuclear power – clean, cheap, safe, secure – rests on promises and concepts from the 1950s and 1960s, which turned out to be unfeasible decades ago. Evidently technology advances, but technology never can circumvent the basic laws of nature [more i43].At present the promotion of nuclear power is focused on climate change - nuclear power would be CO2-free - and on energy security. Safety is temporarily a less emphatic item after the Fukushima disaster.

Cheap

The qualification ‘cheap’ is not often used anymore. Financial aspects of nuclear power are not addressed here. Disguised are the enormous costs to be paid in the future, when nuclear power plants and reprocessing plants are to be decommissioned and dismantled and when geologic repositories are to be built: the energy debt [more i16].

Climate change

At present the nuclear share of the world energy supply is 1.9%, and declining. Even if nuclear power would be CO2 free, which it is not, then the reduction of the human CO2 emission could not be more than 1.9%. In the most optimistic scenarios of the so-called ‘nuclear renaissance’ the nuclear share would be no higher than 3-4% of the world energy supply by the year 2050.

The specific CO2 emission of nuclear power proves to be in the range of 80-130 grams CO2 per kilowatt-hour, if all industrial acivities directly related to the operation of a nuclear power plant are taken into account. This figure, about ten times higher than the figure cited by the nuclear indutry, is valid at the present conditions and will rise with time, due to the declining thermodynamic quality of the yet available uranium resources: the CO2 trap [more i05, i38].

With improvement of the energy efficiency of economic activities energy reductions of 20-40% are possible without sacrificing comfort. This would result to an reduction of 20-40% of the CO2 emission, at a fraction of the costs of the nuclear contribution of less than 1.9%.

Emissions of greenhouse gases other than CO2 are kept secret by the nuclear industry, so an equivalent comparison with other energy systems is not possible [more i05, i13].

Clean and safe

Emissions and discharges of other non-radioactive chemicals into the environment are kept secret by the nuclear industry [more i05, i13] so comparison on this issue with other energy systems is not possible.The emissions and discharges of radioactivity into the human environment are extensive, but

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are systematically downplayed [more i17, i23].Safety of nuclear power has within the nuclear world another connotation than in the public domain [more i14, i15].

Energy security

Nuclear power is based on a mineral energy source: uranium. Just like any other mineral energy source, the easiest recoverable resources are consumed first. The investments of materials and energy required per kilogram recovered uranium will increase with time due to declining thermodynamic quality of the remaining uranium resources. Consequently the net energy production by the nuclear energy system will decline over time and falls to zero when uranium has to be recovered from resources below a certain uranium ore grade: the energy cliff [more i38].Advanced nuclear reactor systems which could fission a much larger fraction of uranium than the currently operating reactors will remain possible only in cyberspace [more i30].

Sustainable energy

The sole solution of the energy and climate problematique lies at our feet: the utilisation of the full potential of energy conservation combined with the transition to the single genuinely sustainable energy source man has at its disposal: a reliable fusion reactor at a distance of 150 million kilometers. This nuclear reactor delivers its high-quality energy for free and will do so for the next billions of years.

A sustainable energy supply, which can last indefinitively, is possible only if based on energy sources outside of the biosphere. From the Second Law follows that the use of energy sources from within the biosphere, the mineral sources fossil fuels, fission and fusion, unavoidably results in an ever-growing environmental mess [more i41, i43]. The biosphere as we know it with all its forms of life, owes its existence to an energy source outside of the biosphere, the sun. Why should humankind not mimic the non-human part of the biosphere?

Zero-entropy energy, ZEE

Solar energy can be utilized directy by means of photovoltaics (PV), concentrated solar power (CSP) and heat collectors, and indirectly by means of wind turbines, hydro power and wave power. Based on these technologies a zero-entropy energy (ZEE) supply can be realized, with which humankind would be able to reverse the ongoing deterioration of the biosphere by human activities [more i44].Some characteristics of a ZEE system are:• abundant (though not infinite capacity)• constant flow (not counting short-term fluctuations)• high and constant quality• freely accessible to everyone• proven technology, with considerable potential of improvements• cheap, counted over the system lifetime• clean: emission of greenhouse gases very limited and only during construction• clean: no discharges of hazardous chemicals• all materials recyclable• safe: no large accidents possible with irreversible consequences• fast to implement• each continent can be self-supporting, contributing greatly to geopolitical stability

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• does not generate radioactivity.

