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Kids&Science Energy Waterpower How Do You Generate Electricity From Water?
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See also: A Manucritical Hydro-Electrical Power Plant, Burning Ice 

 

How Do You Generate Electricity From Water?

You walk alongside a river, and suddenly the water does not flow anymore. It is dammed up before a water power plant. But how is the electricity generated from the water, now?

The Hydroelectrical Power Plant

Water power plants transform the potential energy of the piled up water into the kinetic energy of turbines by means of runners. These turbines then drive generators, which generate electricity. The greater the difference in altitude and the greater the available torrents of water, the higher the amount of generated electricity.

Nature puts great heights of fall at our disposal in the mountains, and great torrents of water in rivers and streams. Thus, the ground determines the type of construction of the power plant. By the rivers, river power plants for great masses of water with little height of fall are built, whereas reservoir power stations for small torrents of water and a great height of fall are built in the mountains.

By the sea, the difference in altitude between low tide and high tide is exploited in tidal power stations.

How much energy does the biggest power plant on earth supply?

The biggest power plant on earth was built in Itaipú in Brazil. Its 18 turbines generate 12.6 million kilowatts of electricity. In comparison, an Austrian uses 6470 KWh of electricity per year.

 

 

 

The dam of such a power station is 196 m high and 1200 m long. The reservoir is 170 km long and has an average width of 7 km.

The Itaipú power station will soon be replaced by the Three Gorges Dam in China. For this project, about one million people have to be moved, since the length of the reservoir will be more than 600 km. As of 2009, 26 generators will be generating electricity day and night.

A runner for this power station weighs 416 tons, which is equivalent 381 VW-Golfs! This power plant will supply one million people with electricity. In comparison to energy generation from coal, this hydroelectrical power plant will spare the environment 100 million tons of CO2 and 2 million tons of SO2.

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