1. Wind and Solar Energy

2. http://www.neok12.com/php/watch.php?v=zX5d 71630051745572506451&t=Energy-Sources What else might there be that is NOT mentioned in the video?

3.  Wind is air in motion (What kind of energy is this?).  It is caused by the uneven heating of the earth’s surface by radiant energy from the sun.  Wind direction is shown by a wind vane, it points towards the source of the wind.  Wind speed is measured using an instrument called a wind gauge or anemometer.

5.  Nope!  Since ancient time people have harnessed the wind’s energy.  Over 5,000 years ago Egyptians used the wind to sail ships on the Nile.  In Holland windmills grind wheat and other grains.  In the colonies windmills grind grain and corn, pump water and now…make electricity!

6.  Basic parts: blades, shafts, gears, a generator, and a cable.  The amount of electricity produced depends on the size.  A small turbine may power one home. Large turbines can power up to 1,000 homes.  Sometimes grouped together to form a grid.

7.  http://www.neok12.com/php/watch.php?v=zX 5760535f4f516f1b6d705d&t=Energy-Sources http://www.neok12.com/php/watch.php?v=zX 5760535f4f516f1b6d705d&t=Energy-Sources

8.  How does a site get chosen for a wind power plant?  Height? Closed or open spaces?  Usually built in rows facing into winds. Spacing is important. Too close or too far won’t be as beneficial.  Best sites: Hilltops, open plains, mountain passes, nears coasts, or large lakes.

9.  Only a small amount of electricity is produced by wind….Why?  Most turbines only run 18 hours a day.  People worry about birds and bats being injured by the turbines.  Some people believe they produce too much sound.  They affect the view of the landscape.  Do the benefits out weigh the negatives?

10. Harnessing the Sun’s energy

11.  The sun is a ball of hydrogen and helium.  The four hydrogen nuclei fuse producing one helium.  During fusion the nuclear energy is converted into radiant energy and thermal energy(heat).  The radiant energy is what we feel on earth, it travels in electromagnetic waves or rays.  What are examples of radiant energy?  Different energy depending on the length of ray: The shorter the wave the more energy it contains.

12.  Speed= 186,000 miles per hour.  Each day the earth receives enough solar energy to supply our nations energy for an entire year!  Most of the solar energy is lost in space before it reached earth.

13. PASSIVE SOLAR HOMEACTIVE SOLAR HOME  Designed to let in as much light as possible.  Acts as a big solar collector.  The light passes through the windows and heats the walls and floor inside.  The heat is trapped.  Does not depend on mechanical equipment.  Uses special equipment to collect sunlight.  Face south on the rooftop to get the winter sun.  Dark color plates are inside the boxes to absorb sunlight and change it into heat.  Air flows through the box, heating up then being distributed though the house.

14.  Placed on the south side where is can collect sunlight.  Hot water is piped through the house.  More then one million homes and 200,00 business in the U.S. use these.

15.  Solar energy can be used to produce electricity in two ways; photovoltaics and solar thermal.  We will talk about photovoltaics or PV cells or solar cells first.

16.  Comes from the words meaning photo and volt. What do these two words mean? What can you infer from the meanings?  What are some things you can think of that use this kind of power?  Solar cells made of Silicon, which also makes up sand.  Provide energy to anything powered by electricity or batteries.

17.  Sunlight strikes the solar cell which causes electrons to move around.  This action starts an electrical current.  Sunlight turning into electricity happens instantly and silently.  No mechanical parts.  It costs 10-20 cents/kilowatt hr whereas “regular” electrical costs about 9 cents/kilowatt hr.

18.  http://www.neok12.com/php/watch.php?v=zX 0055756164640a50060173&t=Energy- Sources http://www.neok12.com/php/watch.php?v=zX 0055756164640a50060173&t=Energy- Sources

19.  Heats a liquid using a mirrored surface  Liquid makes steam to produce electricity much like coal plants.

20.  It’s FREE!  Supplies are unlimited.  Does not pollute!  Does not damage the environment.  It cannot be controlled by any one nation.  If we can improve the technology we will never face shortages again.

21.  http://www.neok12.com/php/watch.php?v=zX 4501794c04647766705041&t=Energy- Sources http://www.neok12.com/php/watch.php?v=zX 4501794c04647766705041&t=Energy- Sources