It might be worthwile to analyze how vast the areas are which are affected by nuclear power: the regions, lakes, rivers, and seas irreversibly contaminated by radioactivity as a result of accidents but also of nominal operation [more i18, i21]. How would the nuclear-affected area compare to the area occupied (reversibly) by renewables [more i44] supplying the same share of the world energy supply as the present nuclear share (1.9%)?

Nuclear power is a dead-end road

Summarizing the observations resulting from an elaborate analysis of the nuclear energy system one has to conclude that someday nuclear power will fall off the energy cliff, will run aground in the CO2 trap and energy debt and will cause unheard disasters in densily inhabitated regions. These observations follow from the basic laws of nature, especially the Second Law of thermodynamics [more i38, i05, i16, i21, i43]. Advanced technology will never be able to circumvent these laws.Nuclear power is absorbing energy, materials, human skill and economic means at an increasing rate, blocking the way to a sustainable energy supply system. Important is to recognize the misconeptions and fallacies which help to maintain the believe in nuclear power. The Second Law is an objective ruler to assess the feasibility of technical concepts.

© Storm

construction construction

time

time

ZEE

entropyincrease

entropyincrease

c2gentropygeneration

c2gentropyreductionpotential

entropyreduction

?

operationoperation

nuclear energy

cradle-to-grave period cradle-to-grave period

dismantling+ wastemanagement

dismantling+ wastemanagement

Figuur 46-1. Cradle-to-grave entropy generation of nuclear power and solar power.

Entropy generation of nuclear power and solar power over the entire cradle-to-grave (c2g) periods of the

energy systems. ZEE = zero-entropy energy: the renewable energy systems based on solar energy, directly

and indirectly. Entropy is a measure of dispersion of matter and energy: higher entropy, higher dispersion.

Higher entropy of the biosphere means more mess, more damage to the biosphere. Higher entropy of a

given amount of matter means a higher degree of uselessness [more i39, i40, i41].

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Is nuclear power obsolete?

Nuclear technology is generally considered to be a high-grade and advanced technology. But does this qualification imply that nuclear power as a civil energy source can be called also high-grade and advanced? The state of a technology is not the same as its usefulness for societal implementation.

A technical commodity becomes obsolete when other commodoties are available which are better suited for the same task. The task at issue is the delivery of useful energy to the consumer with the least possible burden to the economic system and with the least possible environmental burden. Nuclear power has a number of specific features which should be taken into account in the comparison with other energy systems:

• radioactive releases into the environment at an increasing rate; radioactive discharges are cumulative [more i17],

• radioactive contamination of hundreds of thousands of square kilometers [more i18, i19, i21],

• growing risk of very large accidents [more i21],• rising specific CO2 emission over time, surpassing that of fossil fuels by 2050-2070: the CO2

trap [more i05],• decreasing net energy production over time: the energy cliff [more i38],• extremely long cradle-to-grave periods of 100-150 years [more i12, i16],• systematic postponement of very large, but unavoidable energy investments to the future:

the energy debt, which is growing with time [more i16],• increasing deterioration of the environment by nuclear-related activities [more i43],• large and growing specific consumption of materials and chemicals per unit delivered useful

energy [more i13].• potential contribution of about 2% at best to the world energy supply by 2050 [more i28].• evidence of the nuclear power adoption curve [more i29].

Nuclear technology cannot be developed to an advanced level high enough to prevent above noted drawbacks, because no technology can circumvent the Second Law. The question at issue is wether nuclear power has been surpassed by other technical means to generate useful energy with better and larger possibilities. From the Second Law follows that a permanently sustainable energy system, without the specific drawbacks and limitations of nuclear power, is only possible if based on an energy outside of the biosphere. Luckily we have one: the sun. With proven technology it is possible to construct a solar-based energy system able to meet 100% of the world energy demand. Such a system is called a Zero-Entropy Energy (ZEE) system [more i44]. And the ZEE technology is still rapidly advancing.

