fast breeder reactors: the end of a myth?

Fast breeder reactors: the end of a myth?

Dominique Finon

Only very optimistic views of the progress of FBR technology allow one to envisage its competitiveness on a time horizon of 40-50 years. This might occur in the ira- probable context of a trebling or quadrupling of the price of uranium. Even in that case the benefits of electricity production by FBRs would not compensate for the enormous expense of the necessary R&O and eventual com- mercializstion of this new nuclear system. However these considerations seem minor when compared to the economic obstacles presented by plutonium reprocessing from LWRs. Investment in the plutonium associated with the FBR will possibly be more expensive than the actual construction costs.

Keywords: Nuclear power; Fast breeder reactors; Economics

The author is with the Institut Econo- mique et Juridique de I'Energie at the Universita des Sciences Sociales de Grenoble, BP 47 Centre de Tri, 38040 Grenoble Cedex, France.

This paper was the subject of a communication at the Colloquium 'Energie et Soci~t6', organized in Paris by le Groupe de Belterive, on 15-17 September 1981. The communication has been published in French in the Colloquium proceedings (Pergamon Press France, Paris, 1982, pp 225-254).

lSee V. Ziegler, 'Raflexions sur rappro- visionnement mondial en uranium I'hodzon 2000 et perspectives ult~deures', Notes d'information du CEA, No 10, October 1979; and J. Baumier, J. Charles continued on page 306

When France shortly confronts the problem of whether or not to adopt a commercial programme of fast breeder reactors, the economic justification for the use of such reactors (carefully planned for some years by the Commissariat d'Energie Atomique (CEA) and the Creusot-Loire industrial group) will never have been so weak. Official views are to a large extent screened from critical investigation by the maze of complexi- ties inherent in nuclear technologies; and such expert views rely on very simple arguments in which the interested non-specialist cannot readily spot flaws in reasoning.

The non-specialist, overwhelmed by the subject's complexity, is forced to rely on the competence of experts, and becomes reassured by evidence which is actually presented in a peremptory fashion. For example, there is the claimed 60 fold improvement in the efficiency of uranium use, the 'miraculous' way in which such reactors breed new fuel, and the easing of the constraints in uranium supply.

Resource depletion Do not such characteristics therefore mean that fast breeders must auto- matically be competitive in the future by virtue of the unavoidable depletion of uranium resources? Further, if a healthy scepticism leads to the view that the fast breeder programme will never lead to competitive energy production, this 'absurd' idea is swiftly dismissed by the argument that it is essential to take out long-term insurance against the ever-present risks of cartelization in the international uranium market or of acceler- ation in the exhaustion of the world's uranium-bearing resources. For who would deny the continuing depletion of uranium resources through increased exploitation?

Yet such fears of depletion and eventual exhaustion can largely be dispelled when put into a temporal context. Indeed, uranium is a metal which has actually only been seriously sought in the 1950s and, after a long period when exploration was in the doldrums, in the 1970s. One must therefore account for the fact that there is likely to be a rise in estimated uranium resources (currently about 5 million tonnes at $50/1b) in any suggestion of an inevitable long-term scarcity of uranium if there is no immediate recourse to fast breeders. 1

Further, the history of the exploitation of more traditional industrial metals shows how much the knowledge of resources at a given moment is dependent on the strategy of mining companies, and on their expectations of the future requirements for, and prices of, these metals. It

0301-4215/82/040305-17503.00 © 1982 Butterworth & Co (Publishers) Ltd 305

Fast breeder reactors: the end o f a myth?

continued from page 305 and A. Labrousse, 'Les tendances & long terme des surg~n~rateurs et leur place dans les contextes ~nerg(~tiques mondiaux et fran(~ais', Revue G~n~rale Nucl~aire, No 6, 1979. 2See B. Boyd, 'Uranium resources, production and demand', Nuclear Engineering International, November 1979; M. Grenon, ed, The Nuclear Apple and the Solar Orange, Laffont, Paris, 1978; and J. Cameron, 'A review of long term uranium resources, problems and requirements in relation to demand 1975-2025', Workshop on Energy Resources, IIASA, May 1975. 3M. Spriggs, 'The potential of unconven- tional sources of uranium', Nuclear Engineering Intemational, April 1980. 4K. Deffyres and I. MacGregor, 'World uranium resources', Scientific American, Vo1242, No 1, January 1980, p 59.

follows from this, somewhat paradoxically, that known or estimated resources have always grown in relation to increases in demand.

Geological experts themselves are inclined to think that resources of uranium (at $50/lb) could be five times greater than present estimates.2 A doubling in the price of uranium would make profitable the exploitation of important non-conventional resources and of traditional ores at a grade ten times poorer than c u r r e n t levels ; 3 and a lowering of the grades considered usable would lead to a geometric increase in resources. 4 However, the wise economist will set against this the prospect that the real costs of extracting uranium are likely to increase dramatically (a tripling, or greater) in the next 50 years.

Prestige However, if the uranium resource depletion argument is not yet a particularly strong one, support for fast breeders is often provided on the grounds of the industrial and technological prestige to be derived from such a programme. Indeed, it is a brave man who would argue for giving up the possibilities offered by fast breeder technology when the technical difficulties seem on the point of being overcome and when other industrial states are envious of the success of the French programme.

The Malthusian and nationalist arguments of the proponents of the fast breeder programme unremittingly drive the non-specialists into a comer, until they themselves begin to admit the attractions of fast breeders. In this way criticism becomes dampened, and non-specialists no longer even pause to consider whether a very expensive R&D programme is actually worthwhile (15 billion (10 9) real francs already spent, and at least as much again needed to reach commercial viability). The ground has been so well prepared by propaganda that few voices in France now ask for a complete reappraisal of the fast breeder programme.

There is nothing more difficult than challenging conventional wisdom, particularly when the subject matter is not straightforward. But because the economics of nuclear power are so complex, our critique must draw on a welter of complex arguments before we can reach a straightforward and rather definitive conclusion about a subject area which is still fraught with uncertainties. And that conclusion is that fast breeders will not be capable of producing electricity competitively. The reason is the extreme difficulty of reprocessing, on a commercial scale, the oxide fuel from light-water reactors to produce the plutonium stock required for the entry of fast breeders into commercial service.

To reach the conclusion that fast breeder reactors (FBRs) are not competitive, it is not necessary to consider the substantial technical problems which will hinder the commercial development of FBR fuel reprocessing, even though it is quite legitimate to undertake such an analysis.

But, before going into the narrower question of the future competitiveness of the FBR, it is necessary to locate the subject in the more general issue of the evaluation of the whole development programme and commercialization of this technology. Such an evaluation has never been carried out in France.

T h e need for a to ta l app ra i s a l

A decision on whether to speed up the commercialization of the FBR must take into consideration three irreducible constraints.

306 ENERGY POLICY December 1982

5Ff12 billion for each reactor, Ff5 billion for the fuel fabdcatiofl plant for the fuel elements for reactor cores, and Ff15-20 billion for a reprocessing plant with a 200 tonnes/ year capacity (18 tonnes of Pu/year). 6j. Charles, Le c6ut du nucl~aire. Session d'dconomie de I'dnergie, IEJE, Grenoble, June 1980. 70.15cf/kWh net credit of plutonium on a total cost of 12ct/kWh (in 1979 prices) for a fast breeder at the breeding rate of 25%, see Charles, ibid. 8Baumier, op cit, Ref 1.


The need for a very high level of minimum commitment

Bringing FBRs to the point of commercialization implies the development of a full nuclear system, and not merely the development of a new type of nuclear reactor. It implies the erection of a whole infrastructure of plant for the fuel cycle (fuel fabrication, reprocessing etc), and thus is not analogous to a seemingly similar decision to follow a traditional nuclear programme. Hence the decision to bring FBRs into commercial production takes on the character of 'all or nothing', which is compounded by the indivisible nature of the plant involved in the fuel cycle. The current CEA and Novatome projects (which aim at the installation within the next 10-15 years of four Superphenix II 1500MW reactors and of fuel plants capable of servicing five reactors) imply a minimum financial commitment of 60-70 billion francs.S

The FBR commercialization is, in this respect, to a large degree irre- versible, since once the infrastructural base has been installed, it will be difficult to withstand the pressures pushing the programme forwards.

