An Accurate Probabilistic Model for Estimating the Life Cycle Cost of Degrading Components in Nuclear Power Plants

Degradation of systems and components operating in harsh environment has an adverse effect on safety and reliability of nuclear power plants. Condition-based maintenance (CBM) programs are used to preventively maintain degrading components, which minimize the risk of failure. However, maintenance programs can be costly due to frequent inspection, increased outage time, and redundant maintenance of functional components. The optimization of maintenance programs over the life cycle of systems is an important issue for the plant managers. The paper presents an advanced model for the evaluation of life cycle cost of degrading components in the nuclear plants, which can be used for the maintenance optimization. The proposed model is based on the more precise finite time horizon formulation, instead of using asymptotic formulae that may lead to inaccurate results in practical settings.