Generating Electricity: Hydroelectric Power

In Canada, we often use moving water to generate electricity. This is called hydroelectric power. For short, we call it hydropower. Hydropower produces almost two-thirds of electricity in Canada.

Did you know?

Hydroelectricity generates 16% of all the electricity in the world.

A hydroelectric system has pipes, a turbine, and a generator. The pipes are called the penstock. They direct the water. A hydroelectric system may also include a dam. Is there a dam near where you live?

Potential energy is stored energy. Kinetic energy is the energy of motion. Water in the reservoir has potential energy. When that water moves down into the turbine, it becomes kinetic energy. The moving water spins the turbine. This converts kinetic energy into mechanical energy. The turbine is attached to a rotor in the generator.

How much energy does a hydroelectric system produce? Mostly, it depends on two things:

1. the pressure of the water hitting the turbine 
2. the volume of water passing by the turbine

Sometimes, dams are located above generators. These dams increase the pressure and control the volume of water. They help the hydroelectric station generate more electricity.
 
Hydroelectricity is a renewable resource. We can use the water over and over again to produce electricity. But there are some downsides to hydroelectricity, too. 

Hydroelectric systems divert natural water systems. This impacts water flow and can change the ecosystem. These changes can affect the plants and animals that live there. 

Some hydroelectric systems use dams. The reservoir behind a dam can be very useful. During dry periods, people can use this water for drinking water. They can also use this water for irrigation. They can even use this water for recreation.

But a dam can cause some problems, too. Dams can flood land. If land is flooded, people cannot farm or hunt on it. Flooding can also damage the ecosystem. For example, animals nearby might lose their habitat. The type of aquatic life in the area can change, too. 

When there is a flood, plants can decay under the water. This produces a greenhouse gas called methane. 

Finally, sometimes dams fail. This can cause a lot of damage to human and natural environments nearby.

There are many benefits to hydropower. But it is also important to weigh the risks!