The main argument offered for the DAE’s pursuit of breeder reactors is that India has only "modest uranium reserves" of approximately 60,000 tons, "which can support 10 000 MWe (megawatt electric) of PHWR (pressurized heavy-water reactor) capacities".34 While widely repeated, this formulation is misleading. India’s uranium resource base cannot be represented by a single number. As with any other mineral, at higher prices it becomes economic to mine lower grade and less accessible ores. Exploiting these would increase the amount of uranium available. Therefore, uranium resources can only be specified as a function of price.

As a way of evaluating the economics of breeder reactors, the cost of generating electricity at the 500 MWe PFBR can be compared with that at the PHWR,35 the mainstay technology of the Indian nuclear program.36 In order to address the argument about India’s limited uranium reserves, it must be understood that the reserves are a function of uranium price, which allows calculation of the crossover price when the two technologies generate electricity at the same cost.

The total construction cost of the PFBR is estimated as Rs. 34.92 billion (mixed year Rupees; overnight construction cost of $646 millions in 2004 dollars). The overnight unit cost is $1292/kilowatt (KW) and is lower than the corresponding figure for recent Indian PHWRs of $1371/KW. This is quite in contrast to experiences around the world that suggest that breeder reactors are much more expensive than water moderated reactors; for light-water reactors, a typical estimate of the minimum cost difference is $200/kilowatt electric (KWe).37 The PFBR’s estimated construction cost is also much lower than estimates of breeder reactor construction costs elsewhere; the Nuclear Energy Agency (NEA) gives a range of $1850-2600/KWe ($2000) or $2000-2800 (2004 dollars) for mixed-oxide fueled (MOX) fast reactors.38 Actually constructed breeder reactors in other parts of the world also bear out the expectation of higher costs. Construction costs for the French Phenix reactor with a capacity of 250 MWe totalled $800 million in 1974 French FRF ($800 million in 2004 dollars) or $3200/KW. However, a further €600 million ($870 million in 2004 dollars) were spent on Phenix upgrades between 1997 and 2003. The 1240 MWe Superphenix was even more expensive. For these technical reasons, and the DAE’s history of cost overruns at all the reactors it has constructed, it is likely that the PFBR capital cost will be higher than this projected value.39

In economic terms, the primary material requirement for the PFBR is plutonium. The PFBR design requires an initial inventory of 1.9 tons of plutonium in its core.40 Based on a detailed model of the reactor, it has been estimated that at a 75 percent capacity factor, the PFBR requires 1012 kg of plutonium every year for refueling during equilibrium conditions.41 The plutonium for the initial core and the first few reloads will have to come from reprocessing of PHWR spent fuel. At a real discount rate of 6 percent, reprocessing costs approximately $659 per kg of uranium in the fuel, which corresponds to a plutonium cost of $178/g.42 Because of the higher plutonium content of the PFBR spent fuel, the unit cost of subsequent plutonium requirements would be lower, approximately $43/g.43

Following the Nuclear Energy Agency, the costs of fabricating breeder reactor core fuel and (radial) blanket uranium fuel have been assumed to be $1512/kg and $540/kg.44 The base case assumes costs of $200/kg for natural uranium and $200/ kgU for fabrication of uranium fuel for heavy-water reactors. The high base costs of uranium reflects the higher mining costs of poor quality uranium ore in India

Table 3.3 shows the difference in the levelised cost, at a real discount rate of 6 percent, of producing electricity at the PFBR and at the proposed 2 x 700 MW twin unit PHWRs.45 The economics of the PFBR will be key to the future of breeder reactors in India. The DAE has argued that the "primary objective of the PFBR is to demonstrate techno-economic viability of fast breeder reactors on an industrial scale".46 The results presented here show that the PFBR will not be viable, even at the projected costs and for optimistic assumptions about capacity factors. As table 3.4 shows, breeder reactors across the world have operated with relatively low cumulative load factors. There is no reason to expect that the PFBR experience

would not be similar, and a capacity factor of 50 percent might well be more plausible. This would result in a levelised cost of 8.35 cents/kilowatt hours (kWh), 139 percent more expensive than PHWRs.

As mentioned earlier, the main rationale offered for the pursuit of expensive breeders is the shortage of uranium. The validity of this rationale has been examined by increasing the price of uranium from $200/kg to the crossover value where breeders become competitive. For the optimistic base case, with a PFBR capacity factor of 80 percent, the levelised costs of electricity from the PFBR and PHWR are equal at a uranium price of $1375/kg. At a PFBR capacity factor of 50 percent, the crossover price is $2235/kg

These prices are much higher than current values and significantly larger quantities of uranium will be available at these prices. The distribution of uranium among the major geological reservoirs in the earth’s crust corresponds to a roughly three hundred fold increase in the estimated amount of recoverable uranium for every ten fold decrease in the ore grade.47 Based on this, and assuming that mining cost is inversely proportional to ore grade, one can surmise that the available uranium at costs less than $1375/kg and $2235/kg are approximately 124 and 417 times current reserves respectively. This is an underestimate because it ignores the general trends of reduced mining costs due to learning and improved technology.48 In any case, India should have sufficient uranium for a nuclear energy sector based on PWHRs for many decades, with no reprocessing and breeder reactors.

Plutonium for weapons?

