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pencil.gif (370 bytes) Making An Anemometer
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An anemometer is a a wind speed indicator. While a real one will accurately measure how fast the wind is blowing, this is only a model and will just give an approximation. You need to know the speed of the wind before you can use it for generating electricity.
You will need: Scissors,4 small paper cups, a marker or sketch pen, 2 strips of hard cardboard of the same length, ruler, stapler, thumb pin, sharpened pencil with eraser on the end, putty, or m-seal, a watch that shows seconds
Instructions:
1.Cut off the rolled edges of the paper cups to make them lighter.

2.Color the outside of one cup with the coloured pen.

3.Cross the cardboard strips so they make a plus (+) sign. Staple them together.

4. Take the ruler and pencil and draw lines from the outside corners of where the cardboard strips come together to the opposite corners. Where the pencil lines cross will be the exact middle of the cross.

5. Staple the cups to the ends of the cardboard strips; make sure the cups all face the same direction.

6. Push the pin through the center of the cardboard (where the pencil lines cross) and attach the cardboard cross with the cups on it to the eraser point of the pencil. Blow on the cups to make sure the cardboard spins around freely on the pin.

7. Place the putty outside your house. Stick the sharpened end of the pencil into the clay so it stands up straight.

Your anemometer is now ready for use!

Measuring Wind Speed
This anamometer cannot not tell the wind speed in miles per hour, but it can give you an idea of how fast the wind is blowing.

Using your watch, count the number of times the colored cup spins around in one minute. You are measuring the wind speed in revolutions (turns) per minute. Weather forecasters' anemometers convert the revolutions per minute into miles per hour (or kilometers per hour). Keep a record of the wind speeds you're measuring for the next few days.
Measure the wind speed at different times of the day. Is it the same in the morning; the afternoon; the evening? Move your anemometer to another location. Is it windier in other places? Do trees or buildings block the wind?

Wind speed is important for wind energy. Wind turbines -- which are the machines that change the movement of the wind into electricity -- need a constant, average wind speed of about 14 miles per hour before the wind turbines can generate electricity. That's why wind farms, where there are a lot of wind turbines grouped together, are located in windy spots.