Ontario Power Generation
Pickering Nuclear
Located on the shores of Lake Ontario just east of Toronto and nestled in the community of Pickering, is one of the world's largest nuclear generating facilities consisting of the Pickering A and Pickering B Nuclear Generating Stations.
Pickering A has two operating CANDU (CANadian Deuterium Uranium) reactors and Pickering B has four operating CANDU reactors. Together these stations have a total output of 3,100 megawatts (MW), enough to serve a city of one and a half million people.
Pickering A - the first four of the Pickering reactors - went into service in 1971 and continued to operate safely until 1997 when it was placed in voluntary lay-up as part of what was then Ontario Hydro's nuclear improvement program. In September 2003, Unit four, was returned to commercial operation. Unit 1 was returned to commerical operation in November 2005. Units 2 and 3 remain in a safe shutdown state.
Pickering B - units five, six, seven and eight - continue to operate safely since they were brought into service in 1983. They have a combined capacity of approximately 2,100 megawatts. OPG has begun the Pickering B Refurbishment Study to determine the feasibility of refurbishing the units at Pickering B in order to extend their operating lives until 2050-2060.
The Pickering Stations A and B produce electricity with heat created by nuclear fission using natural uranium fuel.
The heat produced by this reaction is transferred, via a separate heavy water heat transport system to boilers where ordinary water is boiled and the resulting steam is used to drive a turbine generator that produces electricity. This electricity is fed into transmission lines that carry the power from the site to residential, commercial and industrial users. The CANDU technology, developed in Canada, enables Pickering to produce its enormous electrical output by nuclear fission using natural uranium fuel for a whole year with no more fuel than would fill a two car garage.
Safety
Safety was the key consideration that guided the design and construction of this station. The CANDU system includes several ways to safely shut down our reactors and in the unlikely event of a serious incident, the multiple barrier safety system will prevent any harmful release of radiation. The Pickering station is licensed by the Canadian Nuclear Safety Commission which regulates the use of nuclear energy and materials to protect health, safety, security and the environment through the Nuclear Safety and Control Act. In addition, the station is subject to other federal and provincial government safety and environmental regulations such as the Environmental Protection Act and the Planning Act. Pickering meets or surpasses all the prescribed regulations.
Pickering A and Pickering B are very similar in structure and facilities.
Reactor Buildings
The four cylindrical structures in each of the Pickering A and B stations are made of heavily reinforced concrete to enclose the reactors and related equipment. Interior concrete walls also shield personnel from radiation during operation. Each building contains one reactor and 12 steam generators (boilers). The reactor consists of a large, heavily shielded vessel or calandria. In Pickering A the calandria in each reactor unit consists of 390 pressure tubes. The calandria in the Pickering B units consist of 380 pressure tubes.
The Turbine Buildings
These two steel frame structures, approximately 382 m (1,255 ft.) long, 54 m (179 ft.) wide and 45 m (148 ft.) high, each contain four turbine generators and their associated equipment. Each turbine generator has a single shaft rotating at 1,800 rpm.
Vacuum Building
This 51 m (166 ft.) high cylindrical concrete structure is connected to the eight reactor buildings by a pressure relief duct and is a unique safety feature of the CANDU system. The vacuum building is maintained at negative atmospheric pressure. Any release of radioactive steam from the pressurized systems would be sucked into the vacuum building, thus preventing its release outside the station.
Pickering B
Learn more about the Pickering B refurbishment study.
Community Connection
Find out more about all the ways Pickering Nuclear is making a difference in your community.