Development of a support system to make economic and technical assessments for the issues relating to plant life extension

To realize the life extension of nuclear power plants, overall evaluation for the plant is required, which covers technology, economy such as cost of repair or/and replacement of components, and regal regulations for licensing. A prototype of integrated assessment support system for life extension ''INPLEX'' have developed in order to evaluate the technical and economic issues relating to the plant life extension and to make a life extension scenario. Analysis procedure of INPLEX is as follows. A comparison of the cost between the life extension and the reconstruction is made to see whether the life extension is cost effective or not. Next, components required detailed assessments are selected, and the residual life assessment of these components are made. After those procedures life extension measures are selected and the implementation time schedule is set on the basis of the formulas for predicting the degradation of the components and the component reliability data. Finally the implementation time schedule is optimized from the viewpoint of economy, and the life extension scenario is proposed. INPLEX also has the data base ''PRINS'', in which information and data related to life extension are registered, such as component degradation experiences, degradation management methodologies, degradation mitigation measures, and so on. PRINS can be referred at any time during the operation of INPLEX