At a glance
OPG has started redevelopment of its Coniston, Stinson, and Matabitchuan hydroelectric generating stations.
The three stations have safely and reliably served Ontario for a century or more, playing a key role in early development of industry.
These sites will continue to generate low-carbon power for Ontario for approximately 80 to 90 more years.
OPG’s 120-year-old Coniston Generating Station is situated east of Sudbury.
OPG is now redeveloping three of its oldest hydroelectric generating stations to secure more low-carbon, reliable power for the province’s future.
More than a century ago, OPG’s Coniston, Stinson, and Matabitchuan stations played a key role in supporting burgeoning communities in the north and the expansion of Ontario’s economy.
The reliable electricity from these facilities helped power Ontario’s early mine operations—including nickel, silver, and cobalt—as well as the logging industry.
Now, these long-lived plants are being redeveloped to ensure they can support Ontario’s next chapter of growth and electrification.
Just east of Sudbury on the Wanapitei River, OPG is moving into the execution phase for the redevelopment of the 120-year-old Coniston and 100-year-old Stinson Generating Stations (GS). Once complete, these plants will have a combined generating capacity of approximately 12 megawatts (MW), an increase from the current stations’ approximate combined 8 MW output.
And further northeast, OPG is now mobilizing to redevelop its four-unit Matabitchuan hydro station, which has been safely producing power for Ontario for 115 years. Located about 40 kilometres southeast of Cobalt, the new facility will see a bump in output to 12 MW from the current station’s 7.5 MW.
Once complete, these projects will ensure continued safe and reliable operations at these sites for approximately an additional 80 to 90 years, while increasing generating capacity.
Building on a strong legacy of renewable generation
Coniston GS was built in 1905 and has a storied past. In 1952, a dramatic fire caused by two bolts of lightning led to extensive damage and a four-month closure for the plant. The station returned to half-power operations later that year and was fully rehabilitated by 1955.
Originally commissioned with three units, two of Coniston’s units have been permanently shut down after reaching their end-of-life. Its final unit has now also gone offline for the redevelopment.
OPG's 100-year-old Stinson Generating Station.
Meanwhile, Stinson GS was built in 1925 upstream of Coniston. The facility has two generating units with a total output of about 5.4 MW.
The stations’ redevelopment will include the demolishment of the existing powerhouse buildings to their foundations, as well as a complete teardown of associated mechanical and electrical systems. New structures and more efficient generating units will be constructed in their place.
“With 100 years of energy production, Stinson GS is a testament to the rich history of care contributing to longevity of these assets,” said Sheldon Masson, OPG’s Senior Manager of Maintenance and Production for the North Bay/Coniston area. “OPG’s plan to redevelop existing stations goes hand in hand with our commitment to the people of Ontario in electrifying life in one generation—and Stinson’s redevelopment will help to meet these goals.”
Matabitchuan GS will see similar redevelopment work taking place over the next three years.
In addition to two new modern units that will increase output by approximately 4.5 MW, Matabitchuan’s existing powerhouse will be demolished and replaced with a new structure featuring an optimized, modular design that will help minimize cost and schedule impacts by reducing the powerhouse’s footprint.
For all three projects, OPG has continued to engage with the public and local Indigenous communities. Through public and community open houses, employment open houses, and one-on-one outreach, OPG is committed to fostering collaboration and ensuring these redevelopments involve consultation from the communities they will serve.
Learn more about OPG’s hydroelectric operations here.
OPG's Matabitchuan Generating Station has been producing power for Ontario for 115 years.
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