The sole requirement for materialization of genuinely sustainable energy system is a paradigm shift. Only by means of a ZEE system it would be possible to reverse the trend of increasing damage to the environment and to return the human-made entropy morass into solid order.

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About this study

History

This report is a major update of of the report published on this website in August 2005:Nuclearpower,theenergybalance, by Jan Willem Storm van Leeuwen and Philip Smith.

The cooperation of Smith and Storm van Leeuwen started in 1981, when Storm van Leeuwen worked at CE Delft, preparing a report on nuclear power on request of the Dutch Government. This report has been published in 1982 [Q1] and a continuation of it in 1984 [Q5] and 1987 [Q3]. After that year nuclear power got out of focus in the Dutch energy policy for a dozen of years.The study restarted in 2000 as an update of the reports from 1982 and 1987, on request of the Green Parties of the European Parliament, in order to prepare a background document for the UN Climate Conference CoP6 at The Hague, 13-24 November 2000 [Q7]. After that conference the results were placed on the web in 2001. The idea was to start an open global discussion on scientific arguments with regard to some less-known aspects of nuclear power, without fixing our position beforehand. This idea turned out to be a great success. Many critical comments from scientists all over the world have been incorporated in the study during the past years.

Sadly, friend and colleague Philip Smith passed away shortly after the publication of the revised report on the web in 2005. Since then Storm van Leeuwen continued the work, in cooperation with numerous other scientists all over the world. The report of August 2005 is no longer available on this site.

A major update of the report has been finished and placed on the web in February 2008.The youngest update and revision has been finished in July 2012 and is available as pdf file.

Peer review

The author gratefully incorporated numerous comments and critical questions from consultants, NGO’s and scientists at large companies, universities and other scientific institutions. A selection:

Australia University of Sydney, University of New South Wales, Monash UniversityBelgium NPX Research Leuven, IMEC LeuvenGermany Univerität Regensburg, Öko Institut DarmstadtItaly University of FlorenceNetherlands University of Utrecht, Technical University Eindhoven, ECN PettenSingapore National University of SingaporeSpain Bank of Spain EconomicsSwitzerland CERN Geneva, ETH ZürichUK Imperial College London, University of Edenburgh, Oxford Research Group LondonUSA Brookhaven National Laboratory, Columbia University New York, Princeton University

The report of 1982 and its methodology has been peer reviewed by the publication of a short version in EnergyPolicyin 1985 [Q2]. This article is available on this site as pdf file.

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Methodology

Our method is an energy analysis, describing the energy and mass flows of a complex system. This requires a complete life cycle assessment (LCA) of the system: a detailed description of all processes needed to produce electricity from uranium, starting with the mining of uranium ore and ending with the final sequestration of the waste.

Energy and mass are conserved quantities, whereas the value of money is unpredictable beyond a short time horizon. Especially in the case of nuclear energy this is an important feature, because the completion of a nuclear project – from cradle to grave – may take 100-150 years, an unprecedented timeframe.Each nuclear power plant leaves behind an energy debt. The time at which the energy debt should be paid is not fixed, quite differently than monetary debts. The latter are, in economic calculations, discounted at an assumed interest rate, and are further subject to the variations in the value of money. Energy debts cannot just be written off as uncollectable,

An energy analysis of a complex system is not very common in a time in which so many kinds of problems are approached mainly from an economic point of view. In our view an LCA and energy analysis is the best way to assess the long-term aspects of an energy technology, free of unquantifiable variables and (often implicit) time- and place-dependent assumptions.

The methodology of energy analysis as applied in this study has been developed and scientifically validated during the 1970s and 1980s. The methodology is discussed in detail in Part C and Part F4 of the main report, with numerous references. See also the chapter Critiques on this site.

References

Q1 Storm van Leeuwen JW,

EnergieanalysevanenPWRkerncentrale,

Rapport voor de Stuurgroep Brede Maatschappelijke Discussie Energiebeleid te Den Haag, Chaam, 14

september 1982. (in Dutch, for the Dutch Government)


‘Nuclear Uncertainties. Energy Loans for fission power’,

EnergyPolicy, pp. 253-266, June 1985.

