• Renewable and non-renewable sources of energy
  • Renewable: Biomass, Geothermal, HEP, Solar, Tidal, Wind, Waves
  • Non-Renewable: Coal, Oil, Natural Gas, Nuclear Power
  • Recall the features of each source of energy and explain the way back to its original source (usually the Sun!)
  • Only tidal (gravitational pull of the moon), geothermal (radioactivity from the rocks) and nuclear power (structure of the atoms) do not have the Sun as the source of their energy - all the others do.
  • Wind energy comes from the movement of air, which happens because of differences in air pressure (wind blows from high pressure zones to low pressure ones). The differences in air pressure are because the air is unevenly heated by the Sun because of lattitude and cloud cover.
  • Wave energy comes from the wind blowing on the sea and the wind's energy comes from the Sun
  • Biomass is anything living or dead that can be burned as a fuel - the energy from the Sun was converted into plant matter by photosynthesis... and plant matter is converted into animal matter when it is eaten by them!
  • HEP gets its energy from the Sun because the water is carried to high places by the water cycle and the water cycle is powered by the Sun's heat energy.
  • Solar power is used directly in two ways - in solar panels the Sun's heat (infra red energy) is used to heat water, in solar cells sunlight is converted into electricity.
  • Recall the problems and advantages of each source of energy
  • Increasing carbon dioxide in the atmosphere is causing global warming (the greenhouse effect) and this may cause catastrophic weather changes and flooding around the world.
  • The law of conservation of energy states that 'Energy is neither created nor destroyed, it merely changes from one form to another'.
  • Describe energy changes in a sytem using energy types such as kinetic, gravitational potential, elastic stored energy, light, sound, heat etc.
  • Simple energy change diagrams are called Sankey diagrams. They show how much of the energy input (source) on the left is converted into desired output on the right and unwanted output (down)