Hydroelectric Power

How it Works

• Hydroelectric power mostly comes from dams on large rivers with drops in elevation.

• Water is stored in the reservoir behind the dam. At the bottom of the dam wall there is the water intake, which is caused by gravity.

• The water then falls through the penstock, which moves a turbine propeller. Then the turbine shaft goes upward into the generator, and the power is produced.

• Connected to the generator are power lines that carry the electricity to mines and homes.

• Then the water goes past the propeller into the river and out of the dam.

How the Generator Works• The generator converts mechanical energy into

electricty• Electromagnets are made from direct current that

comes from wire looped around magnetic steel laminations called field poles which are mounted on the outside off the rotor

• Attached to the rotor is the turbine shaft which rotates at a set speed

• When the rotor turns, electromagnets move past the conductors in the stator, this causes electricity to flow

Pumped Storage• The demand for electricity power isn’t constant, during the day it’s

much higher.• Using the pumped storage method, water is stored for times of high

demand. • Water that has already been pumped is put in a storage pool above the

power plant during times of low demand. • When the demand is high, the water flows back through the turbine

generators and energy is produced.

Works Cited• "Hydroelectric Power: How it Works." USGS. N.p., 8 Feb. 2011. Web. 17 May 2011.

<http://ga.water.usgs.gov/edu/hyhowworks.html>. • "Hydroelectric Power." TVA Kids. N.p., n.d. Web. 20 May 2011.

<http://www.tvakids.com/electricity/hydro.htm>. • "Hydroelectric power and water use." USGS.gov. N.p., 8 Feb. 2011. Web. 20 May

2011. <http://ga.water.usgs.gov/edu/wuhy.html>. • "Hydroelectric Power." TVA.gov. N.p., n.d. Web. 20 May 2011.

<http://www.tva.gov/power/hydro.htm>.