There is a further factor which impinges greatly on any decision to proceed with fast breeders. This is the need for reprocessing fuel from light-water reactors (LWRs) before being able to build up a plutonium stock for FBRs. By comparison, the decision to follow a light-water programme does not require immediately acquiring reprocessing facili- ties, but this has knowingly been ignored in France. This fact lies at the centre of the problem of the fast breeder programme, as will be seen below.

Competition from a more tried and tested programme

The market for nuclear reactors is dominated by light-water or heavy- water technologies, in relation to which fast breeders do not actually constitute an innovation in the sense that their output is not different from that of light-water reactors. The advantage of FBRs technology will not actually be realized for electric utilities in terms of significant savings in production costs. The CEA estimates 6 that the credit from the annual surplus of the plutonium produced, amounts to 1% of the future cost of the breeder electricity.7

With regard to improved uranium use, this requires the costly employment of a mixed uranium oxide and plutonium oxide (UO2 + PuO2) fuel containing 15% plutonium, which is itself far from cheap. At any rate, even though optimistic estimates such as those of the CEA 8 might show that FBRs could be competitive in the long term, construction of at least 30 reactors will be necessary to provide a reasonable comparison with technology which by then will be much better tested, studied, standardized and regulated. On what basis would an electric utility abandon such a technology for a much less certain new one, and which would not bring improvements in terms of competitiveness?

Interdependence between activities at very unequal stages of commercialization

The interdependencies between the technology of fast neutron fission reactions and activities at much less advanced industrial and technological stages - such as reprocessing fuel from LWR or afortiori from fast reac tors - are going to make it difficult for the FBR to become economically viable.

A private communication from a CEA expert makes it clear that the

E N E R G Y P O L I C Y D e c e m b e r 1 9 8 2 3 0 7


9At present, the French experience in reprocessing FBR fuels is limited to the AT1 unit (lkg U + Pu/day) at la Hague and to the SAP pilot plaht which started up in 1978. The TOR plant, planned to reprocess Phenix fuel, is under construction at Marcoule (start-up in 1984). The PURR plant project was due to start in about 1985. CEA projected commencement of service in 1991 (Echos CEA, No 1, 1981), but delays in the various phases - pre-project, project planning, construction, inactive and active trials for a new plant type- mean that start-up cannot be expected before 1998/9. l°Reprocessing at a cumulative level of 1500 tonnes from now until 1990 (ie 11 tonnes of Pu produced), when the UP3-A plant will enter service and which will reach maximum capacity three years later. Despite the curious decision of the then- Minister for Industry to commence the UP2- 800 and UP3-A projects only days before the new French President took office in May 1981, the UP2-800 project will still have a number of problems to iron out. Thus one can expect a cumulative reprocessed tonnage of 6500-7000 tonnes (1500 tonnes for HAO-UP2, 5150 tonnes for UP3- A) from now till 2000. 11About 55 tonnes of total plutonium or 7400 tonnes of reprocessed irradiated fuels. 12For example costs of studies for reactor improvement, cost of research on safety, cost of pilot projects for fuel fabrication and reprocessing, the additional cost of pre- commercial demonstration reactors. laFor example what quantitative value should be assigned to insuring against the risk, over the very long term, of uranium scarcity? This implies a political as much as economic judgement about the degree of risk and about the social preference over time (see J. Surrey, 'The FBR: the policy background', The Fast Breeder Reactor, Colin Sweet, ed, MacMillan, 1980). Simi- larly, what quantitative value should be given to the industrial policy argument when it seems less and less probable that export markets will have opened up in 3 0 ~ 40 years time? How are we to distinguish between the different kinds of risks (environmental, security, proliferation etc) raised by FBRs and their associated activities and those presented by the more traditional nuclear activities?

P U R R plant (scheduled to reprocess fuel from the Superphenix and the next four fast breeders) will not enter into service before 2000, rather than 1991 as officially planned.9 Thus the cycle for these reactors cannot be fully complete before then, and it will be solely reliant for fuel inputs on plutonium reprocessed from LWRs.

Yet, in the current state of operation of the HAO + UP2 plant, the stage reached by the UP2-800 and UP3 projects, and what is available from the Hague reprocessing plant, 1° the maximum quantities of plutonium which will be produced between now and 2000 will enable, at best, the start-up and operation of just one 1500MW FBR, brought into service in 1990, in addition to the full operation of the Superphenix. 1~ Such a prospect is in contrast to the objectives announced for the year 2000 by the CEA and Novatome (16-23GW announced in 1978, reduced to 10-11GW in 1980).

Further, at the present stage of development of reprocessing FBR fuel (where the irradiation rate is three times higher and plutonium concentration is 10-15 times greater), is it really a serious suggestion to maintain that this process can one day be developed on a commercial scale without costs reaching astronomical levels, bearing in mind the difficulties involved in LWR reprocessing?

Ignoring these interdependencies and uncertainties means that one can mask the, perhaps insurmountable, difficulty which this programme will face in trying to achieve some hypothetical level of economic and commercial viability. This difficulty derives from the extra- ordinarily protracted delays in building up the stock of primary plutonium for the next group of reactors. These delays will prevent benefits being derived from the eventual advantages of a series of orders or economies of scale in reactor construction and the activities of the fuel cycle.

Simple comparisons of the production costs of one kilowatt hour (kWh) from a fast breeder programme with that from an LWR programme over an imprecise timescale, completely overlook the factors deriving from the dynamics of bringing FBRs into commercial production. Marginal calculations of this type are no substitute for a global analysis of the breeder system, including the whole R&D programme.

The latter alone would be able to justify a massive publicly funded research, development and demonstration effort. The only rigorous method of assessment is based on a cost-benefit analysis which would take account of all the constraints affecting the programme's development. Such an analysis would enable comparison of the future benefits to be derived from building up the programme (in terms of for example cost savings, lower levels of dependence, industrial effects) with the expenditure on development and commercialization. 12

Such a cost-benefit analysis must also have provision for calculating the social profitability of various development alternatives for breeders (for example, different levels of commercialization) and for comparison with other research programmes in the energy field. Rigorous and exhaustive assessment is obviously a very difficult exercise bearing in mind the host of different parameters and uncertainties involved, and in view of the fact that a number of factors are not easily quantifiable. ~3

Yet at present, when an industrial-scale breeder programme is just beginning in France, there seems more than ever to be a pressing need for such an evaluation to clarify the decisions that must be taken. But here, in order not to complicate the argument, the approach used is deliberately

3 0 8 E N E R G Y P O L I C Y December 1982

u

~I LWR'°nce-tl~r°ughcyOe/' T 1 ~, I c

Plutonium price

F i g u r e 1. Cost price and plutonium price for FBRs and closed-cycle LWRs.

tAIf we postulated (pure hypothesis) that FBRs, from the year 2000, enabled a cost economy of lcf/kWh and that plutonium availability enabled an increase in the capacity of FBRs by 9%/year until 2030 (the production of FBFI's in 2000 being posited at 50 billion kWh), one could estimate the benefit realized in 1981 values as about Ff3 billion (at 9% discount rate) ie the cumulative R&D expenditure of only three or four years. tsj. Lepine, 'L'6conomie du cycle du com- bustible ~ eau brdinaire', Revue Generale Nucleaire, No 2, 1979. ~6See Appendix 1. rq'he cost of natural or depleted uranium in the cost of FBR-generated electricity is negligible. taA uranium price rise from 450Ff to 1000Ff/kg ($30 to about $70/Ib U308) would'lead to an approximate rfse of 2cf in the price of a kWh. The exchange rate of the dollar is difficult to define, taking into account the disorganization of the international monetary systems; we take a rate of 15 for 5.5. to 6.0Ff.


simplified in that we consider only the chances of FBRs becoming competitive, in the long term, with LWRs. Such competitiveness is a necessary, but not sufficient, condition for the social profitability of the project. 14

FBR competitiveness debatable even with free plutonium

Economic comparison of the two nuclear reactors gives quite different results depending on whether or not one considers the plutonium used by FBRs as the by-product of the light-water fuel cycle. Indeed, in as much as it is such a by-product, its production cost can be considered to be zero. If one must attribute a value to it, we must look for it in the benefits to be derived from its recycling in LWRs or in FBRs. In this argument, it is not F B R development which is going to depend on the value assigned to plutonium (the value being related to FBR competitiveness) but rather the opposite. 15

Price is thus defined in relation to the economies that it enables to be achieved if the lowest threshold of programme development is crossed. In simpler terms, in order that plutonium should have a positive value, with its price set at zero, FBRs must be competitive in relation to closed cycle L W R s (see Figure 1).

