Non-renewable energy: fossil fuels

Oil and gas were formed from the remains of animals and plants that lived millions of years ago in the sea. These remains were covered by layers of sand and silt. Heat and pressure from the Earth's core turned them into oil and gas. The oil and gas were trapped between layers of impermeable rocks.

Coal was formed from dead plants about 300 million years ago. Back then, much of the Earth was covered by swamps. As the vegetation died, it decayed, slowly forming layers of peat. Over time this was covered with more sediment and compressed and heated to form coal.

Advantages of fossil fuels

  • They generate large amounts of energy quite cheaply.
  • As technology improves, more reserves can be accessed.
  • Locating where fossil fuels are is quite easy.
  • Oil and gas can be transported through pipelines.
  • The means for extracting fossil fuels is already in existence.

Disadvantages of fossil fuels

  • They release carbon dioxide when they are burnt, creating pollution.
  • Carbon dioxide contributes to the greenhouse effect and global warming.
  • Mining can create ugly scars on the landscape.
  • Mining can be dangerous, especially as the most easily accessible deposits are used up.
  • Oil spills can cause environmental damage.
  • Supplies are running out and new sources are harder to get to. Oil and gas are both predicted to run out within 100 years.
  • Oil is mainly produced outside the UK, so prices are set by other countries.