Nuclear Power Plants

Aerial photograph of the Darlington Nuclear Generating Station located near Bowmanville, Ontario

Aerial photograph of the Darlington Nuclear Generating Station located near Bowmanville, Ontario

Nuclear power plants (NPPs) have been commercially producing electricity in Canada since the early 1960s. Today, 5 NPPs in three provinces house 22 nuclear power reactors, which have the capacity to generate more than 12,600 megawatts of power. Nuclear energy contributes about 15 percent of our country’s electricity.

All power reactors in Canada are CANDU reactors built using the Atomic Energy of Canada Limited design. CANDU reactors are pressurized heavy water reactors that use natural uranium as fuel and heavy water as a coolant and as a moderator.

The CNSC regulates an NPP’s entire life cycle through the Nuclear Safety and Control Act and its regulations. An NPP has five licensing stages:

  • site preparation
  • construction
  • operating
  • decommissioning
  • abandonment

CNSC licensing of NPPs is comprehensive and covers 14 separate topics referred to as safety and control areas (SCAs), such as radiation protection, emergency preparedness, environmental protection, and equipment fitness for service.

After a licence is issued, the CNSC monitors compliance. At each NPP, the CNSC has full-time staff who inspect operations and oversee activities on a day-to-day basis, to verify that licensees are complying with their regulatory obligations. CNSC staff with specific technical expertise also regularly visit NPPs to verify that operators are in compliance with regulatory requirements and licence conditions.

The CNSC carefully reviews any items of non-compliance and follows up to ensure all items are quickly corrected. Every year, it publishes a report on the safety performance of NPPs.

Locations of operating nuclear power plants in Canada

The image shows a map of Canada and indicates sites where nuclear power plants are located

The image shows a map of Canada and indicates sites where nuclear power plants are located:
Bruce A & B near Kincardine, Ontario, Pickering and Darlington near Toronto, Ontario, Gentilly-2
near Becancour, Quebec and Point Lepreau near St. John, New Brunswick.

Refurbishment and Life Extension

Workers at the Point Lepreau Generating Station inspecting the inside of an electrical generator

Workers at the Point Lepreau Generating Station inspecting the inside of an electrical generator

A CANDU NPP has a design life of approximately 30 years. After this time, major equipment and systems of the NPP need to be refurbished and revitalized.

As part of the planning to refurbish a facility and extend its operating life, the CNSC requires the operator to conduct an environmental assessment. This addresses substantial changes on site and includes a thorough review of the plant’s design, condition and operations against best national and international practices.

The operator must strive to modernize systems, structures and components to bring the safety of the facility to a level comparable to that of modern NPPs.

New Nuclear Power Plants

New NPP projects are being considered in some parts of Canada. When the CNSC receives such an application, its experts work in multidisciplinary teams to undertake an environmental assessment and a technical assessment, using the same 14 SCAs that will form the basis of any future licensing and regulatory oversight.

The CNSC now also offers pre-licensing vendor design reviews. A pre-licensing vendor design review is an optional review of a potential NPP design before the submission of an application for a licence to prepare a site for the construction of a new NPP.

Decommissioned Power Reactors

Douglas Point was located on the shoreline of Lake Huron near Kincardine, Ontario

Douglas Point was located on the shoreline of Lake Huron near Kincardine, Ontario

Three prototype nuclear reactors constructed and owned by AECL were shut down and prepared for decommissioning in the 1980’s in Rolphton and Kincardine, Ontario and Bécancour, Quebec. Today, the CNSC continues to license these facilities as waste management facilities. Funding to proceed with the decommissioning activities is provided by Canada’s Nuclear Legacy Liabilities Program.

In the future, all radioactive material will be removed and decommissioning will eliminate any unreasonable risks to health, safety, security and the environment. At this point, these facilities will be issued abandonment licences to release them from CNSC regulatory control.

Relevant Links