Renewable energy sources
Renewable energy is generated from natural resources such as sunlight, wind, water and
geothermal energy. These sources are considered renewable because they quickly replenish
themselves and are usually available in a never-ending supply.
Wind Energy
The wind can blow your hat off, rustle the trees, and even power your television. The wind has been
used by humans for hundreds of years, first to carry ships across oceans and later to pump water and
grind grain. Today, modern machines called wind turbines are used to make electricity. To produce a
lot of electricity, many wind turbines can be placed together on wind farms. Good sites for wind farms
are often found on windy hilltops, open plains, and shorelines.
Interesting facts:




Wind power has been the fastest-growing energy source in the world since 1990.
Denmark gets one–fifth of its energy from wind power, the highest percentage of any country
in the world.
The United States and China are the largest producers of wind power in the world.
In the United States, wind energy now produces enough electricity to power more than 9
million homes.
Water Energy
If you've ever stood in a fast–moving stream, under a waterfall, or on the ocean shore as waves come
crashing in, then you've felt the power of the water. The energy from moving water can be used to
create electricity in several different ways:



A hydroelectric dam captures energy from the movement of a river. Dam operators control the
flow of water and the amount of electricity produced. Dams create reservoirs behind them,
which can be used for recreation, wildlife sanctuaries, and sources of drinking water.
Wave power captures energy from waves on the surface of the ocean using a special buoy or
other floating device.
Tidal power captures the energy of flowing waters with the help of turbines as tides rush in
and out of coastal areas.
Interesting facts:


The world's great natural wonders has been generating electricity for more than 100 years?
Today, Niagara Falls is the biggest electricity producer in New York State, generating enough
electricity to light 24 million 100–watt bulbs at once!
Hydropower is the leading renewable energy source used to generate electricity in the United
States.

The first commercial U.S. power station using ocean waves to generate electricity is in the
works in Oregon. When finished, 10 “powerbuoys” in the ocean will generate enough
electricity to power 1,000 homes.