HYDROELECTRIC+POWER+-+William

=HYDROELECTRIC POWER=

HOW DOES IT WORK

Large quantities of water are stored at the top of a dam, this is called the reservoir. When electricity is needed the water is released and flows down through a large tube into a turbine. The water pushes the turbine causes it to spin this causes a generator to work. This generator produces then produces electricity which is then supplied to places where it is needed. The water used to spin the generator is expelled back into a river.

AN EXAMPLE IN THE WORLD

Hoover Dam: Hoover Dam was constructed in 1936 and is situated between the borders of US states Arizona and Nevada on the river Colorado. The Dam itself is place in between the two large canyon walls of the Black Canyon. It was constructed for a flood control mechanism, Hydroelectric power station and to provide a source of irrigation water. The company that built the dam was Six companies.Inc and as the dam was so large many construction methods were untested and over 100 workers lost their lives.

ENERGY CHANGES Gravitational Potential energy --> Kinetic --> Electrical --> Heat --> Sound Blue indicates that it is useful energy, whilst red indicates that it is not useful energy.

FIGURES The top three Hydroelectric power users are China, canada and Brazil clocking in at 585.2, 369.5 and 363.8 Terawatts an hour (TWh) respectively. Brazil, Canada, Norway,Paraguay, Switzerland and Venezuela all produce more electricity from hydroelectricity than any other energy source. Paraguay produces all of its electricity from hydroelectric power.

ENVIRONMENT: Since no fossil fuels are burnt in the process no CO2 is produced. However in the construction of the dam vast amounts of fossil fuels are used. Since a large amount of space is used for the placement of the reservoir many ecosystems are destroyed and large vast amounts of lands used for agriculture and such are flooded. Due to climate change river flows can either speed up or slow down. If the flow is too fast then the dam can be simply adjusted and allows it produce more energy. If the dam slows down it can cause severe power shortages in countries where it is heavily depended on. Finally, due to the flooding many of the flora and fauna may decay in an anaerobic environment and cause large amounts of methane to be produced which is another green house gas. This only applies to areas with tropical or temperate climates.