Darlington Nuclear Generating Station is a Canadian nuclear power plant located on the north shore of Lake Ontario in Clarington, Ontario. The facility derives its name from the Township of Darlington, the former name of the municipality in which it is located. The Darlington station is a large nuclear facility and comprises 4 CANDU nuclear reactors located on the northern shore of Lake Ontario, having a total output of 3,512 MWe (capacity net) when all units are online. It provides about 20 percent of Ontario's electricity needs, enough to serve a city of two million people. It is arguably one of the most advanced nuclear generating stations in the world.

Darlingtong Nuclear Power Plant Construction and Operation

The facility was constructed in stages between 1981–1993 by the provincial Crown corporation, Ontario Hydro. Unit 2 was brought online in 1990, Unit 1 in 1992, and Units 3 and 4 in 1993. In April 1999 Ontario Hydro was split into 5 component Crown corporations with Ontario Power Generation (OPG) taking over all electrical generating stations and which continues to operate the Darlington station.

To most Ontarians, the Darlington station is associated with the massive cost overruns incurred during its construction. The initial cost estimate for the station was $3.9 billion CAD in the late 1970s, while the final cost was $14.4 billion CAD. The project was adversely affected by declining electricity demand forecasts, mounting debt of Ontario Hydro, and the Chernobyl disaster which necessitated safety reviews in mid-construction. A year-long period of public hearings and study by an Ontario government all-party committee finished in 1986 with the decision to proceed with the project, which had then risen to $7 billion in actual and committed costs. Discussion of who is to blame for the costs and subsequent debts associated with Darlington often arise during provincial election campaigns, and are often mentioned in anti-nuclear literature. The Darlington reactors have been among the best performing in OPG's CANDU fleet, including a top year in 2008 in which the plant achieved a combined 94.5% capacity factor.

The reactors are as follows:



New build proposal

OPG has also begun the process for building up to 4 new nuclear units at the site of its Darlington Nuclear Station. There is a lengthy approvals process in place including a full Environmental Assessment which will take 3–4 years to complete. If successful, the new units would go into service sometime around 2018. No decision has been made on what technology will be used.

In June 2009, the government of Ontario rejected all three bids submitted, leaving the status of the new builds up in the air.


The Darlington Waste Management Facility provides dry storage for the used fuel from Darlington, after an initial period in a water-filled storage bay. The facility was opened in 2007, reportedly on schedule and on budget. Ontario has proposed the construction and operation of a Deep Geologic Repository in Kincardine, Ontario for the long-term storage of low and intermediate level nuclear waste on lands adjacent to the Western Waste Management Facility in Kincardine, Ontario. Pending approvals and licensing by regulatory agencies, the DGR will commence construction in 2012 and operation in 2017/2018.

Darlingtong Nuclear Power Plant Awards and Recognition

2008: International Corporate Habitat of the Year Award (Wildlife Habitat Council)

2007: Performance Improvement Award (Institute of Nuclear Power Operators)

2007: 20th Anniversary Signatures of Sustainability Award (Wildlife Habitat Council)

2005: International Corporate Habitat of the Year Award (Wildlife Habitat Council)

Darlington Nuclear Generating Station
Country Canada
Locale Clarington, Ontario
Coordinates 43°52′22″N 78°43′11″W / 43.87278°N 78.71972°W / 43.87278; -78.71972Coordinates: 43°52′22″N 78°43′11″W / 43.87278°N 78.71972°W / 43.87278; -78.71972
Status O
Construction began 1981–93
Construction cost $14.4 billion CAD
Operator(s) Ontario Power Generation (OPG)

Reactor information
Reactors operational 4
Reactors operational (MW) 3,512
Reactor types CANDU