Attr ibution of a price to plutonium - by raising the cost of electricity production from FBRs and lowering that from closed cycle L W R s - enables the generating cost of these two sources of electricity to be made equal. Equilibrium level can thus be considered as the production cost of a mixed F B R - L W R nuclear system.

This argument depends on the fact that, because the limited availability of plutonium prevents accelerated replacement of LWR by FBRs which are more economic, the latter reactors must coexist with the LWRs for several decades. The price attributed to plutonium is to some degree a scarcity value (see Appendix 1).

In consequence, when plutonium is considered as a by-product of the L W R cycle, it seems logical, when studying the competitiveness of the FBRs, to make initial calculations on the basis of a zero plutonium price since, even in L W R recycling, its value is zero because of the extra costs of fabrication and reprocessing of the mixed U O 2 -4- PuO2 fuel oxide elements. 16

The chances of FBR competitiveness can thus be assessed by calculating the breakeven plutonium price which would enable FBRs to become competitive with LWRs when the reactors are in commercial production. Indeed, the experts agree that the investment cost per kW of a commercial FBR will always be higher than that of an LWR, and so it is necessary to examine the conditions which allow this disadvantage to be compensated for at the level of fuel cycle cost. Because in our approach, uranium price only influences the price of LWR-generated electricity,17 a uranium price increase would mean an advantage created in favour of breeder reactors.

Further, there are other artificial factors involved in this calculation: the effect of a uranium price increase on the enlargement of the base of economically exploitable uranium resources is not considered. Similarly, account is not taken of the way a uranium price increase would lead to the deteriorat ion of the competitive position of nuclear-generated electricity in relation to non-nuclear sources, la

E N E R G Y P O L I C Y D e c e m b e r 1 9 8 2 3 0 9


19See Baumier, 0/3 cit, Ref 1. 2°lbid and J. Van Dievoet, M. Levenson, and H. Guillet, The RNR Fast Breeder Reactor Fuel Cycle, European Nuclear Conference, Hamburg, May 1979. 2tp. Zaleski, 'Breeder reactors in France', Science, Vo1208, April 1980. 22Taking into account the fact that the con- tracts for construction of Superphenix are now almost all signed, it is possible to place, from trade union information, the construction cost as being in the region of 12-14 billion francs (1981 estimates) without the plutonium. According to official sources, estimates have increased about 25-30% at constant money values. The Superphenix cost is the only current relevant reference in the West, because it is the only prototype of commercial scale under construction. The smaller US, Japanese and German projects are admitted to be extremely costly undertakings. They are costing about the same as the Superphenix but are three or four times smaller-DM5.4 bill ion-(Ff12 billion approximately) for SNR 300 (West Germany); $3.6 billion (with inflation) (Ff18 billion) for the Clinch River Demonstration Plant (USA); more than ¥400 billion (Ffl0 billion) for the 300 MW Monju Reactor (Japan). 2aZaleski, o/3 cit, Ref 21. 2aAbsence of the axial fertile blanket; simplification of the dome; and substitution of stainless steel by ordinary steel. 2SEstimates undertaken by RWE, the German electrical company, use a 50% figure (see A. Eitz, 'The economic interest of the fast breeder reactors', in Fast Breeder Reactors: Economic and Safety Aspects, European Padiamentary Hearing, Strasbourg, 1980). 26See for example A. Ferrari, Kremser and C. Pierre, 'Choix des filieres et utilization optimale des ressources en matiere nucleaire', Annales des Mines, May-June 1978; Baumier et al, 0/3 cit, Ref 1; and Zaleeki, 0/3 cit, Ref 21. 27Baumier et al, op cit, Ref 1. :aThis conclusion would be further re- inforced by the fact that the FBR fuel cycle does not include enrichment activities.

Investment cost of commercial FBRs

Every estimate of the future parameters of the cost of electricity from commercial FBRs is necessarily riddled with uncertainty, beating in mind the level of development of the technology. The economist must therefore identify, from the optimistic information put out by the sponsors of the FBR programme, the elements of industrial maturity of FBRs and the associated activities.

It is clear from official publications that there are unavoidable additional investment costs involved in developing commercial FBRs, by comparison with LWRs. This stems from the presence of an additional circuit (a second sodium circuit) and the greater use of expensive materials (eg stainless steel). 19 Investment costs (evaluated empirically) are estimated to be between 15% 2° and 30% higher than for LWRs. 21 These costs are in part based on the experience gained in construction of the French Superphenix prototype, whose investment costs were about 2-2.3 times higher than those of an LWR of the same capacity. 22

Zaleski 23 estimates that the extra investment costs over LWRs of the next four breeders reduce to about 45% of the above level because of:

• the removal of prototype requirements (which led to a longer construction period; more rigorous studies, engineering tests and trials; one single reactor on site) and those deriving from the management requirements of a multinational project;

• the simultaneous effects of the increase of core capacity of future FBRs from 1200 MWe to 1500 MWe, design simplifications, 24 and the rationalization in production that is made possible by firm con- tracts for several pairs of reactors.

If a fall in cost seems possible as the FBR programme proceeds beyond the minimum level of commercialization, a projected investment cost differential for commercial scale FI3Rs of 15-30% is still, clearly, specu- lative. The experience of LWR diffusion - even though not strictly comparable to the eventual FBR process- suggests a certain caution in estimating costs, since any movement towards a lowering of LWR costs in real terms has not been transformed into actual savings since the start of the commercialization. It thus seems sensible to develop a range of hypotheses about cost differentials: eg 15%, 30% and 50%.2s

Fuel cycle costs for fast reactors

In the absence of industrial experience over the right timescale of 20 or 30 years, every economic assumption about fabrication and reprocessing costs for FBRs, must necessarily be imprecise.

The CEA argues that 3--4 times less [302 + PuO2 is required annually to fuel FBRs by comparison with LWRs, and thus concludes that FBR fuel cycle costs are logically lower than those of the LWR cycle. 26 This difference in the quantities of fuel required would mean that the fabrication and reprocessing costs, per kg of fuel, could be much higher - 4-5 times higher for fabrication and 2.4--4.0 times higher for fuel reprocessing (according to Baumier) 27 - without making the FBR fuel cycle as a whole any dearer than the total LWR cycle.2S

However such juggling around with quantities and costs can lead to error. The limited experience of fabrication and reprocessing of mixed UOa + PuOa fuels - whether for recycling in an LWR (Pu = 4%) or for an FBR core (Pu = 15%or more) - already suggests that it is not possible

3 1 0 E N E R G Y P O L I C Y December 1982

Note: LWR cycle costs do not take account of plutonium credit. Costs of transporting irradiated fuel and waste from FBRs are assumed in reprocessing costs. Differences in figures in column 1

" and column 2 concerning FBR cycle costs are due to the different FBR fuel fabdcatien costs used - Ff 4000/kg in (1) and Ff 100(X)/kg in (2). Ff

10 000/kg was also used in columns 3 and 4.

29Eitz, op cit, Ref 25. 3°Baumier et al, op cit, Ref 1. 3tlbid. 32Our ca lcu lat ions based on one kg of u ran ium at $30/ Ib U30 a,

Fast breeder reactors." the end of a myth?

Table 1. Compadson of LWR and FBR fuel cycle costs, with zero plutonium prk:e.

Official estknate Flevilled eat imat~ C lmel Caee l Case2 Case3

Projection of IWR reprocessing costs (Ff/kgU) 4500 4500 7500 10500 LWR closed cycle costs (d/kWh) 4.0 4.0 5.0 6.0 FBR cycle costs (d/kWh) 2.25-3.0 4.0-4.8 5.2-6.5 6.35-7.5

to contain plutonium fuel costs within the multiples of LWR costs referred to above. In reprocessing the presence of plutonium at very high levels of concentration means that only small quantities can be processed behind the shield of protective walls so as to avoid the risks of high radiation, contamination or criticality accident.

