THORIUM AS AN ENERGY SOURCE - Opportunities for Norway ...

Economical Aspects
conventional reactor (for instance with the possible elimination of control rods) may be offset by
cost increases related to complications in containment and other systems. The basic construction
cost for an ADS was therefore set equal to that for a FR with an addition to cover capital costs of
accelerator and target. The study also concluded that “Fuel cycle schemes that involve the use of
the more expensive ADS technology show an overall economic benefit by burning as much of the
plutonium as possible in less expensive more conventional systems, i.e. MOX-LWRs and MOX-
FRs”.
Since then, experts participating in different OECD/NEA standing technical committees or
working groups have regularly concluded that energy production with an ADS cannot compete
economically with critical reactor technology.
From an economic point of view, the complexity of ADS technology and the inescapable problems
of technological development and definition of the safety features cast doubt on the particularly
low future costs estimated by its promoters; about 30 % lower for a unit in the series already
planned by the CERN group (Carlo Rubbia, 1996 [158]) compared with the costs (in USc/kWh) for
a serial PWR in France announced in 1996 by Fernandès et al. Until successive units have
actually been built and safety standards have been met, any estimate of this kind is bound to call
to mind the extremely optimistic estimates of the investment cost of the nuclear kWh made in the
1960s (3 to 400 $/kW current value compared with 2500 $/kW effective cost) which widely
underestimated technological problems. The extra costs involved in the addition of an accelerator
compared with a present reactor should be compensated by the possible advantages of the
potential simplicity of the subcritical reactor and a simpler fuel cycle. The present state of
knowledge and technological know-how on the concepts to be explored is still insufficient. A
certain number of projects are at the laboratory or the small pilot stage. None can provide a
standard in terms of demonstration equipment. Complete industrial proficiency with respect to
the new technological system will necessitate skills in numerous techniques and a long
operational period will be necessary to demonstrate the feasibility of multi-recycling, something
which has so far never been achieved for any nuclear reactor. At the same time, regulations to
guaranty safety standards comparable to those of light water reactor technology by the protype
stage must be gradually determined and will require often costly technological adaptation.
Altogether, the main challenges to develop a thorium based energy production might be the
mobilization of the funding necessary to carry out the needed research and development for both
the energy production technology and the associated fuel cycle. This research and development
can not be done by Norway alone and should be seen in a European context. What concerns
thorium-based energy production, one of the projects of the Generation IV International Forum
would be well suited and for the back-end of the thorium fuel cycle, a European XT-ADS
experiment leading to a demonstration of an ADS would be appropriate. The financial
contributions to these projects would depend on the desired Norwegian involvements.
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