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water power

From waves to waterfalls, water is usually on the move. And that means it has energy. When this energy is captured and turned into electricity, it is called water power or hydropower. Hydroelectric plants use the energy of flowing water to turn turbines and generate electricity. Today, most hydropower is produced near rivers or dams. Some also comes from the power of waves, tides, and currents.

Stats

Definition: the process of producing electricity using the power of flowing water
Carbon Dioxide Emissions: Almost none!
Cost: cheap (compared to other energy sources)
Location: near rivers and dams
Current Use: almost 15% of the world's energy
Cool Fact: The world's first hydroelectric plant opened in 1882, in Wisconsin.

Stumper

Most people who benefit from water power live near:

the ocean

large lakes

rivers

Correct!

Most hydroelectric plants are built along rivers, where they capture the energy of water flowing downstream.

Stumper

Hydroelectric plants have been producing electricity for decades. Today, they provide about ______ percent of the world's electricity:

Correct!

Water power is the biggest source of electricity after coal and natural gas. But big hydropower plants must be built along rivers and require dams. Solar power is growing much faster than water power.

Fact or Fiction

Hydroelectric plants can have a negative impact on communities and the environment.

Fact

Fiction

Fact

People and animals are sometimes displaced to build dams for hydroelectric plants. Dams can also disturb river ecosystems and the routes of animals like migrating fish.

Fact or Fiction

There is an unlimited supply of water power on Earth.

Fact

Fiction

Fact

Water power is a renewable resource. The Sun's energy constantly moves water around Earth in the form of clouds, rain, rivers, and ocean currents. That means the ultimate source of water power will never run out.

Image credits: main image, courtesy of Ocean Power Delivery.

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