Energy and Water Power

n Potential energy is energy that is stored in an object. If you stretch a rubber band, you will give it potential energy. As the rubber band is released, potential energy is changed to motion. n Kinetic energy is energy of motion. A rubber band flying through the air has kinetic energy.

Potential Energy n A rock on top of a hill has a potential to do work. n The top of the hill is a high energy state and the bottom of the hill is a lower energy state.

Kinetic Energy n If the rock is allowed to roll down the hill, then the potential energy is converted into kinetic energy. n Kinetic energy is the energy that a moving object has.

Hydroelectric Power Using the power of water currents to generate electricity.

Hoover Dam

Grand Coulee Dam- Washington

Hydroelectric Power Niagara Falls n ml

Aswan Dam

Three Gorges Dam China

Three Gorges Dam China n Advantages –Inexpensive electricity –Control flooding that has devastated area n Disadvantages –Relocate 1.5 million people –Loss of ancient artifacts and archaeological sites –Endangering species n Dolphin, fish, birds –Loss of sediment=farmers need to use fertilizers

Benefits of the Three Gorges Dam n When complete, the dam will produce 85 billion kilowatt-hours of power each year. –clean power –equivalent to: n - 25 million tons of crude oil n - 50 million tons of coal n - 15 nuclear power plants n Help control flooding –In 1998, flood killed 4000 people, left 14 million people homeless, $24 billion of economic loss.

Consequences of the Three Gorges Dam n 1.5 million people need to be relocated n Reports of corruption, relocation money not getting to people but rather going to officials n 1300 archaeological sites (burial grounds, temples) will be lost n 1600 factories and mines will be submerged releasing toxins into water n Freshwater dolphin, Chinese river sturgeon, and other species pushed to extinction? n 265 billion tons of raw sewage dumped into river every year will now back up instead of going to ocean n 700 million tons of sediment is deposited by river every year, system to control this is untested, could cause collapse n 360 million people live in the Yangtze watershed, if 1/1000 chance of collapse occurs…