Hydroelectric in Canada — Inside the World’s Second-Largest Producer

Canada is one of the great hydroelectric nations of the world — the second-largest producer of hydel (hydroelectric) electricity on earth, behind only China. Around 60% of all electricity generated in Canada comes from hydroelectric, a proportion few large industrialised nations come close to matching. Yet Canada’s hydel story is fundamentally different from that of the emerging hydroelectric nations of South Asia or Africa. Where those countries are racing to develop untapped potential, Canada has already built an enormous, mature hydroelectric system over more than a century — and now faces a different set of questions:

how to modernise ageing assets, how to manage the commercial legacies of decades-old contracts, and how to keep expanding in an era where the age of the mega-dam may be drawing to a close. This guide looks inside the engineering, the scale and the evolving future of hydroelectric in Canada.

The Scale of Canadian Hydroelectric

Canada holds roughly 82,000 MW of installed hydel (hydroelectric) capacity, placing it fourth in the world for total installed capacity behind China, Brazil and the United States, while ranking second globally in actual hydroelectric generation. Hydroelectric supplies approximately 60% of Canada’s total electricity — and in several provinces the dependence is far higher. The country is home to more than 15,000 dams, of which over 1,150 are classified as large dams, spread across a vast landscape of powerful rivers descending from mountain ranges, northern watersheds and the Canadian Shield.

The geographic concentration of this capacity is striking. The province of Quebec alone holds over 41,000 MW of installed hydel capacity — more than most entire countries — and generates around 94% of its electricity from hydroelectric. British Columbia, Manitoba, Newfoundland and Labrador, and Ontario all have substantial hydel systems.

This provincial concentration reflects Canada’s geography: the greatest hydroelectric resources lie where powerful rivers, high flows and suitable terrain coincide, and Canada’s federal structure means each province has developed its own hydroelectric system, often through large provincial Crown corporations such as Hydro-Québec, BC Hydro and Manitoba Hydro.

What sets Canada apart from emerging hydel nations is maturity. Much of this capacity was built between the 1950s and 1990s in an era of ambitious mega-project construction. The result is a hydroelectric system that is not only enormous but decades old — reliable, fully integrated into national and cross-border grids, and now entering a phase where modernisation and refurbishment are as important as new construction.

The Great Plants — Engineering on a Continental Scale

Canada’s hydel (hydroelectric) system is anchored by some of the largest and most impressive generating stations in North America — feats of engineering built to harness the enormous rivers of the Canadian north.

Robert-Bourassa — Canada’s Largest

The Robert-Bourassa generating station in Quebec’s James Bay region is Canada’s largest hydel power plant, with an installed capacity of 5,616 MW. Part of the vast La Grande hydroelectric complex, it is fed by an enormous northern watershed and features an underground powerhouse carved deep into the Canadian Shield.

The facility completed a major rehabilitation programme in 2022 — a clear illustration of the modernisation now central to Canadian hydropower, where plants built decades ago are being systematically upgraded to extend their operational lives and improve their output. The broader James Bay development includes multiple large stations such as La Grande-3 and La Grande-4, together forming one of the largest hydropower complexes on the continent.

Churchill Falls — The Underground Giant

The Churchill Falls generating station in Labrador is one of the largest underground hydroelectric stations in the world, with an installed capacity of 5,428 MW generated by eleven underground turbines. Commissioned in 1971, it remains a landmark of hydel engineering — built in a remote, harsh environment through an immense construction effort. Churchill Falls carries a particularly instructive commercial history.

Under a long-term power purchase agreement signed in 1969, nearly all of its output was committed to be sold at a fixed price for decades — an arrangement that, as electricity prices rose over the following half-century, became one of the most-studied examples in the world of the risks of very long-term fixed-price power contracts.

As the original contract approaches its expiry, the parties have moved to renegotiate the terms and to study new development on the same river system — a reminder that the commercial structure of a hydel project can matter as much over its lifetime as the engineering itself.

Site C — One of the Last Great Mega-Dams

The Site C project on the Peace River in British Columbia — since named the John Horgan Dam and Generating Station — reached full commissioning in 2025, following phased commissioning of its generating units beginning in 2024. With an installed capacity of around 1,100 MW, it adds approximately 5,100 GWh of electricity annually to British Columbia’s grid — enough to power the equivalent of hundreds of thousands of homes.

Site C is significant not only for its scale but for what it represents: one of the last great conventional mega-dams likely to be built in Canada for the foreseeable future. Its lengthy, complex and at times contentious development reflects the reality that in a mature hydropower nation, building new large dams has become increasingly difficult — environmentally, socially and economically — pushing the future of Canadian hydel toward modernisation, smaller projects and storage rather than ever-larger dams.

Modernisation — The Real Frontier of Canadian Hydroelectric

In an emerging hydel (hydroelectric) nation, the central challenge is building new capacity. In a mature nation like Canada, the central challenge is different — keeping an enormous fleet of ageing assets running efficiently for another half-century. This is the real frontier of Canadian hydropower today, and it holds important lessons for every country whose hydel infrastructure is entering middle age.

Many of Canada’s largest generating stations were commissioned decades ago, and their turbines, generators, transformers and control systems are reaching the point where refurbishment delivers more value than new construction. Refurbishing an existing hydel plant is one of the most attractive investments in the entire energy sector — the dam, reservoir, waterways and transmission connections already exist, so upgrading the electromechanical equipment can increase capacity and efficiency at a fraction of the cost of a greenfield project, with minimal additional environmental impact.

The completion of the Robert-Bourassa rehabilitation in 2022 is a flagship example, but modernisation is happening across the country, from major generating stations to smaller heritage plants.

