Economics of symbiotic nuclear fleets at equilibrium

Many decades of industrial experience have proven that thermal reactors are able to provide a safe, reliable and competitive source of electricity. The higher construction costs of fast reactors compared to thermal reactors could be compensated by their better use of fissile material during the probable fast development of nuclear energy in the first half of the century. Thus, despite the over-cost of their cores, on the longer term, fast reactors are expected to take the lead in the nuclear reactor race. In the mean term, multi-strata symbiotic parks, using high conversion-rate thermal reactors, may delay fast reactor start up. We compare projected fuel cycle costs and cost of electricity of various symbiotic nuclear fleets, on the basis of a simple economic model and elementary costs estimated on publicly available data. These parameters and their evolution over reactor-life time scale can hardly be estimated. That is why we look at the sensitivities of our results to large modifications of the input parameters. The aim of our simple economic model is to understand which reactor characteristics should be optimized to enhance their economic performance when working as a single symbiotic fleet. (authors)