After about 30 years of operation, refurbishment can extend the life of a nuclear reactor for another 25 to 30 years. Refurbishment means modernizing and enhancing major equipment and systems.

The refurbishment of a nuclear power plant is similar to building a new facility — new standards and requirements apply.

Refurbishment also provides opportunities to enhance safety, and is part of the Canadian Nuclear Safety Commission’s (CNSC) approach to continuous safety enhancement.

As Canada’s nuclear regulator, the CNSC oversees all aspects of refurbishment projects — from the initial planning to when the reactor starts producing electricity again – to ensure it is all done safely.

Building on experience

The CNSC has extensive experience in regulating refurbishment projects, having gone through three major projects so far.

"The environmental assessment looks at the possible environmental impacts of both the refurbishment work itself and of the facility’s operation for several more decades."

During the refurbishment of a nuclear reactor, components such as feeder pipes and pressure tubes are replaced. Other components (like turbines and fuel handling equipment) can be restored and reused.

Thorough assessments

As part of the licensing process, several technical assessments must be completed before a refurbishment can be approved. Two key technical assessments are the integrated safety review and the environmental assessment.

An integrated safety review identifies possible improvements to safety systems. This is a rigorous and systematic process that looks at the reactor’s current state and compares it against modern standards, to identify what needs to be improved.

The environmental assessment looks at the possible environmental impacts of both the refurbishment work itself and of the facility’s operation for several more decades. The process is thorough and comprehensive. It includes studying potential impacts on water, animals, plants, air quality, and the public.

Before the CNSC allows a refurbishment to proceed, the plant operator must demonstrate — through this environmental assessment — that the environment and the health of Canadians are protected.

Return to service

Once all refurbishment activities are finished and inspections completed, the CNSC closely monitors the plant’s return to service, which is done progressively.

Some of the main steps that require approval before the plant can be restarted (to produce electricity again) include:  

  • loading fresh fuel in the reactor core
  • restarting the reactor
  • increasing the power level above 50 percent

Through each of these steps, the CNSC ensures that all required testing has been done properly, and that safety levels are met.