Nuclear Power Engineering

Plant Life Management for Safe Long Term Operation

Plant Life Management Planning

For the past couple of decades there has been a change of emphasis in the world nuclear power from that of building new Nuclear Power Plants (NPP) to that of taking measures to optimize the life cycle of operational plants. National approaches in many countries showed an increase of interest in Plant Life Management (PLiM) for safe long term operation, both in terms of plant service life assurance and in optimizing the service or operational life of NPP.

The safety considerations of a NPP are paramount and those requirements have to be met to obtain and to extend/renew the operating license. To achieve the goal of the long term safe, economic and reliable operation of the plant, PLiM programme is essential. Some countries already have advanced PLiM programmes while others still have none. The PLiM objective is to identify all those factors and requirements for the overall plant life cycle. The optimization of these requirements would allow for the minimum period of the investment return and maximum of the revenue from the sale of the produced electricity.

Recognizing the importance of this issue and in response to the requests of the Member States the IAEA Division of Nuclear Power implements the Sub-programme on "Engineering and Management Support for Competitive Nuclear Power". Three projects within this sub-programme deal with different aspects of the NPP life cycle management with the aim to increase the capabilities of interested Member States in implementing and maintenance of the competitive and sustainable nuclear power.


Although all three projects contain certain issues of PLiM, there is one specific project on guidance on engineering and management practices for optimization of NPP service life. This particular project deals with different specific issues of PLiM including aspects of ageing phenomena and their monitoring, issues of control and instrumentation, maintenance and operation issues, economic evaluation of PLiM including guidance on its earlier shut down and decommissioning.

Plant life management (PLiM) is the process by which nuclear power plants integrate their operations, maintenance, engineering, regulatory, environmental, and economic planning activities in order to manage the material condition of a plant (ageing and obsolescence of systems, structures and components), optimize plant operating life (and consider the options of early plant retirement as well as licence renewal and plant life extension), and maximize plant value while maintaining plant safety.

The benefits of PLiM planning are:

  • To identify components that are critical to plant safety and power generation

  • To identify ageing degradation mechanisms that can lead to an unexpected/unplanned functional failure

  • To provide opportunities for value creation through consideration of the effects of alternative operation and maintenance practices

  • To provide financially optimized, long-term ageing management plans

  • To optimize reliability, availability, capacity factor, O&M cost, capital cost and staffing

  • To integrate these to achieve: lowest cost/kWh while maintaining safe operation over the life of plant

The IAEA develops international guidance to improve PLiM programmes for long term operation and delivers training, technical assistance and equipment to Member States.

Please contact NENP Engineering Section - Contact Point if you have any questions.