Energy

Almost all energy we use comes originally from the sun. Fossil fuels are plant and animal matter that decayed tens of millions of years ago and have been compressed and heated turning into coal, oil and gases. Of course, plants get energy from the sun and convert it through photosynthesis. Animals in turn eat plants converting the stored energy into energy to keep themselves alive.  

Wind is created because of differential heating of land and water areas by the sun creating movement of air from one area to another. Geothermal energy is residual heat of the earth, which was created billions of years ago in the formation of the earth and the solar system. So, we can trace all energy back to the source...the nearest star, our sun.

Energy is in everything.  We use energy to do everything we do, from making a jump shot to baking our favorite cookies to sending astronauts into space -- energy is there, making sure we have the power to do it all

We use all these energy sources to generate the electricity we need for our homes, businesses, schools, and factories.  Electricity "energizes" our computers, lights, refrigerators, washing machines, and air conditioners, to name only a few uses.  

We use energy to run our cars.  The gasoline we burn in our cars is made from oil.  We use energy to cook on an outdoor grill or soar in a beautiful hot-air balloon.  The propane for these recreational activities is made from oil and natural gas.  

There are two types of energy -- stored (potential) energy and working (kinetic) energy.  For example, the food you eat contains chemical energy, and your body stores this energy until you release it when you work or play. 

It comes in different forms -- heat (thermal), light (radiant), mechanical, electrical, chemical, and nuclear energy. 

All forms of energy are stored in different ways, in the energy sources that we use every day.  These sources are divided into two groups-- renewable (an energy source that we can use over and over again) and nonrenewable (an energy source that we are using up and cannot recreate in a short period of time).  Renewable energy sources include solar energy, which comes from the sun and can be turned into electricity and heat.  Wind, geothermal energy from inside the earth, biomass from plants, and hydropower from water are also renewable energy sources.  

Non-Renewable Sources of Energy

Renewable Sources of Energy

Conduction, Convection, and Radiation

 Energy project

  Energy Quiz (give it a try!!)

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