This modernisation frontier demonstrates a principle that applies globally: hydel infrastructure is not a one-time build but a long-term asset requiring periodic reinvestment. A generating station commissioned in the 1970s can, with well-planned refurbishment, continue delivering clean electricity into the second half of the twenty-first century.

The engineering discipline required to refurbish a live, ageing plant — often while keeping as much of it in service as possible — is a distinct specialism, different from new-build commissioning, and one that mature hydropower nations must master. As the world’s hydel fleet ages, the modernisation expertise that Canada and other established hydropower nations are developing will become increasingly valuable everywhere.

Exports, Grids and the Weather Question

Canada’s hydel (hydropower) system is deeply integrated with the electricity markets of the United States. Provinces with large hydropower surpluses — particularly Quebec, Manitoba and British Columbia — export significant quantities of clean electricity southward across the border, making Canadian hydropower a major supplier of low-carbon energy to the northeastern and northwestern United States.

This export role gives Canadian hydel both commercial value and strategic importance in North American decarbonisation, as US states seeking clean electricity increasingly look to Canadian hydropower to help meet their targets. The flexibility of large hydropower reservoirs also allows Canada to act as a balancing resource for the growing wind and solar capacity on both sides of the border — storing energy when variable renewables are abundant and generating when they are not.

Yet Canada’s heavy dependence on hydropower also exposes a genuine vulnerability — weather. Hydropower generation depends on water availability, and water availability depends on precipitation and snowpack, which vary year to year and are increasingly affected by a changing climate.

In 2023, Canadian hydropower generation fell by around 37 terawatt-hours — a drop of roughly 9% year-on-year — driven by drought conditions and record temperatures. For a country that relies on hydel for 60% of its electricity, a significant reduction in water availability is not a minor fluctuation but a national energy concern.

This weather sensitivity is one of the strongest arguments for a diversified generation mix and for investment in storage — and it is a challenge that every hydropower-dependent nation, from Canada to Norway to Nepal, increasingly shares as climate variability grows.

The Future of Canadian Hydroelectric — Beyond the Mega-Dam

The future of hydel (hydropower) in Canada will look different from its past. The era of building enormous new conventional dams is drawing to a close — Site C may prove to be one of the last of its kind — but this does not mean the end of hydropower growth. Instead, Canadian hydel is evolving along several new directions at once.

Refurbishment and modernisation of the existing fleet will remain the largest single source of value, extending the lives and improving the output of assets built generations ago. Pumped storage hydropower is moving up the agenda as the ideal partner for expanding wind and solar generation — with major pumped storage projects under development, including what would become some of Canada’s largest storage facilities, designed to store surplus renewable energy and release it when needed.

Northern and remote community projects, often developed in partnership with Indigenous communities, are replacing diesel generation with clean run-of-river hydel in places far from the main grid — smaller in scale but transformative in local impact.

And selective new development continues where it makes sense, including potential new capacity on river systems that already host major hydropower infrastructure.

Recent policy signals reinforce this direction. New legislation aimed at accelerating hydropower development was enacted in 2026, and major provinces have announced intentions to pursue significant new hydel and storage capacity as part of their long-term decarbonisation and electrification plans.

As Canada moves to electrify transport, heating and industry, demand for clean electricity is set to rise substantially — and hydropower, with its unmatched combination of scale, reliability, flexibility and low operating cost, will remain the backbone of the Canadian electricity system for decades to come.

Field Engineer’s Perspective — What Canada Teaches

Canada offers a preview of where every major hydel (hydropower) nation eventually arrives. The emerging hydropower countries of South Asia, Africa and Southeast Asia are today where Canada was decades ago — racing to convert untapped potential into installed capacity.

Canada shows what comes next: a vast, mature fleet whose central challenges shift from construction to modernisation, from building dams to refurbishing turbines, from developing rivers to managing the commercial and environmental legacies of what was already built.

Several lessons stand out for engineers anywhere in the hydropower sector. First, the commercial structure of a hydel project matters over its entire lifetime — the Churchill Falls contract demonstrates that a decision made at financial close can shape a project’s economics for half a century or more.

Second, refurbishment is engineering of the highest value — extending the life of existing assets delivers clean capacity at a fraction of the cost and impact of new construction, and the specialist discipline of modernising ageing plants deserves as much respect as new-build commissioning.

Third, even the most hydropower-rich nation on earth is not immune to the weather — Canada’s drought-driven generation drop is a reminder that hydrology governs hydropower everywhere, and that diversification and storage are essential companions to hydel dependence.

For a hydropower engineer, Canada is a case study in what a century of hydel development ultimately produces — not just megawatts, but a mature system requiring a different kind of expertise to sustain.

The countries building their hydropower systems today would do well to study how the established nations manage theirs, because the modernisation challenges Canada faces now are the challenges every hydropower nation will eventually inherit.

Conclusion

Hydroelectric in Canada is a story of continental-scale engineering, deep national dependence and quiet evolution. As the world’s second-largest hydel (hydropower) producer, generating around 60% of its electricity from water, Canada has built one of the most impressive hydropower systems on earth — anchored by giants like Robert-Bourassa, Churchill Falls and the newly completed Site C.

Its future lies not in ever-larger dams but in modernising what exists, adding pumped storage to balance renewables, extending clean power to remote communities, and sustaining a mature fleet for generations to come. For engineers, developers and policymakers across the global hydel sector, Canada is both an inspiration and a preview — a nation that shows both the extraordinary value of hydropower and the long-term stewardship it demands.

For more on the global hydel sector explore our complete guides on Hydel Power in Nepal, Solar and Hydropower Integration and Grand Inga Hydropower Project.AIS vs GIS Switchyard in Hydropower Plants — A Field Engineer’s GuideWhat “Water to Wire” Actually Includes — And What It Doesn’t