Let's Explore Renewable Energy!
For thousands of years people have harnessed the wind's energy. People used the wind to sail their ships on the rivers and oceans. Later windmill's were built and used to grind wheat, corn, and other grains and later to pump water from wells and to cut wood in sawmills. Today we use wind energy to generate electricity.
Wind is a renewable fuel because it uses the heat of the sun (solar energy) so there is no fossil fuel needed to make wind.
Where does wind come from?
Wind is caused by the uneven heating of the earth's surface by the sun. During the day the air above the land heats up faster than the air above water like oceans and lakes. The air above the water is cooler and heavier. The uneven heating of the air is because the earth is made up of different surfaces and elevations, like the oceans, lakes and rivers, forests and jungles, deserts and mountains. The warm air over the land expands and rises and the cooler air over the water rushes in to take the place of the warmer air creating winds.