Presentation on theme: "Wind is moving air. We can use the energy in wind to do work. Wind Energy."— Presentation transcript:
Wind is moving air. We can use the energy in wind to do work. Wind Energy
Early Egyptians used the wind to sail ships on the Nile River. People still use wind to move them in sail boats. In Holland, people used windmills to grind wheat. The Pilgrims used windmills to grind corn, to pump water, and to run sawmills.
How Wind Is Made The energy in wind comes from the sun.
When the sun shines, it heats the earth. The air over the land gets hotter than the air over the water. The hot air rises and cooler air rushes in to take its place. The moving air is wind. How Wind Is Made
Windmills catch the wind. When the wind blows it pushes against the blades of the windmills. The blades spin around. They turn a generator to make electricity.
Wind Farm Sometimes there are hundreds of windmills in one place. This is called a wind farm. Some are as tall as 20- story buildings! Today we use big windmills to catch the wind.
Wind Farms One windmill alone doesn’t make much electricity. Most wind farms have many, many windmills. Wind farms take up a lot of land, but most of the land they are on can still be farmed or used to graze animals.
Today wind energy makes only a little of the electricity we use. Wind Energy Today Wind energy only produces enough electricity to serve one million households. That’s enough to power a city the size of Chicago, Illinois.
Wind Energy is Renewable As long as the sun shines, there will be winds on the earth. We will never run out of wind energy. It is also free, since no one can own the sun or the air!
Wind is a clean energy source. Windmills don’t burn fuel, so they don’t cause air or water pollution. Wind Energy is Clean.
One reason wind farms don’t produce more electricity is that they can only run when the winds are right. Sometimes the wind doesn’t blow at all. Sometimes the wind blows too hard. Most windmills only run about two-thirds of the time.
Discussion Questions What areas of the United States are best suited to generate wind power? Do you think Texas is a good area of the country to use wind farms? Since it is such a clean energy source, why don’t we use more wind power?