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Waterpower Facts

How Hydro Works

  1. In order to convert the potential energy of water to electricity, waterpower facilities use either a natural drop in elevation like at Niagara Falls, or create a drop using dams.
  2. The amount of electricity generated depends on the vertical distance the water falls and the volume of water.
  3. Water from the river or reservoir behind the dam, flows in through an opening called the intake.
  4. From the intake, water flows under pressure through a pipe called the penstock.
  5. At the end of the penstock a turbine is located. The force of the water turns the blades of the turbine which then turns the shaft inside the turbine.
  6. The shaft inside the turbine is connected to a generator, which generates electricity.
  7. Once the water passes the turbine it flows through a draft tube out of the station and back into the river.

Renewable Energy

Waterpower: Ontario’s primary source of renewable energy

Today, Ontario’s waterpower resources comprise about 25% of the province’s energy supply–with an installed capacity of 9,300 Megawatts. Nuclear power accounts for 51%,  natural gas for 10%, and other renewables (wind, solar etc.) for 13%.

An Energy-efficient Source of Electricity

  • The average facility converts energy to electric energy at a rate of between 75% and 95%.
  • A typical waterpower generating facility has a long life cycle of between 75 and 100 years.
  • The average energy payback ratio (energy required vs. energy produced) is by far the highest among all sources.
  • Relative to other sources, the production of waterpower could be considered a form of energy conservation.

A Province Rich in Water Resources

  • Ontario has more than 250,000 lakes and tens of thousands of kilometres of rivers and streams.
  • About 50 systems support all of Ontario’s waterpower production. Fewer than a dozen account for more than eighty percent.
  • Niagara Falls comprises almost a quarter of the installed capacity.
  • Waterpower facilities are located within 10 km of every major town and all cities in north-western Ontario.

Realizing the Potential for Clean, Renewable Waterpower

  • An inventory of waterpower potential in Ontario identified 2,000 sites with basic hydraulic conditions (regularly flowing water and change in elevation) to produce waterpower energy.
  • Just 200 sites have been developed in the last century.
  • Distance to the transmission grid, other natural resource values, and the demand for renewable energy are important factors in realizing waterpower potential.

Sustainable Energy: an Asset for the Future

  • Like other natural resources, Ontario’s waterpower resources must be managed and developed to meet present needs and anticipate the requirements of future generations.
  • The waterpower potential that remains in Ontario should be treated as an asset that can continue to contribute energy, now and in the future.
  • Acknowledging and protecting this potential will increase our energy options for the future