Hydroelectric power

Hydroelectricity is a renewable and effective type of energy, which generates electricity from water using kinetic energy. Although there are many controversial opinions on using hydroelectric power due to the effects on the wildlife, biodiversity and population of the nearby territories, hydropower plants produce the largest amount of renewable energy on the planet without environment pollution and greenhouse gas emissions.

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Humans have been harnessing the power of water for centuries. The records prove water mills being used in different parts of the world back in the 3rd century BC. After engineer James Francis introduced the first water turbine, hydropower became an electricity source in the 19th century and the first hydroelectric power plant started its operation in Wisconsin in 1882. Today, hydropower provides about 20% of the world’s electricity and generates 74% of the planet’s renewable energy. China is the largest producer of hydropower, followed by the United States, Brazil, Canada, India, New Zealand and Russia. The world’s biggest hydroelectric plant is Three Gorges on Yangtze River in China. The gigantic dam is 1.4 miles (2.3 kilometers) wide and 607 feet (185 meters) high. The plant generating most of the electricity is Itaipu located on the Parana River between Brazil and Paraguay. 


What is hydroelectric power and how is it generated?

Hydroelectric power or hydroelectricity is the process by which we generate electricity from water using the kinetic energy. Hydroelectricity is a renewable type of energy using naturally replenishing resources such as water and wind. Water is moving downward turning a turbine, which is connected by a metal shaft to an electric generator. The metal shaft movement powers a motor to produce electricity. The amount of electricity depends on the amount of water moving through the system and how far it falls. At the final stage, the electricity is sent through cables and transferred to homes, businesses, and factories. This is how the typical hydroelectric plant functions. 


Types of electricity hydropower plants:

Dam is the most common type of hydroelectric power using a concrete dam to create a reservoir. Water is blocked in a dam and released flowing downwards spinning the turbine blades to produce a specific amount of electricity

Pumped storage is a method when the water is pumped from a dam at a low level up to a dam at a higher level. The pumps are powered with cheap electricity and release it when the demand is rising. 

Run-of-the-river is a type, which uses natural water flow instead of a dam but works with a similar mechanism as a dam hydropower plant. This type of hydropower facility is not so popular as the water amount cannot be controlled. 

Tidal power is a hydropower plant type working with the tidal movements and generating energy twice a day. 


The main advantages of hydroelectricity:

  • renewable energy source using water without quantity reduction,

  • creates no greenhouse gas emissions during its service,

  • does not require additional costs after the facility is built,

  • reliable source constantly producing energy,

  • create employment opportunities in rural areas,

  • long-lasting operational period.


Despite being an effective and renewable energy source, there are certain disadvantages and negative tendencies about using the hydroelectric power:

  • effect on nearby territories, possibility of covering agricultural lands, homes, risks of the floods and draughts,

  • damage or modifications of the the fish habitat, loss of freshwater biodiversity,

  • dependence on the hydrology and precipitations, 

  • high costs of hydroelectric facility building.

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