How hydropower works
Hydropower has been propelling humanity forward for thousands of years.
Over 2,000 years ago, the Greeks used flowing water from rivers to turn paddle wheels, the motion spinning cranks on grain mills, grinding wheat into flour. The evolution of the modern hydropower turbine began in the mid-1700s and helped launch the Industrial Revolution. Today, some of North America’s largest hydropower plants have been in operation for more than half a century.
The power of water in action
A common type of hydroelectric plant, known as an impoundment facility, uses a large concrete or stone dam to corral river water in a reservoir. The reservoir can act as a large battery, supplying water to the generating station where there is demand for electricity. Other types of hydroelectric plants, called run-of-river facilities, use the natural flow of the river to generate power. These types of facilities generally don’t store water to produce power. With either method, the process of generating electricity is the same:
Water is released through channels called penstocks in the dam wall or at the end of a canal for run-of-river facilities.
The water flows through turbines, spinning their propeller-like blades and the metal shafts to which they’re attached.
The spinning metal shafts connect to an electric generator. There, a rotor of electromagnets circulates around a coil of copper wires to produce electricity.
Power is carried through transmission lines connected to the generators, ultimately bringing it onto one of several regional grids, where it merges with electricity generated from other sources.
Green, cost-effective and available whenever it's needed, hydropower is a critical resource in our energy future.
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Hydro-Québec has been a longstanding reliable partner for decades in the Northeast.
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