IV. Hydroelectric Power

A. Definition

1. Uses kinetic energy of water to turn turbines and generate electricity

2. two modern methods in use:

a. Damming a river behind a concrete wall forming a reservoir

1. a single channel controls flow

2. Has turbine in channel

3. Called the storage method

b. Run of the River technique allows more natural flow

1. A portion of the river is diverted to a powerhouse

2. water rejoins the river downstream

3. Makes 16% of the worlds electricity

a. In Sweden accounts for 50%

B. Impacts

1. Positives

a. Clean- hydroelectric power produces little to no pollution

b. As long as water cycle happens it will continue

c. Efficient- energy gained to used is 10:1

2. Negatives

a. Destroys habitats- upstream floods downstream drains

1. run of river decreases flow and volume

b. Prevents nutrients from reaching downstream areas

c. Disrupts flood cycle

d. Changes temperature of water

e. Disrupts migration cycles

C. Future

1. Three Gorges Dam in China is most recent large project

a. Finished in 2009 immediately put China at top producers of hydroelectricity2. Not likely to expand more

a. 98% of useable rivers in US are usedb. other 2 % protected

3. Pressure from citizenry has actually caused some to be dismantled