Advanced nuclear systems. Review study

The task of this review study is to from provide an overview of the developments in the field of the various advanced nuclear systems, and to create the basis for more comprehensive studies of technology assessment. In an overview the concepts for advanced nuclear systems pursued worldwide are subdivided into eight subgroups. A coarse examination raster (set pattern) is developed to enable a detailed examination of the selected systems. In addition to a focus on enhanced safety features, further aspects are also taken into consideration, like the lowering of the proliferation risk, the enhancement of the economic competitiveness of the facilities and new usage possibilities (for instance concerning the relaxation of the waste disposal problem or the usage of alternative fuels to uranium). The question about the expected time span for realization and the discussion about the obstacles on the way to a commercially usable reactor also play a substantial role as well as disposal requirements as far as they can be presently recognized. In the central chapter of this study, the documentation of the representatively selected concepts is evaluated as well as existing technology assessment studies and expert opinions. In a few cases where this appears to be necessary, according technical literature, further policy advisory reports, expert statements as well as other relevant sources are taken into account. Contradictions, different assessments and dissents in the literature as well as a few unsettled questions are thus indicated. The potential of advanced nuclear systems with respect to economical and societal as well as environmental objectives cannot exclusively be measured by the corresponding intrinsic or in comparison remarkable technical improvements. The acceptability of novel or improved systems in nuclear technology will have to be judged by their convincing solutions for the crucial questions of safety, nuclear waste and risk of proliferation of nuclear weapons. On the basis of the detailed analysis it is shown: a decisive qualitative progress in these latter fields can rather not be expected for the nuclear systems which would be realizable in the nearer future (5-15 years), while the longer-termed development projects (like fusion or accelerator driven systems) reach out fundamental improvements, however of which cannot be said, whether they are actually going to be realizable. A fundamental question is, how the level of scientific knowledge in the field of advanced nuclear systems can be assessed in regard to comprehensive technology assessment studies. An enduring evaluation of some of these aspects, like operational safety and economy, only becomes possible when corresponding nuclear systems have already been realized and sufficient operational experience has been acquired. This means, that the current level of scientific knowledge is not sufficient to come to a supportable conclusion. First attempts are being made in the present study to identify those knowledge gaps relevant for assessment. A significant extension of the examination pattern appears to be indicated for subsequent more comprehensive technology assessment studies on advanced nuclear systems. We therefore suggest an extended set of criteria, which is supposed to be suitable at first for the detailed examination, then for assessment and finally for the shaping of the various feasible scientific-technical options, where applicable. A basis for more detailed studies on advanced nuclear systems is created thereby