There may be another reason for the DAE’s attraction to breeder reactors. This stems from the source of DAE’s institutional clout: its unique ability to offer both electricity for development and nuclear weapons for security. This was revealed quite clearly during the course of negotiations over the U. S.-India nuclear deal, where in an ostensibly civilian agreement, much of the DAE’s efforts were aimed at optimizing its ability to make fissile material for the nuclear arsenal within various constraints, especially the shortage of domestic low-cost uranium.49 Most prominently, the DAE focused a lot of attention on keeping the fast breeder program outside of safeguards. In a prominent interview to a national newspaper, the head of the DAE said:

Both, from the point of view of maintaining long-term energy security and for maintaining the minimum credible deterrent, the fast breeder programme just cannot be put on the civilian list. This would amount to getting shackled and India certainly cannot compromise one (security) for the other.50

In parallel, the DAE did not classify its reprocessing plants or its stockpile of reactor-grade plutonium as civilian. This allows for the possibility that breeder reactors like the PFBR could be used as a way to launder unsafeguarded reactor-grade plutonium, both in the historical stockpile as well as from future production at unsafeguarded reprocessing plants, into weapon-grade plutonium. While reactor — grade plutonium is consumed in the core of the PFBR, weapon-grade plutonium is produced in the radial and axial blankets. Based on neutronics calculations for a detailed three-dimensional model of the reactor, it has been estimated that 92.4 kg and 52 kg of weapon-grade plutonium will be generated in the radial and axial blankets (93.7 percent and 96.5 percent plutonium-239) respectively in the PFBR each year at a 75 percent capacity factor.51

If the blanket fuel elements are reprocessed separately rather than jointly with the core fuel elements, then the plutonium contained in them can be used for weapons. To make up for this, approximately 346 kg of reactor-grade plutonium derived from reprocessing spent fuel from India’s PHWRs would have to be used in the PFBR annually. The existing stockpile of reactor-grade plutonium and PHWR spent fuel is adequate to meet this need for decades. Such a strategy would increase the DAE’s weapon-grade fissile material production capacity several-fold.

Future projections

The PFBR is to be the first of the many breeder reactors that the DAE envisions building. The DAE’s current projections are that nuclear power would grow to 20 gigawatt electric (GWe) by 2020 and to 275 GWe by 2052, including 260 GWe in metallic fueled breeders.52 More recent media statements following the nuclear suppliers group lifting of its ban on nuclear trade with India project even larger rates of growth of India’s breeder capacity. These projections seem to assume that spent fuel from imported light-water reactors fueled with imported uranium will be reprocessed and the plutonium extracted will also be used to provide startup fuel for breeder reactors.

These projections are primarily based on assumptions about the doubling time, the time it would take a breeder reactor to produce enough plutonium to fuel a new breeder reactor core. Since MOX fueled reactors have lower breeding ratios, by 2020 the DAE plans to switch to constructing breeders that use metallic fuel, which could have a much higher breeding ratio.53 A higher breeder ratio will result in a shorter doubling time. The rate of growth also depends sensitively on the out-of-pile time, the time period taken for the spent fuel to be cooled, reprocessed, and fabricated into fresh fuel. The DAE optimistically assumes that all of this can be accomplished within one year.54

The DAE’s methodology is flawed, however, and does not account correctly for plutonium flows.55 To start with, the base capacity of metallic fueled breeder reactors (MFBRs) assumed for 2022 of 6 GWe, which is necessary for the 2052 projection, would require approximately 22 tons of fissile plutonium for startup fuel. The DAE does not have enough reprocessing capacity currently to handle all the spent fuel produced by the heavy water reactors that are operating and under construction. Even if the DAE does manage to inexplicably obtain the necessary plutonium to construct a MFBR capacity of 6 GWe with some to spare, under the DAE’s assumed rate of growth, the plutonium stockpile would decline by approximately 40 tons just in the first ten years, even with an optimistic one year out of pile time. This is due to a three year lag between the time a certain amount of plutonium is committed to a breeder reactor and additional plutonium, which could be used as startup fuel for a new breeder reactor, is produced by reprocessing the irradiated spent fuel containing the initial plutonium.

A more careful calculation that takes into account the plutonium flow constraints shows that the capacity for MFBRs based on plutonium from the DAE’s heavy water reactor fleet will drop from the projected 199 GWe to 78 GWe by 2052.56 If the out-of-pile time were projected to be a more realistic three years, the MFBR capacity in 2052 based on plutonium from PHWRs will drop to 34 GWe.

While these figures may seem large compared to India’s current nuclear capacity of only 4.1 GWe, they should be viewed in relation to the projected requirements, under business-as-usual conditions, of approximately 1300 GWe total generating capacity by mid-century. Further, the only constraint assumed here is fissile material availability. It assumes that there will be no delays due to infrastructure and manufacturing problems, economic disincentives due to the high cost of breeder electricity, or accidents. All of these are realistic constraints and render even the lower end of the 2052 projections quite unrealistic.

Conclusion

Breeder reactors have always underpinned the DAE’s claims about generating large quantities of cheap electricity necessary for development. Today, more than five decades after those plans were announced, that promise is yet to be fulfilled. As elsewhere, breeder reactors are likely to be unsafe and costly, and their contribution to overall electricity generation will be modest at best.