Andreev reported in 2013 that thorium-based nuclear fuel is thought to play a variety of roles depending on a particular nuclear energy system, which makes it challenging to form judgments regarding the economic prospects of thorium. Assessments of the costs and merits of individual elements of a thorium technological cycle are directly contingent on the choice of the fuel cycle and the various technological solutions involved – solutions that as yet do not exist. Furthermore, there is a scarcity of reliable data on the costs of thorium-based nuclear energy systems, and conclusions often have to be drawn based on expert evaluations or data obtained indirectly.
In principle, thorium fuel can be used in a rather broad range of nuclear reactor types – practically in all the existing designs and a number of those under development. Economic assessments of a thorium fuel cycle vary considerably depending on whether thorium is suggested for use in reactor types that are already in operation in the nuclear energy industry or whether prospective designs are meant (these would imply, first and foremost, molten salt reactors and accelerator-driven subcritical reactors).
In the case of the former, the author deals with developed technologies, which, under certain conditions, would allow the substitution of thorium fuel for traditional fuel. These may be both light water and heavy water reactors. The latter will be nuclear energy systems developed specifically for a thorium fuel cycle. In this case, it is only possible to make rather basic assumptions regarding such development trends that promise lower costs compared to traditional
nuclear energy technologies. The potential economic advantages of thorium-based fuel cycles stem directly from the peculiarity of thorium as a nuclear fuel.
Firstly, there exists – though so far, it is yet to be technologically implemented – the principal possibility of creating a thorium fuel that will generate more uranium-233 in thermal reactors than will be consumed. The fissile breeding potential is a unique characteristic of thorium fuel, something that cannot be achieved using fuel based on uranium.
Secondly, to initiate reaction, thorium-based fuel can use as driver fuels slightly enriched uranium or highly enriched uranium, recycled uranium from light water reactors, or reactor-grade or weapons-grade plutonium. Application of thorium-based fuels would mean both plutonium and transuranium elements could be burned, which has immense significance from the point of view of management of radioactive waste.
The author concluded that the economics of thorium-based nuclear energy are as yet quite speculative. So far, one can offer but “guesstimates” as to the
likely cost of thorium-produced energy as compared to that of energy derived from uranium. The value of this or that nuclear material depends on the process flow that it forms part of. If it is a material with potential use in an actually existing nuclear fuel cycle, it is assessed based on the cost of materials
it is capable of replacing, adjusted for the larger or smaller cost at which it is procured.
If, on the other hand, a fundamentally different fuel cycle is under consideration, then the comparison must be made with the existing fuel cycles on the whole, with waste management, safety, insurance, and other costs taken into account. The choice of one or another nuclear energy development strategy affects alleconomic indicators at once, therefore, comparing specific cost items is generally not very practical. At each stage, and for the entire system on the whole, the cost minimization tasks are approached depending on the multidirectional impacts that a variety of factors have on the costs.
The main economic advantages of thorium reactors do not apparently lie in the cheaper energy that they produce, but rather in the lesser cost of management of spent fuel generated by conventional, uraniumbased nuclear reactors. For instance, in its 2010 report [NNL (2010)], the UK National Nuclear Laboratory said it believes that the thorium fuel cycle does not currently have a role to play in the UK context, other than its potential application for plutonium management in the medium to long term. The technology is innovative, although technically immature and currently not of interest to the utilities, representing significant financial investment and risk without notable benefits. In many cases, the benefits of the thorium fuel cycle have been overstated.
Managed & Built by I2M Consulting, LLC | © 2010-