Q3 Storm van Leeuwen JW & Daey Ouwens C,

Contra-expertisekernenergie,

Part of: Duurzame energie: een toekomstverkenning,

Krekel VanderWoerd Wouterse, Rotterdam, 21 July 1987. (in Dutch, for the Dutch Government)


Atomstrom,einEnergiedarlehen?, (in German),

Gruppe Ökologie, Hannover/Braunscheiger Arbeitskreis gegen Atomenergie, Hannover/Braunschweig, Mai

1984.

Q7 Storm van Leeuwen JW, Kersten W, De Rijk P & De Roo A,

ComingClean.Howcleanisnuclearenergy?

GroenLinks in the European Union/The Greens/European Free Alliance,

Utrecht/Brussels, October 2000.

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Critiques

Several critiques from the nuclear world on this study have been published. For the nuclear industry the divergent results are reason to dismiss a priori this study at all, ignoring scientific arguments. Often physical and chemical observations are refuted on economic arguments.To scientists and decision makers who are not well introduced in this matter it may be difficult to judge these critiques on their scientific value, due to complexity and opacity of the nuclear energy system. For that reason this section briefly addresses a number of factors that might explain differences between the results of this and other studies:• perspective: scientific or economic• complexity of the nuclear energy system• methodology: defining the system boundaries and time horizon• database: empirical data and proved technology, or technical optimism and paper concepts• data: paucity and secrecy• inherent uncertaintities• attitude: long-term sustainability or a stance ofaprèsnousledéluge• thermodynamic assessment of uranium resources• other arguments.Different approaches may lead to divergent results of analyses by researchers with different backgrounds, views and interests.

Scientific or economic approach

This assessment is based on scientific insights and conserved quantities, such as energy and mass. The units kilogram and joule do not depend on the place and/or time of an observed phe-nomenon. For that reason an energy analysis can have a long-term forecasting value. Especially in the case of nuclear energy this is an important feature, because the completion of a nuclear project may take 100-150 years, an unprecedented timescale.

The value of money is unpredictable beyond a short time horizon. In an economic approach unquantifiable variables and implicite assumptions may play a part. Typical of the economically oriented approach are, for instance, the ways the availabilty of material resources and the energy debt are treated. The price of commodities, e.g. uranium, are pivotal in the economic approach and debts are discounted at an assumed rate. The price of uranium is not an unambiguous quantity, but depends on several unquantifiable and unpredictable variables.

Each nuclear power plant leaves behind an energy debt. The time at which the debt must be paid is irrelevant, quite differently than monetary debts. The latter are, in economic calcula-tions, discounted at an assumed interest rate, and are further subject to the variations in the value of money. Energy debts cannot just be written off as uncollectable. A given physical task will take a given amount of energy, whenever and wherever.Assessments based on the market mechanism and commodity prices have little forcasting value beyond a time horizon of a couple of years.

An economic paradigm may also be a clue to the systematic postponement of the back end processes by the nuclear industry. These processes will require enormous sums of money, measured in tens of billions of euros, without any return on investment. Indeed, the sole

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purpose of the back end processes is to let disappear the radioactive waste and its casings forever. Massive amounts of ordered materials have to disappear from the biosphere.

Some conclusions of the scientific assessment are at odds with some conclusions based on economic considerations, see also below.

Complexity of the nuclear energy system

The nuclear energy system comprises an complex chain of some 14 industrial processes, some of which have extremely long time schedules of a 100 years. In fact the nuclear energy system is the most complex energy system ever designed. The distance in space and/or time between two consecutive processes may be very large, e.g. mining of uranium in Australia and conversi-on and enrichment in Europe. In time: if construction starts in 2012, commissioning may follow in 2022 and the first spent fuel may be removed from the reactor in 2024. The final disposal of the resulting radiaoctive waste may occur not before 2100. The complexity and wide spread in time and place are rendering the nuclear process chain not very accessible and transparent The opacity is exacerbated by the paucity of vital data on processes of the nuclear chain.A full energy analysis of the nuclear chain is complicated, not only because of the multitude of processes, but also because of the multitude of variables involved.

