IB DP Physics: HL复习笔记8.1.3 Primary & Secondary Energy Sources

Primary Energy Sources

  • Primary energy sources are found in nature and have some stored energy capacity
  • To be a primary energy source, there must be:
    • No processing or refining
    • Stored energy must occur naturally in the source
  • The definition of a primary energy source is: 

Energy sources found in the natural environment

  • Examples of primary energy sources include fuels such as:
    • oil
    • kerosene
    • coal
    • Nuclear material for fission
  • Primary energy sources can also be renewables such as:
    • Geothermal
      • Heat from the Earth's crust
    • Hydroelectric
      • Energy stored in water higher than a set of turbines
    • Solar power
      • Radiation energy from the Sun
    • Wind power
      • Kinetic energy contained within the wind
    • Tidal power
      • Kinetic energy contained within the tides
  • In each example listed above, the primary energy source is the focus of the collection
    • Once processing or conversion of energy from one form to another occurs, then it is no longer a primary energy source

Secondary Energy Sources

  • Secondary energy sources come from the use or processing of primary energy sources
  • Often the secondary energy source is electricity
    • It can also be petrol, biofuel and heat
  • The definition of a secondary energy resource is:

Useful transformations of the primary resources into energy

  • Examples include:
    • Stored gravitational energy from water is converted into electricity in a hydroelectric plant.
    • Oil is refined to produce petrol that can be used to power a car
    • Coal is burnt to produce heat on a fire
  • The table below shows examples of primary and secondary energy sources as they are used to produce useful energy