Explain the differences between the use of hydroelectric energy and coal.

Answer:

Hydroelectric energy uses flowing or falling water to turn turbines, whereas coal is mined and burned to produce heat and electricity. Hydroelectricity is renewable and produces little direct air pollution, but dams can block fish movement, change river flow, and trap sediment. Coal is nonrenewable and burning it releases carbon dioxide and other air pollutants; mining and coal waste can also damage land and water.