Further, the ability of reprocessing equipment to withstand radiation levels two or three times greater than those so far experienced could still turn out to be a greater problem than currently thought. In the field of mixed fuel fabrication, such difficulties have led overseas experts 29 to suggest FBR fuel-element fabrication costs 10 times greater than those for LWRs (10000 Ff/kg instead of 1000 Ff/kg). With regard to FBR fuel reprocessing costs, it is still almost impossible to estimate what these will be when the reference cost from which extrapolations should be made -ie LWR fuel-reprocessing costs - is still very unclear.

Officially, the cost is given as Ff4500 per kg U, but more likely it is Ff7500-10500 per kg U, as is shown below. Application of an identical multiplying factor to these revised LWR reprocessing costs, to estimate FBR costs, gives much greater gross differences in reprocessing costs per kg of fuel: the Ff6300 difference calculated for official LWR reprocress- ing costs of Ff4500/kg U would rise to Ff10500-14700 for a Ff'/500-10000 kg U cost (when multiplied by the official factor of 2.4).

Even if we accept the CEA estimates for the multiplying factor 30 between the two respective reprocessing costs, the rise in FBR fuel fabrication costs from 4000 to 10000 Francs/kg leads to a rise in FBR fuel cycle costs of 1.8 cf per kWh (the difference between columns l and 2 in Table 1). This makes it impossible for the FBR programme- in the current state of the uranium market - to give a fuel cycle cost, with a plutonium price of zero, that is cheaper than that of the LWR cycle (see Table 1).

Table 2. Off lckd-type ccmpedaon of coats of e ~ - t t k ~ g = n m t ~ by = = m . ~ = ~ FeR v LWR (in ¢enffi lmll per kwh).

FBR LWR

Investment 10 8.5 Operating cost 3 3 Fuel cycle 2.25-3.0 4.5

Total 15.25-16.0 16.0

Note: Estimate is based on economic conditions at January 1981. Plutonium price is taken as zero in this estimate, as opposed to official estimates where it is given as 70-100 francs/gram

Breakeven price of uranium

Thus there would need to be a significant uranium price rise if there is to be compensation for the disadvantage to FBRs of their investment costs - which would not be so in an estimate carried out on the basis of official projections, 31 in which the cost of FBR electricity appears lower than an LWR-generation kWh (see Table 2).

With a plutonium price of zero, the price of uranium would have to double or triple from the current level of Ff400-450/kg U ($30/lbUaOa) 32 for FBRs to become competitive in even the most optimistic projections (ie low investment costs and/or low fuel cycle costs at the current price of uranium) (see Table 3).

A doubling of the current price of uranium would lead to an increase in the cost of LWR electricity of about 1.6cf/kWh. In this case the most optimistic difference in investment costs for FBRs (750 francs/kW) would be just about compensated for by such a uranium price rise, if the

ENERGY POLICY December 1982 311


Note: Method of calculation of price equivalence is explained in Appendix 2.

33A recent US study gives comparable breakeven prices: B. Chow, 'Comparative economics of the breeder and light water reactor', Energy Policy, Vol 8, No 4, December 1980, pp 293-307. We have not entered in to the discussions on the projections of LWR and FBR operating per- formance. Lowering the load factor from 72% to 60% would increase the difference in investment cost per kWh by 0.25cf/kWh for investment cost differential of Ff750/kW and by 0.50cf/kWh for Ff1500/kW. 34Sometimes arguments deYived from this basic principle are used by apologists for the FBR programme, who maintain that FBRs are the best means of getting rid of the plutonium produced by the LWRs. It is not only raprocessing that seems to have an element of inevitability: FBRs must be developed, whatever the cost, to get rid of the plutonium, electricity being only a by- product of this activity. 3SThe recovered uranium is lightly enriched (0.9%). But it contains neutrophagous isotopes (U36 becoming Np237) or radio- active isotopes, which are likely to create radioactivity protection problems in re- enrichment and fabrication (Np237, U232).

Table 3. Value of break even uranium price (Ff/kgU).

Difference of Inveslment (rest, Oiffemnce of fcel ceM, FBR/I:'WFI (FflkW) FBR/PWR (In of/kWh)

0 1.0 Case A (15%) 750 875 1160- Case B (30%) 1500 1250 1535 Case C (50%) 2250 1625 1910

optimistic case for FBR fuel cycle costs (the same cost as for the LWR cycle at the current price of uranium) applies. In any event, even in this favourable scenario, the final FBR cost advantage will only be about 10% (1-2cf/kWh) if the uranium price increases to three times the current level of $30/lbUaOs.

These optimistic hypotheses on FBR costs are not really likely to apply for at least 40 years in view of the industrial constraints on the FBR programme (for example the slowness of the learning factor, regulating adjustments, slow technical 'maturation' of LWR and FBR fuel reprocessing, plutonium availability etc). In view of this and of the likely effects of carrying through an FBR programme over the next 40 years and beyond, the total savings ultimately made by the electric utilities will never be able to make up for the amount spent on the programme's development and commercialization.

For that to occur, uranium prices would need to rise much higher - and one can only speculate about this. Although on the one hand, uranium demand does seem to be permanently affected by the crisis in nuclear programmes, on the other a uranium price rise will logically give rise to a much greater proportional increase in economically exploitable resources, as noted above, which will have a constraining effect on the economic pressures to develop FBRs.

Even if we consider plutonium as a 'free' good, with zero price, FBRs are a long way from being economically competitive, and afortiori their social profitability does not remotely correspond to the claims of sup- porters of the programme.

It is i m p o s s i b l e for F B R s to be compet i t i ve

All the above constraints rest on the basic assumption that the reprocessing of LWR fuels is an inevitable operation made necessary by the requirements of good management of nuclear waste. 34 With such an assumption,it is no longer necessary for the expenditure on reprocessing to be recovered from the returns derived from the use of low-enriched uranium 3s and plutonium in FBRs or in LWR recycling. Thus for some years the financial balance-sheet of LWR fuel reprocessing in official estimates has actually been negative (see Table 4), even though these estimates ascribe to plutonium a price based on its notional value in a hypothetical LWR recycling process (70-120 francs/gram).

Such a balance is thus considered as the cost of the good management

Sources: Reports of the PEON Commission. Note: The coat of the back end of the closed cycle includes costs of transport of irradiated fuel, of reprocessing and of temporary and final storage of nuclear waste.

Table 4. Evolution of the net cost of the beck end of the ctom~ cyc~ (of/kWh).

1973 1976 1979

Gross cost 0.07 0.32 0.85 Uranium credit -0.08 -0.29 -0.26 Plutonium credit -0.09 -0.18 -0.17

Net cost -0.10 0.15 0.42

312 ENERGY POLICY December 1982


of nuclear wastes. But such an economic view of the back end cost of the fuel cycle is only acceptable if reprocessing is considered the sole possible method. But studies carried out for several years in Sweden, Germany and the USA on the once-through cycle (a long period of temporary storage, then permanent storage of irradiated fuel) show that reprocessing should no longer be considered an indispensable activity. Hence there will no longer be any economic justification for electric utilities to buy reprocessing services to recover, at a loss, the fissile materials, if this loss is greater than the costs of the non-reprocessing option. The uranium and plutonium recovered would need at least to make the back end cost of the closed cycle equal to the back end cost of the once-through cycle.

