|
 |
|
|
Making electricity with water
Hydroelectric power is a timeless, renewable resource that fuelled Ontario's economic growth in the first half of the twentieth century. Today it accounts for about one quarter of Ontario Power Generation's electricity production. Hydroelectric generation, or electricity made with water, is our lowest-cost power source. We made approximately 35.7 terawatt-hours of electricity with water in 2005.
|
|
|
Stewartville Hydroelectric Station |
How hydroelectric generation works
1. Forebay
2. Intake
3. Transformer
4. Generator
5. Penstock
6. Turbine
7. Draft tube
8. Tailrace
See how it works.
|
|
|
In very simple terms, electricity is produced by spinning electromagnets inside a coil of wire in a generator to create a flow of electrons. To keep the electromagnets spinning, a hydroelectric station uses falling water.
Water + gravity = electricity
Most hydroelectric stations use either the natural "drop" of the river or build a dam across the river to raise the water level and provide the drop needed to create a driving force. Water at the higher level (the forebay) goes through the intake into a pipe, called a penstock, which carries it down to the turbine. It's like a waterfall inside a pipe. |
|
|
The turning turbine
The turbine is connected to a generator. When the turbine is set in motion, it causes the generator to rotate, and electricity is produced. The falling water, having served its purpose, leaves the generating station and joins the river again. |
|
|
An important electricity source
The historic importance and future potential of hydroelectric power is because of its low production costs, reliability, flexibility and its reliance on water - a renewable resource that is plentiful in Ontario.
Our numbers
OPG operates 36 hydroelectric stations, 29 small hydroelectric plants that are considered to be “Green Power” under the federal government's “Ecologo” program, and 240 dams on 26 river systems. The smallest station has a generating capacity of just one megawatt (MW); the largest more than 1,300 MW.
|
|
|
