hydropower dams by: brittany marshall and maddy bergethon

Hydropower Dams

By: Brittany Marshall and Maddy Bergethon

Basics

• Relies on the water cycle• AC (alternating current) or DC (direct current)• AC is easier to use• Mechanical energy is harnessed from the

water and used to spin the turbines

History

Using water for energy= back to Romans and Egyptians= water wheelFirst water source to make electricity was in 18821903 began the rush of making them

Pros

• Very reliable power source• Generates a lot of power

Cons

Causes lots of floodingDisplaces wildlife= sufferingMigrating fish= dying

Weird Fact

• New Scientist claims that hydropower dams actually produce more greenhouse gasses than fossil fuel plants

• By deforestation

Turbine Types

• Impulse- – changes potential energy to kinetic energy– uses Newton’s 2nd law of motion– takes momentum of water and forces turbines to move– doesn’t have to be submerged or enclosed

Turbine Types

ReactionUse water pressure to spin turbineHas to be incased or completely under waterMost common typeUses Newton’s 3rd law of motion

Maintenance

• Designed to run for a long time• Little maintenance• Water erosion• Gets hit by rock/stick or other debris in water

Steps of Hydropower Dam

1. Dams holds water back in reservoir2. Gates open and gravity pulls water through

penstock and into powerhouse; pressure builds

3. Water hits large blades of turbine making them turn

4. Turbine blades turn together with series of magnets in generator

5. Magnets rotate past copper coils= AC current

Steps Continued

6. Transformer converts AC to higher voltage

7. Goes through power lines to customers

8. Used water is carried through overflow pipes and goes back to river; downstream

Hydropower in the US• Largest renewable

resource • 7% of our power• #2 producer with 306

billion kilowatts per hour(Canada = #1)• Generate enough to

support 28 million households

• = 50 million barrels of gas

Hydropower in the World

• 24% of the world electricity• 674,000 megawatts• Equivalent to 3.6 billion barrels of oil• Supply 1 billion people with power• 88% of the renewable energy sources• Norway= 99%!!!!!!!!!!!!!!! WOW!!!!!!!!!!!

Hydropower in the World

Top 31. Three Gorges Dam- China, construction started in

2008 and has not yet been finished when finished will generate around 22,500 megawatts.

2. Itaipu- Brazil & Paraguay, finished in 2003, generates around 14,000 megawatts

3. Guri- Venezuela, completed in 1986, generates around 10,200 megawatts

Citations

• http://drake.marin.k12.ca.us/stuwork/rockwater/Upload%20this%20doc--dams%20and%20hydropower%20report/history,%20water%20project.html

• http://www.waterencyclopedia.com/Ge-Hy/Hydroelectric-Power.html

• http://www.morriscanal.org/tech.htm

The End!!!