36For underwater stockpiling, see The KBS II report: Handling and Final Storage of Unreprocessed Spent Nuclear Fuel, KBS, Stockholm, 1978; AEN-OCDE, 'Stockage des elements-combustiblas irradies', Seminaire AEN-OCDE, Madrid, June 1978. For dry stockpiling, see Nuclear Fuel, 14 May 1979; Nucleonics Week, 20 December 1979; and R. Davidson (TVA) and D. Dlacon (GE), Spent Fuel Storage, Confer- ence ANS, Washington, November 1980. 37For these see J.P. Schapira, La GesUon des Dechets RadioacUfs, Session I'Economie de I'Energie, IEJE, Grenoble, June 1980. 3STwo projects, one by General Electric for the "I'VA and the other by Boeing, are also under way in the USA (see Nuclear Fuel, 29 September 1980 and 27 April 1981 ). 39See for example the statements on this subject by a former Minister of Industry in the magazine Le Point, 19 September 1977. 4oBattelle Memorial Institute, Pacific Northwest Laboratory, Report Battelle- ERDA-76-43, 1976. 41The plutonium from irradiated fuel is not totally r e ~ a b l e because of losses in reprocessing and rafabdcation in highly irradiated atmospheres. Losses are of the order of 4--5% (CFDT, 'Syndic, at national du personnel de 1'6nergie atornique', in Le Dossier ~lectronucl~ire, Seuil, ed, Paris, 1980). 42Amedcan Physical Society, Report to the APS by the study group on nuclear fuel cycles and waste management, Review of Modem Physics, No 50, 1978.

N o n - i n e v i t a b i l i t y o f r e p r o c e s s i n g o f ox ide fuels

For a long time reprocessing has seemed to be an economic activity that is easy to develop and exploit in favourable economic circumstances. Con- sequently, the alternative option has been much less studied and great hopes have been placed in FBR programmes. It was taken as self-evident that temporary storage, and the permanent storage of irradiated fuel was inconceivable because it was riskier and more costly than reprocessing the waste.

It was not until 1975/76 that the once-through cycle began to be seriously considered in the countries mentioned, because of the political or legal freezing of reprocessing. Research carried out since then has shown that temporary storage for long periods in ponds or dry storage in special containers can now be considered operational. 36 Without entering into too many technical details, 37 we must emphasize that the LWR fuel elements are particularly well adapted to prolonged storage over several decades, since they are designed to withstand very severe conditions in use (vibration, high pressure and very high temperatures).

At present long-term storage ponds are being constructed in Sweden as part of the CLAB project; total capacity will reach 3000 tonnes in 1985. In the USA various projects of this type from 3000 to 5000 tonnes are under study (eg by the Tennessee Valley Authority or Dupont de Nemours). Dry storage in containers used for transport requires negligible sur- veillance. This has been studied in detail by the German firm DWK which in 1980 began the authorization procedure for installation of two dry storage centres of 1500 tons each.3a Permanent storage of irradiated fuel in geological formations is foreseen in about 30-50 years. The safety principle for this typeof storage rests on the remarkable capacity of uranium oxide to retainplutouium and other by-products.

The relative advantages and disadvantages of the two options now seem clearer. It seems, at least, ill-considered that in justification of the reprocessing option a much lower quantity of waste requiring storage is taken into account than the amount of irradiated fuel requiring management in the alternative option (3m 3 per year for a 1000MW reactor in the first option, as opposed to 14m 3) .39 In practice it is not only a question of high-activity vitrified waste; the Battelle Institute 4o has shown that reprocessing produces more than 125m 3 of low- and medium-activity plutonium-bearing wastes, 41 the storage of which requires important precautions because of the reconcentration of alpha-emitting activity brought about by their stockpiling in large quantities. 42 For a cost comparison of reprocessing and non-reprocessing options see Table 5.

In terms of expenditure, the once-through cycle option is 5.5 to 10



Notes: The discount rate is 9% and is applied from the date that material leaves the reactor. Costs of storage of low and medium - activity wastes is not included in reprocessing ol:Xion costs, in official French ~cul~ior~. Sources: For pond storage over 10 years, see US projects described-in Nuclear Fuel, 28 April 1980. For dry storage over a long period see GE and Boeing work described in Nuclear Fuel, 28 September 1960 and 27 April 1981, and German project described in Nuclear News, November 1979. For permanent storage, see Swedish study KBS II, Handling and Final Storage of Unreprocessed Spent Nuclear Fuel, Stockholm, 1978.

Table 5. C o m P m t ~ of the dlecounted coMs of the ~ option (ofllclal figure) and the non-reprocee~ng option (economic cmtdlUo~ at Januery 1N1).

Datays In the dilcountlng DIKounted value calculations Groin value Ff/kg Ff/kg

Reprocessing option Transport 0 250 Reprocessing and treatment 3 4000 Interim storage 3 400 Uranium credit 3 500 Plutonium credit 3 600 Permanent storage 40 600

Total

Non-reprocessing option Pond storage 0 100-250 Transport 10 250 Long-term dry storage 10 400-750 Permanent storage 40 600-850

Tot~

250 3224 322

-366 -44o

21

3010

100-250 120

180-340 2o-3o

420-740

43For the sake of clarity, we do not consider a third possible system comprised of two types of LWRs in a closed system - 'plutonium producing LWRs' and LWRs which consume recyded plutonium. I. Bupp and J.C. Derian, 'The breeder reactor in the US: a new economic analysis', Technology Review, July-August 1974.

times cheaper than the closed cycle option. This calculation still uses official estimates for reprocessing costs and incorporates credits deriving from the hypothetical recycling of the plutonium in LWRs. Any discounted cost comparison which allows for the staggering of expenditure over time gives very similar results with a uranium price 2 or 3 times the current level. Tripling the price, for example, would only alter the cost difference (which is about 2500Ff/kg U) by about 700 Ff/kg U.

Consequently, if considerations of safety and environmental protection allow us to consider reprocessing as no longer the only option, the decision whether or not to choose reprocessing becomes entirely one of economic rationality. The electric utilities must rigorously decide whether the projected returns from reusing uranium or plutonium (the price of which is estimated at its value in use) are sufficiently higher in the closed-cycle that they compensate for the lower costs of the once-through cycle option. This will depend on the utilities' expectations about uranium prices.

At the theoretical level, it is no longer possible to envisage just one nuclear system, viz the mixed FBR-LWR system in a closed cycle; but rather, two competing nuclear systems, the mixed system and a system composed solely of LWR reactors in a once-through system. 43 The nuclear system that is chosen by the electric utilities will be the one which produces the cheapest electricity.

Let us take the optimistic scenarios (1 and 2 in Figure 2) in which FBRs are competitive with LWRs in closed cycle at a plutonium price of zero.

Figure 2. A comparison of optimistic scenarios with a zero plutonium price. Note: LWR1 = dosed cycle; LWR2 = once-through cycle.

norio I

A Col ,WR z . . . " ~ . . ~

il Plutonium price (Ff/g)

CE

Scenario 2

LWR I

,, • I

p~ p~ Plutonium price (Ff/g)

314 E N E R G Y POLICY December 1982

I Scenorio 3

-~ ~7~:::=~----_.~ ~LWR, Closed cycle

1 ,' T N i t L

PE Plutonium price (Ff/g) PR

F igure 3. A comparison of costs v price for a third scenario.


For electricity from the mixed system to be competitive with that from once-through LWRs (scenario 1), it is necessary for the value of the plutonium to be higher than the price at which reprocessing is profitable. ~ In simple terms, the competitiveness of the mixed system is guaranteed when the value of plutonium in FBR use is higher than the surplus costs of reprocessing over storage.

In the more probable scenario (3) (see Figure 3) in which FBRs will find it difficult to be competitive in 40 or 50 years from now with closed- cycle LWRs at a plutonium price of zero, it is totally uneconomic to consider developing a mixed system. The electric utilities would indefinitely have to meet the additional LWR reprocessing costs which will undoubtedly increase further until the process reaches commercial 'maturity'.

44The plutonium price which makes reprocessing profitable is that which erH~bles the closed-cycle back end cost to be less than the open-cycle backend cost, at the expected uranium price. 4Sin the USA, the West Valley plant (300 tonnes/yeer) was shut down for alterations in 19~2 and was finally abandoned in 1976; the Morris plant (3(X) tonnes/year), com- pleted in 1974, was nevdr started up because of its non-compatibility with the requirements process. In the UK, the head- end cycle for oxide fuel at Windscale was closed in 1973 following a very serious incident resulting from design error. In Belgium, the EEC plant Eurochemic was closed in 1974 after eight years of operation because it was too expensive. In Germany, the VAK pilot plant was shut down after 10 years after the corrosion of a dissolver. In France multiple technical incidents have occurred with the HAO-UP2 plant which have only enabled reprocessing at a tenth of nominal capacity during runs with oxide fuel. 46The 135-day run of HAO-UP2 in 1981 enabled reprocessing of only 55 tonnes. West Valley reprocessed 250 tonnes of LWR fuel in six years. VAK (RFA) reprocessed 110 tonnes in tan years when it had a nominal capacity of 40 tonne¢~/ear. 4"r]'hJs is only hypothetical, gDan that it is impossible to draw conclusions in this way when the plant has not been observed over its technological Iffe~oan of 10--15 years.

aln harms per reprocessed kg, economic conditions at January 1980.

