Rio Tinto Prioritizing $1.2B Upgrade to Quebec Hydro Powering Aluminum Production

    May 19, 2025
    The Isla Maligne hydro plant powers lower carbon aluminum at the company's operations in Saguenay-Lac-Saint-Jean. The work will focus on replacing eight turbine-alternator groups, rehabilitating water intake and hydraulic passage, replacing electrical and mechanical equipment and modifying a spillway to perform more reliably in winter.
    Isla-Maligne hydroelectric plant image credit Rio Tinto website
    682b59814af3574989589d9f Rio Tinto Hydro

    Global mining and metals producer Rio Tinto will spend $1.2 billion to modernize a 99-year-old Canadian hydroelectric plant which powers its aluminum production in Quebec.

    The Isle-Maligne hydroelectric plant in Alma, Quebec, was first commissioned in 1926. The Rio Tinto capital expenditure on power upgrade will be the company’s biggest there since the 1950s, according to reports.

    Aluminum refinery image credit Rio Tinto website
    rio_tinto_refinery

    Rio Tinto prioritizes the 448-MW Isle-Maligne hydro power plant as essential for aluminum production in Saguenay-Lac-Saint-Jean. The aluminum hub there includes a refinery, five smelters, research and development facilities, an operations center and the hydropower capacity.

    The aluminum production at Quebec averages close to 1.5 million metric tons per year and accounts for a significant portion of the company’s global output.

    “The Isle-Maligne hydroelectric power plant has been a strategic asset for Rio Tinto for 100 years, drawing on the expertise and dedication of multiple generations of employees and business partners,” Sébastien Ross, Rio Tinto’s aluminum managing director for Atlantic operations, said in a statement. “This major investment to modernize our facilities will ensure the long-term future and competitivity of our low carbon aluminium production in Quebec for decades to come for our Canadian and American customers.’’

    The Isla-Maligne hydropower modernization project will take until 2032 to complete, the company says. The work will focus on replacing eight turbine-alternator groups, rehabilitating water intake and hydraulic passage, replacing electrical and mechanical equipment and modifying a spillway to perform more reliably in winter.

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    Some 300 workers will be committed to the project. Rio Tinto previously announced another $183 million to refurbish butterfly valves and work on two other turbine-alternator groups at Isle-Maligne.

    Seven of the eight hydroelectric plants within the Isle-Maligne complex are dedicated to providing power for low-carbon smelter operations, while the remaining power station energizes Rio Tinto’s port operations in Sept-Iles, Quebec.

    The decarbonization plans for the entirety of Saguenay-Lac-Saint-Jean operations go beyond hydroelectric power modernization. Two years ago, Rio Tinto announced a $1 billion investment to increase low-carbon aluminum production there with 96 new smelting cells, estimating that production would jump by close to 160,000 metric tons annually.

    Earlier this year, the company announced it was partnering with aluminum recycler Hydro on improving best practices to capture carbon for future use in aluminum electrolysis.

    Together, the two companies are expecting to invest close to $45 million over five years to decarbonize aluminum production and recycling.

    Most of the work will be focused on Rio Tinto’s facilities in Europe and Hydro’s in Norway. Both companies also will continue to work on decarbonization in their respective aluminum sectors independently.

     

    About the Author

    Rod Walton, EnergyTech Managing Editor | Managing Editor

    For EnergyTech editorial inquiries, please contact Managing Editor Rod Walton at [email protected].

    Rod Walton has spent 15 years covering the energy industry as a newspaper and trade journalist. He formerly was energy writer and business editor at the Tulsa World. Later, he spent six years covering the electricity power sector for Pennwell and Clarion Events. He joined Endeavor and EnergyTech in November 2021.

    Walton earned his Bachelors degree in journalism from the University of Oklahoma. His career stops include the Moore American, Bartlesville Examiner-Enterprise, Wagoner Tribune and Tulsa World. 

    EnergyTech is focused on the mission critical and large-scale energy users and their sustainability and resiliency goals. These include the commercial and industrial sectors, as well as the military, universities, data centers and microgrids. The C&I sectors together account for close to 30 percent of greenhouse gas emissions in the U.S.

    He was named Managing Editor for Microgrid Knowledge and EnergyTech starting July 1, 2023

    Many large-scale energy users such as Fortune 500 companies, and mission-critical users such as military bases, universities, healthcare facilities, public safety and data centers, shifting their energy priorities to reach net-zero carbon goals within the coming decades. These include plans for renewable energy power purchase agreements, but also on-site resiliency projects such as microgrids, combined heat and power, rooftop solar, energy storage, digitalization and building efficiency upgrades.

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