Methodology: system boundaries and time horizon

When comparing LCAs and energy analyses of the nuclear system the first look should be at the system boundaries and time horizon in each study. Which processes of the nuclear chain are included in a given LCA and which are not? What time horizon has the analysis? Does it end at the closedown of the reactor or does it extent to the moment of placing the last radioactive originating from the analyzed reactor in a safe and permanent repository? How exhaustive is a given LCA?

As pointed out above, the nuclear system comprises a large number of industrial processes. Each of these process consumes materials, chemicals, equipment and energy, electricity and fossil fuels. The processes can be divided into upstream processes, also called the front end, and the downstream processes (back end). The upstream processes comprise the activities needed to produce nuclear fuel from uranium ore. These all are well-known and mature opera-tional processes. The downstream processes comprise the activities after the nuclear fuel has been spent and the nuclear power plant has been closed down. A number of the downstream processes exist only on paper.

• In regard of the choice of the system boundaries of the life cycle assessment (LCA) and energy analysis the known studies vary widely: which processes are included in the LCA and which are not.This study takes the full nuclear process chain into account, from cradle to grave. Consequently the time horizon of this study lies at 100-150 years. Other studies omit one or more of the downstream processes from their analysis, however unavoidable in the long run. Usually the omitted processes, would occur in the future beyond a time horizon of, say, 10-20 years.

• A second aspect of the system boundaries is the choice: which energy flows are accounted for and which are not.

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This study takes into account all energy inputs of each process, not only the direct energy inputs, but also the indirect inputs. The latter encompass the embodied energy in chemicals, materials, equipment, construction and dismantling. Other studies are not consequent in this respect.

• A third special methodologic feature of this study is the global perpective of nuclear po-wer in a steady state. In a steady state the number of reactors each year connected to the grid equals the number of reactors dismantled and permanantly disposed off in a geologic repository, including the spent fuel removed from the reactor during its operational lifetime. In the steady state all electric inputs of the nuclear process chain are assumed to be produced by nuclear power plants and are subtracted from the gross nuclear electricity production. This convention renders the energy analysis independent of the fuel mix of the local electricity ge-neration and of time-dependent variables.The CO2 emitted by the nuclear system originates from the burning of fossil fuels, mostly die-sel, and from some CO2 producing chemical reactions, such as the production of cement and steel.

Proven technology versus paper concepts,

empirical data versus wishful thinking

The available information on nuclear power originates almost exclusively from institutes with vested interests in nuclear power and from the nuclear industry. Understandably these sources tend to highlight the favourable aspects. Their public relations are usually charactized by a technical optimism, which is not always backed by emprical facts. Not seldom concepts existing in cyberspace only are presented with the same aplomb as if it were operational processes.

The complexity of the nuclear system, combined with its inherent uncertainties, gives room for different approaches in analyzing the energy balance and CO2 emissions of the nuclear system.An analysis started from a technically optimistic viewpoint invariably will end up in more favou-rable results than an analysis from a pragmatic and empirical starting point.

A number of processes needed to safely wind up any particular nuclear power project are still not operational and are existing only on paper, for example the dismantling of nuclear power stations and the permanent safe storage of radioactive waste in a geologically stable repository. Therefore no empirical data on the still-to-be developed processes are available. The nuclear establishment shows a tendency to delete the still-to-be developed processes, however unavoi-dable, from the analysis of the nuclear system.

Wherever possible this study is based on empirical data on energy and material inputs of the processes of the nuclear chain, as functioning at the current state of technology. All technical data come from the nuclear industry.

A number of processes downstream of the reactor operation are still in the design stage and therefore no operational data of such processes are available. The energy input and CO2 emissions of the yet-to-be developed processes are estimated in this study by comparison with analogous processes. For example, the construction of a deep geologic repository can be compared with convential underground mining.The author is aware of introducing uncertainties by this method. However, in our view the results of an LCA including this kind of estimates will be much more reliable and realistic than when

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the yet-to-be developed processes are deleted at all. As it turns out, the input of energy and materials and the accompanying CO2 emissions of those processes might be far from negligible. Though, this observation may be a major reason why these processes are still being passed on to the future generations. Moreover, the numerical values of data of proven processes exhibit often a considerable spread, e.g. of the construction of a nuclear power plant.

