It is still owned by Ontario Power Generation, a publicly owned electrical generation company.
The plant is located at 440 Unwin Avenue in Toronto's Port Lands area, directly south of the foot of Carlaw Avenue, across the shipping channel and next to the recently opened Portlands Energy Centre. Hearn Generating Station, together with the nearby Ashbridges Bay Wastewater Treatment Plant sewage sludge incinerator stack and the Commissioners Street waste incinerator stack, stand as towering landmarks of a bygone industrial era in the Portlands area of Toronto (all three facilities are no longer in operation, but their towering smokestacks still stand).
In October 1985, Premier David Peterson's Liberal government proposed the re-opening the station using natural gas.
Work on the restart was well underway when the new New Democratic Party government of Premier Bob Rae cancelled the project.
The station at first had four smaller chimneys, one for each of the four boilers.
The construction of the four units added four more chimneys.
The last three were a bit taller than the first five.
The eight short chimneys were a source of air pollution in local neighborhoods and downtown Toronto and also fly ash and other particulates. The eight chimneys were demolished and electrostatic precipitators were added for the units when the large smokestack was built.