The real cost of reprocessing LWR oxide fuel

Twenty years of slow progress have been required before we have been able to start defining the characteristics of a reliable reprocessing plant. During this period, world experience has been characterized by resound- ing failures and many 'incidents '4s which have demonstrated the intrinsic problem in marrying the objectives of economic profitability with growing requirements for the safety of workers and environmental protection.

At the same time, the uniqueness of this industrial activity has been clearly brought home by the unusually long periods of shut-down caused by minor incidents. For example, the Tokai Mura plant (210tonnes/year) in Japan which started up in August 1977, was shut down for 18 months in 1978/79, following the corrosion of an evaporator. In plants which func- tioned, or are still functioning, the annual quantities reprocessed have rarely reached a third of nominal capacity. The HAO + UP2 plant at La Hague, during PWR fuel reprocessing, has reached 0.4 tonnes/day at best, although the theoretical capacity is 4 tonnes/day. 46 Further, the life of equipment such as cutting and dissolving machinery is very short because of the irradiation that it undergoes.

In such a difficult technological context - which can be traced in the development of official costs - only the government can take on the high financial risks associated with the new projects which build on the lessons learnt in this expensive technological learning-curve (see Table 6). The next generation of French and UK plants (UP2-800 and UP3 at la Hague, and T H O R P at Windscale) are funded in this way: they represent the state of the art in world reprocessing technology. The Soci6t6 G6n6rale Nucl6aire, a subsidiary of the CEA, presented a preliminary outline for the UP3 plant in 1979. This envisaged installing several sets of com- ponents in parallel parts of the plant which met stringent standards for effluent outflows and personnel protection.

This project could be considered as a reference-standard plant, signify- ing that the technology has reached maturity, a7 The cost of the project - 20 billion francs - was considered to be too high by French officials. An 11 billion franc ceiling was imposed and the designers were asked to

Table 6. Evolution of ofildal beck-~KI colt of cloeed cycle, a

1970 1972 1974 1976 1978 1fl80 1N1 435 410 775 1400 3100 3500 4000

E N E R G Y I : ~ I . J C Y D e c e m b e r 1 9 8 2 3 1 5


Table 7. Reprocmming costs of LWR fuel by dse in cost estinmte of UP3 plant (in francs per kgU).

Plant coet Ntimete ~ n g coots (10' francs) (Ff/kgU)

(Case 1) 11 4000-6800 (Case 2) 15 5100-8800 (Case 3) 20 6200-100(30

Note: Estimates include expenditure associated with waste vitrification units. Calculation is based on maximum actual capacity of 650 tonnes/year for 11 and 15 billion Ff estimates and oh 800 tonnes/year for 20 billion Ff estimate. The Idvel of closed cycle back-end costs in each case is obtained by adding irradiated fuel transport and waste storage costs (about 500 Ff/kg) to the figures shown.

48£1.8 billion for T H O R P (675 tonnes/year actual capacity), see The Times, ~' May 1980; DM20 billion for Gorleben (1400 tonnes/year), see French Ambassador to Bonn,' ANB/NI/79-475; and DM4 billion for a new Gehn~in project of 350 tonnes/year plant, see Nuclear Engineering'lnter - national, August 1980. 49Length of pre-construction studies and plant construction: 6 -10 years. Maximum attainable capacity: 650 or 800 tonnes/ year. Length of power build-up: 3-5 yeaPs. Technical lifespan: 10-15 years. Annual operating costs: 450 -700 million francs. Discount rate: 9%. SOWe assume production of 580 billion kWh in 2000 by a reactor capacity of 120 GW, of which 10 GW is FBR. About 2000 tonnes of irradiated fuels would leave the reactors in that year. To simplify the calculation of expenditure, the cost differential of FBR- generated electricity in relation to once- through LWR cycle electricity has not been considered, SlThis characterization is a simplification because it more or less implies that storage of all wastes from reprocessing leads to discounted expenditure identical to that im- plied by storage of irradiated fuel. Repro- cessing is thus the only activity which is taken into account - and this is not really the case.

Note: Calculation includes a plutonium credit based on a price of 80Ff/g to ensure consistency with the methods and dssumptions used by EDF or CEA. Uranium credit is worked out on the basis of a uranium price of Pf500/kgU. These two credits affect the calculation ~ of net discounted costs. Calculation is also made on a presupposi- tion that the electric utility buys back-and services from other concerns (reproseesing and storage of waste on the one hand, storage of irradiated fuel on the other), and compares expenditure from the time of fuel leaving the reactor.

develop a new, less complex project. This was announced in mid-1981, and will inevitably operate in less favourable conditions.

This estimate of 20 billion francs corresponds to estimates for German and UK projects, as Moreover, the 11 billion franc estimate has taken as its basis the official calculation of closed-cycle back-end cost at 4500 francs/kg. We have recalculated this cost for three different project estimates: 11 billion, 15 billion and 20 billion, using different hypotheses for the most important parameters (see Table 7). 49 By adding the fuel transport and interim waste storage costs (about 500 francs/kg) to the cost of actual reprocessing, the estimates obtained lead us to believe that closed-cycle back-end cost is between 7500 and 10500 francs/kgU - much higher than the official figure.

The electric utility which envisages undertaking the reprocessing of irradiated fuel with the sole aim of developing an FBR system must therefore assess the costs of this option in comparison with a strategy which depends solely on a once-through LWR cycle. For example, if we examine forecasts of EDF's nuclear-generated electricity in 2000, s0 the increase in annual expenditure brought about by the former opt ion- already reckoned to reach about 5 billion francs on the official costings of 4500 francs/kgU - would be of the order of 7.5-13 billion francs on more realistic costings. This is roughly the equivalent of investment costs of two or three 1000 MW reactors each year (see Table 8 for a comparison of expenditure).

Thus, logically, electric utilities should bring together the extra expenditure required by choice of the reprocessing option and the investment of plutonium required for the operation of an FBR in a closed cycle.

The stock of irradiated LWR fuel may thus be considered quite simply as a plutonium mine, the reprocessing of which enables extraction.S1 The dilemma for the utilities is thus to know whether electricity production techniques which use this plutonium enable economies to be made by comparison with LWR-generation methods.

In other words, by virtue solely of the viability of the non-reprocessing option, the LWR reprocessing activity should no longer be considered as an integral part of the LWR nuclear system, but rather of the FBR system. Further, only one LWR-generated electricity cost now needs to be taken into account in cost comparisons - the cost from a once-through LWR cycle - since LWR fuel reprocessing costs will be implicitly taken into account in the plutonium production cost in FBR cycles.

Importance of investment in plutonium In these conditions, obtaining the inventory of primary plutonium needed to complete the fuel cycle of an FBR requires a considerable level of investment. Indeed, by defining the cost of the extraction of plutonium as the difference between the cost of the reprocessing option and the

Table 8. Comparison of expanditure mmociatod with fuet removed In 2000 horn once-through and closed cycles for diffwent ~ n g costs.

c __k~__ ~ Or~e-B.~ugh cyc~ Case1 Case2 Case3

Net discounted cost (Ff/kg) . . . . 3010 4430 6850 420-740 Nbt annua expenoitu,¢, (Ffl 09) 6.0 8.9 13.8 0.8-1.5

316 E N E R G Y POLICY December 1982

Note: Credits from uranium recovered and re- cycled in LWRs are taken into account. The estimates made on the assumption of production of 8.5(3 total Pu per kg of irradiated fuel, allowing for

-'losses in LWR reprocessing and in fabrication of mixed UO= + PuO= fuel.

