Hydroelectric+Energy

=On this page you will find:=
 * Definition/Classification
 * Chart/Graph
 * Video
 * Picture
 * Survey
 * Summary
 * Works Cited (Bibliography)

Group Members: Nevin Manu (Picture and Summary), Kailey Fox (Video and Chart), and Tori Salazar (Definition, Survey, and Works Cited)

=**Definition**=


 * Hydroelectricity is the term referring to electricity generated by hydro power**.

=**Chart**=


 * ** Advantages of Hydroelectric Energy ** || ** Disadvantages of Hydroelectric Energy ** ||
 * ** Hydroelectric power produces no pollution ** || ** Damming rivers causes changes in ecological cycles and surrounding landscapes; self-regulating ecosystems are changed into ones that must be managed. ** ||
 * ** Plants usually have an expected life span two to three times longer than conventional thermal power plants. ** || ** Dams are vulnerable to natural forces. There is a high direct death rate from the failure of dams ** ||
 * ** Hydroelectric power plants require little maintenance. ** || ** River channels downstream from dams are more vulnerable to erosion. ** ||
 * ** Hydroelectric power is one of the most responsive (easy to start and stop) of any electric power generating source. ** || ** Construction costs of large-scale hydroelectric ** ||

=**Video**=

media type="custom" key="8852412"**This video explains how dams convert energy from water to make electricity. It describes how a dam is really an enormous concrete wall that is built on a river. If the river is flowing to the right, the wall holds the river back so the water forms a large deep lake behind it. Inside the dams, are some long tubes. River water falls down the tubes to the turbine, which are specially made fans. The water is heavy, and when it falls the energy from its movement makes the turbine spin with very great force. The turbines are part of the generators that take the kinetic energy from the spinning turbines and turn it into electrical energy. The electricity goes along the power lines so that other cities can use it.**

=**Picture**=


 * [[image:AP091014044944.jpg width="356" height="217"]] || ==Water flows through the gates of the Lake Fork dam near Quitman,Texas as a duck hunts for fish in the spillway on Wednesday,October 14, 2009. Recently, heavy rains have raised the water level of the lake, and has caused local flooding of roads and forcing the closure or delayed opening of many schools in east Texas.== ||

=**Survey**= media type="custom" key="8866826"

=Summary=

===Water is a valuable source of energy. Unlike non-renewable resources that cause pollution, water is a renewable resource that doesn`t cause pollution. The first-water powered plant built to generate electricity was built in Appleton, Wisconsin, in 1882.This hydroelectric plant made water power a major source of electric power. Now hydroelectric is being used around the world. Today, nearly all the water power is used to generate electricity. Many hydroelectric dams have been combined with thermal plants so that when the hydroelectric dam cant produce the power, the thermal plant will. Hydroelectric dams are very useful for generating electricity when they are in great demand, because then they can be turned on and off rapidly. The potential water power of the world is about 2 1/4 billion kilowatts of electric power. This is a very close estimate, because the flow of many large rivers have not been measured yet. Of this potential, about 600 million kilowatts are produced. And out of all these country`s, the United States has about sixth of the worlds devoleped power.===



A hydroelectric power plant uses the force of falling water from a reservoir to turn a turbine that drives a generator. An exciter powers the rotor. As the rotor and its magnetic field turn, an electric charge is created in the stator. A transformer increases the voltage of the current coming from the stator.

Hydroelectric power plants called //pumped-storage hydroelectric plants// can store energy by operating in reverse. When the demand for electric power is low, such plants can use their generators as motors to turn the turbines. The turbines then function as pumps, raising water to the reservoir. The water can be used at a later time to produce electric power. Hydroelectric power plants cost less to operate than fossil-fueled plants and do not pollute the air. The number of hydroelectric power plants is limited, however, by the availability of water power and suitable locations for dams and reservoirs.
 * Hydroelectric power plants** generate about 16 percent of the world's electric power and about 7 percent of the electric power produced in the United States. Such plants convert the energy of falling water into electric energy. A hydroelectric plant uses water that is stored in a reservoir behind a dam. The water flows through a tunnel or pipe to the plant's //water turbine,// or //hydraulic turbine.//As the water rushes through the turbine, it spins the turbine shaft, which drives the electric generator.

=**Works Cited**=
 * Energy Kids ([])
 * Energy Resources ([])
 * World Book ([])
 * Britannica Online ([])
 * Teacher Tube ([])