hydroelectric power

Hydroelectric Power

Hydroelectric power is a kind of energy source which generates electricity due to the immense force of falling water. A well built and huge hydroelectric power station can produce electricity for the whole country. For example "The Gorges Dam in China. China is now the largest hydroelectricity producer which gives seven hundred, twenty one terawatt-hour. This has been stated in 2010. Whereas Bhankra Nagal Dam is known as the world's highest straight gravity dam. Approximately 20% of global electricity is created by number of hydroelectric power stations.

Dams are made up to trap water. A dam is always broader at the bottom compared to the top as the force of water increases by the intensity.
How hydroelectric power works:First the water enters a tube named "penstock", from the penstock the pressure of the water goes through a turbine. The immense force of water creates a spark(electrons) further the electrons are caught by the generator, then it moves onto the transformer.The transformer passes the energy which are the electrons to electric cables. Hence electricity is created.

Advantages:

• No kind of pollution id produced, like water, air pollution.
• No waste is produced.
• Electricity can be produced constantly.
• It is said that hydroelectric power is more reliable than wind or solar power as water can be stored and it can be reused the next time.
• Hydroelectric power reduces the green house emissions.
• Hydroelectric power doesn't pollute air whereas some power plants burn coal which is a fossil fuel and natural gases.
• The flow of water can be controlled via turbine to generate electricity, depending on the situation. 

Disadvantages: 

• Dams are very costly and they should be constructed at a high standard.
• Flooding areas cause deforestation and ruin animal lifestyle.
• Citizens of a certain place might have to move out because the particular land is needed for building a dam.
• Power plants can be affected by drought (dryness), which will lead to lack of water or at times water wouldn't be available. Therefore no electricity would be produced.
• Dams have a huge draw back when it comes to 'ecosystem of a river.' Many fish die and can't migrate due to the dam's construction. There is loss of fish species.
• Dams have less availability as they can be built in only few rivers.