The Advantages of Hydropower

Hydropower is one of the best generating options. In fact, a complete life-cycle assessment shows that its greenhouse gas (GHG) emissions are very low.

For instance, a hydropower plant with a reservoir in a northern area emits 10 grams of carbon dioxide (CO₂) per kilowatthour produced, the same quantity as wind power. Solar power, generated via photovoltaic panels, emits four times more GHGs, and a coal-fired power plant produces 100 times more GHG emissions than a hydropower plant.

In fact, thanks to our use of hydropower, in 2009 the electricity sector accounted for only 0.6% of GHG emissions in Québec. A remarkable performance!

In Québec, transportation is responsible for 44% of GHG emissions. Eventually, electricity will be able to replace a significant portion of the petroleum products used as vehicle fuels on our roads. This electrification of ground transportation will have a major impact on Québec's environmental track record and on neighboring markets.

Thanks to its low GHG emissions, hydropower is an excellent way to fight climate change while supporting sustainable development.

   (in French only)

Greenhouse gas emissions and hydroelectric reservoirs

• Where do greenhouse gases come from?
• How do they affect the environment?
• Are reservoirs a source of greenhouse gas emissions?

Map - Electricity generation in Canada and the U.S. and its impact on greenhouse gases emissions

• Animated presentation [PDF]
• Presentation with comments [PDF]

• Map [PDF – 26.9 Mb]

Hydrological cycle –
La Grande complex

In 2004, 154 countries recognized hydropower as a renewable source of energy. Since the source of hydropower is water from annual precipitation over a vast area, it is considered inexhaustible.

In fact, water follows what is known as the hydrological cycle, described below.

The sun heats up the oceans, lakes and rivers, producing water evaporation. The resulting water vapor rises in the atmosphere where it condenses and produces clouds. When the weight of the water droplets or ice crystals which make up the clouds becomes too heavy, the droplets or crystals fall on the ground in the form of rain or snow. In this way, water returns to the earth and flows into lakes, rivers and oceans, and the cycle is repeated.

Hydrological cycle – Natural water cycle

Hydropower involves fewer energy losses during the generation process. In comparison, the transformation of fossil fuels, such as oil, natural gas and coal, usually leads to substantial losses in the form of heat. For example, when coal is burned to generate power, two-thirds of its energy is wasted. Water, on the other hand, is used to the last drop as it pushes against the blades of a power station turbine.

The world's saltwater and freshwater reserves

In fact, it's one of the most water-rich regions in the world. It boasts over 130,000 rivers and streams, and one million lakes. Over 40% of Canada's water resources are in Québec. Surface water reserves in the province (natural lakes and reservoirs) cover approximately 12% of its territory.