S2The plutonium extraction cost is calculated in the same way as the concept of the pdce which allows reprocessing to be profitable. saThis price is established by reference to a hypothetical value in LWR recycling. S4The substantial emission of heat from irradiated fuel is the basic technical problem in limiting the delay before reprocessing c a n begin. It would in any case be necessary to wait at least ten months to al low fuel to coot on the reactor site before transporting it. Subsequently, the dissolved wastes release considerable quantities of heat if reprocessing is attempted in the short term. The problems are then to remove this heat and to provide adequate shielding. In the case of IWVR fuel, COGEMA reprocasses only after three years of cooling, despite the original expec- tation that reprocessing would take place after six months. SSNote on calculation: Investment cost is worked out by considering the deliveries of Pu as being phased. The delivery of the first load for the reactor (6.4 tonnes) is assumed to be phased over the three years before the reactor enters commercial service. The Pu for reloading is delivered one year before reloading the reactor, which occurs every 15 months.


Table 9. Plutonium exlbraction costs for dlft~Nmt LWR mflrocessing costs.

Caesl Case2 Caes3

Costs of LWR reprocessing and storage of waste (Ff/kgU) 4500 7500 10500 Plutonium extraction costs (Ff/g) 420--460 775-815 1125-1165

non-reprocessing option per unit of plutonium produced, s2 this extraction cost is much higher than the plutonium price of 70-100 francs/g of the official estimates, s3 It is already about five times higher if the reprocessing option cost is taken to be 4500 francs/kg, but 10 times greater for more realistic cost estimates, given the current price of uranium (see Table 9).

The price of uranium influences plutonium extraction cost because uranium credits are subtracted from the cost of the reprocessing option. In consequence, if uranium prices increase, plutonium extraction costs go down. A tripling of the current price of uranium (from about 450 francs to 1350 francs/kgU) would lower the plutonium cost by 100 francs/gram. This result does not affect the orders of magnitude specified above relating to plutonium extraction costs.

To the effects of plutonium production costs on the expenditure required to obtain the fuel needed to start up an FBR (and to complete its fuel cycle) must be added the effects of a more pessimistic evaluation of the plutonium inventory taking into account the out-of-reactor immobilization time of fuel. It has been a long time since the Americans were proceeding on the basis of a six-month period of immobilization.

French estimates are based on an out-of-reactor time of 24 months for Superphenix fuel, which will come down to 12 months for the commercial FBRs. However, it seems that it would be wiser to work on a 36-month period for de-activation of the fuel before it proceeds to reprocessing under satisfactory industrial conditions - which means an out-of-reactor time of about four years (for estimated Pu stock required see Table 10).sa

The amount of plutonium immobilized by a 1500MW commercial FBR would thus be double the officially recognized level, because, in the one case, only one 'reload' (3.2 tonnes) is immobilized whereas four reloads are immobilized in the other. At the current price of uranium, investment in the plutonium required would cost, under these conditions and even at the official LWR reprocessing cost of 4500 francs/kg, about seven to eight times more than is currently estimated - 6.7 billion francs as opposed to 0.80-1.0 billion (see Table11). ss

What can one say about a level of plutonium investment of 12.4-18.2 billion francs for a 1500 MWe FBR which itself costs around 10 billion francs (!981 prices)? A change of 100 francs/gram in plutonium extraction cost together with an exceedingly hypothetical trebling of the uranium price would hardly affect the findings, since it would reduce investment in plutonium only by about 1.5 billion francs in each case.

The decision to develop FBRs is thus clearly constrained by the un- favourable economic characteristics of reprocessing, and by the require- ment to build up a sizeable plutonium stock to complete the reactor's fuel

Note: Assumptions: quantity of Pu in reactor = 6.4 tonnes; renewal by half every 15 months; and 'reload' fuel immobilized outside the reactor is 'de-activated' and thus cannot be used for another reactor.

Table 10. Prknary plutonium inventory required for a I S00MW FaR according to out-of-reactor immobilization times (In tonmm).

Immobilization time (months) 12 24 36 48 Total Pu inventory (tonnes) 9.6 12.8 16.0 19.0



Note: The recovery from invantory is calculated by discounting its value at the end of the lifetime of the reactor. The revised figures are estimated with the hypothesis of an out-of-reactor immobilization time of four years.

S6The plant would reprocees 7200-9200 tonnes of F~NR fuel during its technical lifespan (10-15 years), and produce between 65 and 83 tonnes of plutonium. The primary plutonium stock required for a 1500 MW reactor would be 19.0 tonnes, if the out--of- reactor immobilization time were greater than three years. STA uranium pdce dse of 900Ff/kg (roughly a trebling, from 30 to 90 $/Ib) leads to an LWR generating cost risd of 3cf/kWh and an FBR kWh cost decrease of a ~ u t 1.8cf/ kWh, because of a plutonium pd~:e decrease of 100Ff/g. seSee Appendix 3.

Table 11. Calculation of I ~ in plutonium rlKluimd f~r 1500MW reactor (Idlllon h'ancs).

~ m ~ u n m nm~ed ~mur~ Case1 Case1 Case2 Case3

Plutonium cost (Ff/g) 100 430 790 1150 Number of 'reload' outside reactor 1 4 4 4 Cost of primary plutonium inventory (1 (PFf) 0.96 8.2 15.1 22.1 Recovery from stock in 20 years (109Ff) 0.17 1.5 2.7 3.9 Net investment in plutonium ( 1091=0 0.79 6.7 12.4 t 8.2

cycle. Calculations show that an LWR reprocessing plant of 800 tonnes/ year capacity costing 20 billion francs in direct investment (ie 30 billion with interest charges) and requiting annual operating costs of 0.5-1.0 billion, would, at best, enable only three or four 1500MW closed cycle FBRs to enter service during its life time. Even this depends on the plant functioning under satisfactory conditions, s6

FBRs: definitely non-economic technology For FBRs to have some chance of reducing their economic disadvantage by comparison with once-through LWRs, the plutonium extraction cost should roughly approximate its hypothetical price (value in use) of 100Ff/g. In such a case as shown above, it would be conceivable, within a broader framework of favourable conditions (including a trebling of the uranium price), that FBRs could reduce their investment costs to the level of LWRs.

However, the plutonium extraction costs are much higher than the price based on a hypothetical value in use, (even when taking reprocessing costs to be 4500 Ff/kg). This means that the difference in total generating costs of the respective systems calculated on the basis of the current uranium price - the gaps between A and B lines in Figure 4 - is such that there is little change of reducing this difference through rises in the uranium price (see Table 12).

It is true that rises in the price of uranium act doubly on the differences in cost, by leading both to an increase in the cost of LWR fuel, and to a decrease in the plutonium price and thus in the cost of the FBR fuel cycle, s7 But the level of the breakeven price of uranium at which FBRs would become competitive is such that it is highly unlikely to be reached in the next 100 years - as Table 13 demonstrates, sa

~ C E F ~ L W R , c l o s e d cycle

6

Plutonium price [ Ff/g)

Figure 4. Total generating costs based on current uranium price.

Conclusion The various considerations discussed above enable us to see why international nuclear authorities always defend the inevitability aspect of reprocessing on the pretext that it represents the optimum method of managing nuclear waste. Indeed, it is crucial that plutonium should have the status of a by-product of this activity, in order that extraction costs should at no stage be attributed to it. In this way FBRs can seem economically competitive in the eyes of electric utilities.

If reprocessing is no longer obligatory, it is still possible to develop an argument to justify the higher cost of FBR electricity in relation to the LWR costs at a plutonium price of zero. The excess FBR cost would represent a long-term insurance premium to protect the economy against

318 ENERGY POUCY December 1982

Note: The genera~ng cost of PWRs is calculated with no expenditure on reprocessing- a once- through cycle. We take into account a plutonium surplus of 0.25 tonnes/year. This gives a plutonium credit which is, respectively, 0.76, 1.41,2.2 cf/kW. Calculation assumes four reloads immobilized outside reactor.

