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Energy transformation facts for kids

Kids Encyclopedia Facts
Energy from sunlight, water absorbed by the roots, and carbon dioxide from the atmosphere produce glucose and oxygen by photosynthesis

Energy transformations happen everywhere. Energy cannot be created or destroyed and it can't appear from nowhere or disappear. Instead it changes form.

Different situations in nature and some machines can change one form of energy to another.

An example of natural energy conversion is how the Sun is used by plants. During photosynthesis the suns energy is transformed into the chemical energy which is the food for the plants.

An example of a machine making an energy transformation is how wind farm turbines turn mechanical wind energy into electrical energy.


Examples of sets of energy conversions in machines

A coal-fired power plant involves these energy transformations:

  1. Chemical energy in the coal is converted into thermal energy in the exhaust gases of combustion
  2. Thermal energy of the exhaust gases converted into thermal energy of steam through heat exchange
  3. Thermal energy of steam converted to mechanical energy in the turbine
  4. Mechanical energy of the turbine converted to electrical energy by the generator, which is the ultimate output

In such a system, the first and fourth steps are highly efficient, but the second and third steps are less efficient. The most efficient gas-fired electrical power stations can achieve 50% conversion efficiency. Oil- and coal-fired stations are less efficient.

In a conventional the following energy transformations occur:

  1. Chemical energy in the fuel is converted into kinetic energy of expanding gas via combustion
  2. Kinetic energy of expanding gas converted to the linear piston movement
  3. Linear piston movement converted to rotary crankshaft movement
  4. Rotary crankshaft movement passed into transmission assembly
  5. Rotary movement passed out of transmission assembly
  6. Rotary movement passed through a differential
  7. Rotary movement passed out of differential to drive wheels
  8. Rotary movement of drive wheels converted to linear motion of the vehicle

Other energy conversions

Oaxaca I Lamatalaventosa Wind Farm
Lamatalaventosa Wind Farm

There are many different machines and transducers that convert one energy form into another. A short list of examples follows:

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Energy transformation Facts for Kids. Kiddle Encyclopedia.