1. Chapter 13 Energy and Power
Section 3
Energy Conversion and Fossil Fuels

2. Energy Conversions and Fossil Fuels
A fuel is a material that stores potential energy.
Fuels such as coal, petroleum, and natural gas are known as fossil fuels.
Fossil fuels contain energy that came from the sun.
Within its core, sun converts nuclear energy to electromagnetic energy.

3. Energy Conversions and Fossil Fuels
Ancient plants and animals converted the electromagnetic energy from the sun to stored chemical energy.
On Earth, remains of plants and animals are turned into coal over millions of years.
Stored chemical energy in coal is converted to thermal energy of steam when the coal is burned.

4. Energy Conversions and Fossil Fuels
Thermal energy is converted to mechanical energy as turbines in power plants are turned by the steam.
As the turbines turn electric generators, mechanical energy is converted to electrical energy.
Electrical energy is converted into many different kinds of energies, for example, the thermal energy in a toaster.

5. Energy Conversions and Fossil Fuels
Fossil fuels can be burned and release the potential chemical energy stored millions of years ago.
The process of burning is called combustion.
Combustion changes the fuel’s chemical potential energy to thermal energy.

6. Energy Conversions and Fossil Fuels
What is the process that produces the sun’s energy?
Nuclear fusion
What general statement can you make about the supply of fossil fuels, given what you know about their formation?

7. Energy Conversions and Fossil Fuels
Because fossil fuels are formed much more slowly than we are using them, they may become increasely scarce.