The sun is the source of all life on our earth. Every form of energy, except for atomic energy, can be traced back to the sun. Happily, the earth is at the best possible distance from the sun for the sun's heat to provide this energy for life. Energy from sunlight is used by plants to make food from air, water, and the minerals in the soil. This energy is stored by plants who are the primary producers in ecosystems.

Energy sources such as the fossil fuels of coal, petroleum, and natural gas are really just ancient stockpiles of the sun's energy stored in plants and the animals that ate those plants that are thousands or millions of years old. These fuels came from plants that used sunlight when they lived long ago. When these plants died, they fell to the ground where their remains piled up over thousands or millions of years. As this pile grew large, the remains at the very bottom became pressed together. Over time, these remains changed. Some became a gas--natural gas. Some became a liquid--petroleum. Some became a solid or a rock--coal. We use these forms of energy to power vehicles, heat homes, and run industries. Fossil fuels are considered nonrenewable sources of energy because they cannot be replaced once they are used up.

Sample some of the following activities to learn more about different energy cycles.


Places To Go    People To See    Things To Do    Teacher Resources    Bibliography

Places To Go

The following are places to go (some real and some virtual) to find out about energy cycles.

Biofuels Basics
Biofuels are controversial renewable energy sources because they can have a negative impact on the environment by using large amounts of waters and fertilizers. Visit the cornfields of the midwestern United States to learn about growing corn, rapeseed, and other crops that produce ethanol and bio-diesel.
Coal Basics
Visit the swamplands that existed at the time of the dinosaurs. Those marshy, wet areas formed the basis for today’s coal deposits. Coal is called a fossil fuel because it was formed from the ancient remains of dead plants and animals.
Deforestation in the Amazon
Travel to the rainforests of Brazil. Enormous tracts of rainforest lands are being cleared to grow soybeans to be used for biofuels. The burning of rainforest acres causes the climate to change and less rain to fall.
Hoover Dam
Dams have been constructed around the world to divert the flow of a river into hydroelectric power plants. Turbines and generators inside the plant are used to change water from mechanical energy into electrical energy.
Iowa: Land of Corn and Wind Turbines
Then travel to Iowa to experience how wind power is providing energy.
Pelamis, World’s First Commercial Wave Energy Project, Agucadoura, Portugal
Renewable energy is energy that comes from sources that cannot be used up, such as the wind or the sun. Travel to Portugal where they are experimenting with generating energy from ocean waves to produce renewable energy for homes in Portugual that are close to the ocean’s coastline.
The Sun
Virtually visit the sun. The sun makes all life on our planet possible. It provides energy for everything on earth.

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People To See

How To Love a Turkey Vulture
Visit with a turkey vulture. Vultures are sometimes called buzzards. Buzzards play a key role in the energy cycle by feeding on the carcasses of dead animals.

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Things To Do

Comparison of Various Energy Sources
How does solar power compare to wind power or to refuse-based power? What are the advantages and disadvantages of coal power and nuclear power. Find out here.
Energy Industry Study Program
The energy we use comes from different energy sources. These sources are divided into two groups -- renewable and nonrenewable.
The Food Timeline
Find out what people throughout history ate. When was popcorn first eaten? When was Spam first eaten?
Learn how to spot energy hogs and lower your energy consumption.
How Food Works
Ever wonder what, exactly, you are putting in your body when you eat? Would you like to know the real difference between a "fat" and a "carb"? Learn all about food and how your body uses it!
How Stuff Works: Batteries
Batteries are all over the place -- in our cars, our PCs, laptops, portable MP3 players and cell phones. A battery is essentially a can full of chemicals that produce electrons.
Ice Cream
Ice cream is an important part of the energy cycle for all Americans. The average American eats about a ton of ice cream in his or her lifetime. Americans eat more ice cream than any other people in the world.
Learning About Fossil Fuels
Explore coal, oil, and natural gas as sources of energy.
NASA Space Shuttle - Food for Space Flight
According NASA, astronauts select their menus approximately five months before their flight. The menus are analyzed for nutritional content and corrections are made to any nutrient deficiencies based on the Recommended Dietary Allowances.
National Wind Technology Center
Learn about the benefits of wind power from the National Wind Technology Center (NWTC).
PlanetPals - The Food Chain
Find out about producers and consumers and the food chain.
Science Made Simple: Static Electricity
Figure out the energy that comes from rubbing your feet on carpet.
Science Museum of Minnesota: From Windmills to Whirligigs
Discover the power of the wind. Meet Vollis Simpson and his windmill-powered whirligigs.

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Teacher Resources

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  • Ganeri, Anita. The Hunt for Food. Brookfield, Conn.: Millbrook Press, 1997.
  • Kalman, Bobbie. What Are Food Chains and Webs? New York: Crabtree Pub. Co., c1998.
  • Lauber, Patricia. Who Eats What?: Food Chains and Food Webs. New York, NY: HarperCollins, c1995.
  • Maynard, Jacqui. I Know Where My Food Goes. Cambridge, Mass.: Candlewick Press, 1999.
  • Riley, Peter D. Food Chains. New York: Franklin Watts, 1998.