SgAIleviating the burden on the balance of payments is often quoted. But in 2010 the uranium bill - for a nuclear capacity without FBRs, and on the assumption that all uranium is imported-wil l be 5-10 billion francs, or 10-20 times less than currently for oil at its present price level. 6OFollowing a CEA study (results published in CEA Notes d'informations, July-August 1978), it was shown that for a very intensive FBR programme (23 GW out of 106 nuclear-generated GW in 2000, 54 GW out of 132 nuclear-generated GW in 2010) where all reprocessing difficulties with LWR and FBR fuel were ignored, it was not until 2010 that annual uranium requirements had halved. So what are the implications for slightly more realistic programmes?


Table 12. ~ of coet of PWR and FBR electdclty at cummt pdce of urenlum (In ¢//kWh) (plutonium price based on its extraction cost).

(~-,c~-throu~) Commercial FBR Case 1 Case2 Case3

Investment costs 8.5 11 11 11 Operating costs 3 3 3 3 Fuel costs 3.25 10.6 17.2 23.6 - of which investment in plutonium - (6.6) ( 12.2) (17.6)

Total 14.75 24.6 31.2 37.7

the risks of uranium depletion. The almost mythical appeal of breeder generation, enabling the progressive replacement of all LWR by FBRs, is thus presented in economic terms: such a replacement will progressively reduce the requirements for, and thus imports of, uranium, s9

It matters little if the characteristics of FBRs only actually allow a very slow decrease in uranium requirements. 6° (Very simple technological adaptations, eg lowering of the tails assay in the enrichment process or increasing LWR 'bum-up' would enable this to be achieved much more quickly.) The important thing is to take a perspective 100 years hence, to ensure supplies of fissile fuels well into the next century. Who would not be swayed by this argument, when confronted by the uncertainties of the international energy market and when national chauvinism is encouraged by past technological successes? Economic rationality has become weakened in an evangelical fervour in which doubts and criticism no longer have any role.

And yet to exploit the miraculous process of 'reproducing fuel from its own ashes' is so costly that it would be economic folly to adopt this as an industrial process for at least the next 100 years. Indeed, the viability of the once-through cycle obliges the economist to attribute the entire cost differential between the two options to plutonium. This would effectively remove any chance of FBRs becoming competitive.

But is the myth of breeder power generation so strong in France that such arguments can be disposed of?. At the present stage when we are on the point of deciding to commercialize FBRs, it seems incomprehensible that arguments based on prestige should again be brought to bear on the decision.

The economic problem with FBRs is not even one of economic uncertainty. It is a simple, insurmountable problem - that of reprocessing. And the least that we can hope for from the new French government is that they should undertake a technological evaluation of the reprocessing of oxide fuels and breeder reactors. So as to obtain the necessary in-depth study required at this time, the expertise of established institutions should not be the predominant voice in such an inquiry.

Table 13. Revised brlmkeven ~ of uranium for altmmative LWR rq=roceeaing coots.

LWR reprocessing 4500 7500 10 500 costs (Ff/kg) (Case 1) (Case 2) (Case 3)

Uranium breakeven (Ff/kg) 2250 3440 4620 (.,~/kg) (173) (265) (335)

E N E R G Y P O U C Y D e c e m b e r 1 9 8 2 3 1 9


Appendix 1 Note on plutonium price The essential value of plutonium is actually much more difficult to calculate than the calculation used until now by nuclear economists. This uses as its basis the cost-savings brought about by plutonium recycling in LWR reactors: Ffl20/gram of fissile plutonium due to a saving of 0.116kg of natural uranium and 0.108kg SWU, from which are subtracted the additional costs of fabrication and reprocessing of fuel elements containing 4% plutonium.

The price used by the Nuclear Agencies is thus about Ff70-120/gram. Such a procedure presupposes that its value in LWR recycling is higher than that obtained in breeder reactors; in

other words, the electricity produced by a mixed simple LWR-plutonium reusing L WR system would be cheaper than that of a mixed simple LWR-FBR system.

But the experts then immediately state that it is not simply a question of this one set of assumptions because 'if FBRs are developed, the plutonium value will probably be higher than that obtained from plutonium recycling in LWR' . Such a method of calculation would thus be justified simply because the savings made are easier to calculate in L W R recycling.

The German and Belgian experi- ences in plutonium recycling in LWR reactors have demonstrated the extreme complexity of the reprocessing

and fabrication operations of mixed UO2 + PuO 2 fuel oxide. The fabrication cost alone would be 6-10 times greater than that of an LWR fuel element (6000-10000 francs against Ffl000/kg), completely making up the savings of Ffl20/grams of plutonium. (An extra fabrication cost of Ff3000/kg is needed on its own to make up this benefit, without taking account of extra reprocessing costs).

Finally, adding to the complexity of this topic, although plutonium recycling in LWR is considered in France to be something of a heresy by official bodies, they nevertheless use the use value of plutonium in such recycling to define plutonium price.

Appendix 2 Calculation of breakeven price of uranium Notation:

IB, CB = the investment cost (Ff/kW) and the fuel cost (cf/kWh) of FBRs

I b C L = the investment and fuel cost of LWRs in closed cycle without uranium expenses

N = number of discounted kWh produced during lifespan of reactors

Ap = increase in uranium price needed to make up for FBR electricity cost differential

We calculate the uranium price increase Ap in relation to the level of the

current price p. At equilibrium we will get

I B + C B = I ~ + C L + ct.Ap

(in cf/kWh)

or

1 1 , i / , Ap =~-~t B-L)+ CB'-CL

ct being a constant term needed to reach the uranium price calculated in Ff/kg, at the uranium cost worked out in kWh. To do this, it is assumed that one kg of fuel in a reactor will produce 240000 kWh during its time in the reactor. If the calculation is carried out in relation to the middle point of the

fuel's time-span in the reactor, the 6.5 kg of natural uranium required to fab- ricate this one kg are assumed to have been purchased 36 months before this date, ie 18 months before entering the reactor, from which

6.5 x 100 3.508 x 10 -3 a = 0.772 x 240000 =

0.772 being a discount term referring to 36 months. From this one deduces the breakeven price of uranium p + Ap taking an N of 56500 hours discounted. This corresponds to an annual load factor of about 72% (EDF assumption). We use the official discount rate of 9% in these calculations.

320 ENERGY POUCY December 1982

Appendix 3 Calculation of breakeven price of uranium when reprocessing is not considered a necessity Notation (we adapt the notation of Appendix 2):

C B = the total fuel cost of FBR (cf/kWh)

P ' = the cost of extraction of plutonium (Ff/g)

C' B = the cost of reprocessing and fabrication of FBR fuel (cf/kwh)

C' L = the fuel cost of LWRs in once- through cycle (cf/kWh) (without uranium cost)

R = the cost of LW R fuel reprocessing (Ff/kg)

P = the price of uranium (Ff/kg) A 1 = the cost of kWh produced by

LWR

A 2 = the cost of kWh produced by FBR

We have the following equations:

A1 IL = ~-+ C ' L + a . P

(Cost of LWR kWh)

IB+ A2 = ~- C'B + B.P'

(cost of FBR kWh)

R = y . P + 5.P '

(equilibrium of the LWR reprocessing activity)


The breakeven price of uranium is obtained by equalization of A 1 and A 2

~ + C'L + a.P = ~ + C'B + f3.P'

Therefore, to calculate P and P' , we have to solve a system of two equations with two unknowns.

IB IL -- C' c t . P - B.P' = ~ - - N + C' B L

P + 6 . P ' = R

Figure A1 could represent this procedure of calculation, and Table A1 gives the equilibrium cost of extraction of plutonium.

o

'5 A~

h J

O

"GE ~o.2 ~8 8

~ LWR

I ~ FBR I

~Breokeven price Price of luronium

I

Figure A1. Calculation of breakeven price of uranium (reprocessing unnecessary). Note: A = Equilibrium cost of electricity; B = Equilibrium cost of Pu.

Table A1. Equilibrium coet of ~ of plutonium taxi equiNbmJm a ~ t of kwh.

Case1 Case2 Caee3

Uranium breakeven price (S/It)) 173 265 335 Equilibrium cost of extnmtk~ of Pu

(Ff/g) 227 466 685 (S/g) 4o 7a 12o

Equilibrium cost Of LWR/FBR kWh (d/kWh) 21 25 29

(USe/kWh) 3.7 4.4 5.1

ENERGY P O U C Y December 1982 321

fast breeder reactors: the end of a myth?

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