Secrecy and paucity of data

The nuclear world is well organised. Due to its strong connection with military nuclear techno-logy, the civil nuclear technology has many secrets to outsiders. For example it hardly possible to obtain the real construction cost of nuclear power plants in France, because the vendor and the operating utility both are state-owned companies.An independent researcher has access only to the data the nuclear industry wants to be pu-blished. Understandably these publications are favourable to the own performance and policy.

Variables and uncertainties

The results of the energy analysis are presented as function of two main variables of the nu-clear energy system, being the operational lifetime of the reactor and the grade of the uranium ore feeding the nuclear system. In addition the spread in the numerical outcome resulting from the spread of the input data and uncertainties of the nuclear chain is given. Several important processes of the nuclear chain are not operational, so the energy input of these have to be estimated. Even the data of ope-rational processes, as published by the nuclear industry, exhibit often a considerable numerical spread. There is no such thing asonecorrect value of the nuclear CO2 emission or operational lifetime of a nuclear power plant.

Long-term sustainability versus aprèsnousledéluge

This analysis covers the entire nuclear chain, comprising all processes which are causally rela-ted with the generation of nuclear power today, regardless of place and time. In our view nu-clear power should be applied in the safest and least unsustainable way, not only in the regions where nuclear power plants are operating, but also in the regions housing other parts of the nuclear chain, such as uranium mining and waste repositories.

The immense quantities of radioacivity produced by nuclear reactors – one 1 GWe reactor pro-duces 1000 Hiroshima bomb equivalents of radioactivity each year – are stored in more or less unsafe locations. The downstream processes are indispensable to pack the radioactive waste and to store it in permanently safe locations, the so-called geologic repositories. All waste from nearly 60 years of nuclear power is still waiting for treatment in unsafe interim storage facili-ties, that will irrevocably deteriorate with time. The radioactive wastes pose an ever increasing risk to health, safety and societal stability. Accidents that will dwarf the Chernobyl disaster may happen every day in Europe, USA and other countries with nuclear power plants.

The nuclear industry systematically passes on the downstream processes to the future. Omit-ting these processes from LCAs and energy analyses enhances the suspicion that the nuclear industry does not intent to perform these unavoidable processes: an attitude of ‘aprèsnousledéluge’.

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Thermodynamic vs economic assessment of uranium resources

Uranium is almost exclusively used as an energy source. The energy required to extract 1 kg of uranium from a given deposit in the earth’s crust is set by the physical and chemical properties of the uranium-bearing rock, such as the ore grade and minerology. As the amount of energy which can be generated from 1 kg of uranium has a fixed value, the net energy content of a given uranium occurrence in the earth’s crust depends on the ore grade and other parameters. This study assesses the world known uranium resources on thermodynamic criteria and classifies them according to their net energy potential, measured in joule/kg uranium.The nuclear industry tests the world uranium resources by an economic criterion and classifies these resources into price ranges, measured in $/kg uranium.

In regard of the outlook of nuclear power in the world energy supply, the conclusions based on the thermodynamic classification are at odds with the conclusions based on the price clas-sification. In the thermodynamic view the future role of nuclear power in a global context will remain small (less than 2% of the world demand). In the economic view the uranium resources, hence nuclear energy potential, are almost limitless.

Other arguments

Governments may have a hidden agenda. Civil nuclear technology is a step to a military nuclear programme, as one may observe in some countries of the world. Moreover, political decisions may be based on other than scientific arguments. The financial interests in the nuclear industry are very large.Institutes such as WNA (World Nucear Association), UIC (Uranium Information Centre), OECD/NEA (Nuclear Eenergy Agency), NEI (Nuclear Energy Institute) and IAEA (International Atomic Energy Agency) have vested interests in nuclear power and are not necessarily independent scientific institutes.

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