Short answers, pulled from the story.
Ontario Power Generation (OPG) is a Crown corporation wholly owned by the government of Ontario. It is responsible for approximately half of the electricity generation in the province of Ontario, Canada, drawing from nuclear, hydroelectric, wind, gas, and biomass sources.
OPG was established in April 1999 as part of the Progressive Conservative government of Premier Mike Harris's plan to privatize Ontario Hydro's assets and deregulate the provincial electricity market. It became one of five successor corporations to Ontario Hydro and assumed ownership of all generating stations.
OPG owns four nuclear power plants: Pickering Nuclear Generating Station in Pickering, Darlington Nuclear Generating Station in Courtice, and the two plants that make up the Bruce Nuclear Generating Station on Lake Huron. OPG directly operates Pickering and Darlington; Bruce is operated by Bruce Power under a long-term lease.
The refurbishment of Unit 4 at the Pickering A Nuclear Station came in significantly over budget and three years behind schedule. In late 2003, the incoming Liberal government fired OPG's three most senior executives and accepted the resignation of the entire board of directors. An independent review committee chaired by former federal Finance Minister John Manley was established to examine the company's future.
OPG shut down the Nanticoke and Lambton generating stations and converted two others: the Atikokan Generating Station was converted to biomass in 2012, and the Thunder Bay Generating Station converted to advanced biomass in 2014. The last coal was burned at OPG's stations in 2014, seven years after the Liberal government's original 2007 target.
OPG announced in February 2023 that it would purchase the former General Motors of Canada head office building at 1908 Colonel Sam Drive in Oshawa, Ontario, for its new headquarters, with full occupancy now expected by the end of 2025. An earlier plan to build a new campus in Clarington, Ontario, was abandoned for economic and sustainability reasons.