Dr. Paolo Contri
European Commission, JRC-Institute for Energy,
The Netherlands

"Research Priorities at the Joint Research Centre of the European Commission in Relation to Maintenance Optimisation and Nuclear Power Plant Life Management"

Due to current social and economical framework, in last years many Member States in the European Union started a process of Long Term Operation (LTO) for their older nuclear facilities. The process followed many different approaches, being intrinsically dependent on the national regulatory framework and technical tradition.

    This process has many nuclear safety implications, other than strategic and political ones, and therefore a need for tailoring the available safety assessment tools to such applications has become urgent in recent years.

    The analysis of the experience in the European countries operating Nuclear Power Plants (NPPs) suggested that most of the differences affecting the LTO programs are mainly related to the regulatory process (typically in the use of the periodic safety review), while the main components of the LTO program and its basic technical tasks are shared among most of the countries. There are differences in terminology, in responsibility, in scheduling, but the safety concerns are quite similar.

    Typical safety assessment processes such as the Periodic Safety Review has been used already and can be used in the future as a framework for an LTO. Also the review of regular maintenance and ageing management programs and the continuous upgrading of the Safety Analysis Report are tools widely used in LTO context in many Countries. However, most of these tools are rather general and in many cases they need reshaping in an LTO framework before application, with focus to the safety implications of the LTO. Their standard features, developed for plant still in their design life, need some modifications to support a long term decision.

    R&D tasks are needed in this phases, not only in the long term (i.e. more than 10 years of the standard Periodic Safety Review) extrapolation of the component integrity and behaviour, but a also in new management strategies at the plant, able to address organisational issues, spare part management, staff ageing, component obsolescence, etc.

    This paper aims at identifying the R&D tasks that could effectively support Plant Life Management Models (PLIM) at NPPs, more directly affecting the decision for a long-term safe operation of a nuclear facility. In particular the paper provides an analysis of the research actions already in progress at the European Commission-Joint Research Center (EC-JRC) and their preliminary results. A special chapter addresses the implementation issues recorded at some pilot plants, where site-specific research had to be developed for a successful application of the PLIM models.

    A priority list of research topics in relation to maintenance and PLIM is also provided, in compliance with the Framework Program 7 (FP7) – Euratom section - recently issued at the EC. 

References

• EUR 21903 EN, P.Contri et al., “Optimization of Maintenance Programmes at NPPs - Benchmarking study on implemented organizational Schemes, Advanced Methods and Strategies for Maintenance Optimization - Summary Report”
• EUR 22602 EN, P.Vaisnys et al., “Monitoring maintenance effectiveness using the performance indicators”
• EUR 22603 EN, P.Contri, Summary report on the workshop “Maintenance rules: improving maintenance effectiveness”, Petten, 2006
• EUR 22604 EN, V.Ranguelova, P.Contri, I.Kouzmina, Summary report on the Workshop on “Advanced Methods for Safety Assessment and Optimization of NPP Maintenance” Petten, 2006