Types of Non-Renewable sources of energy

Coal :

• Coal is formed by the prolonged action of geological forces on the plant and vegetal matter accumulated below the earth crust. The process is called “COALIFICATION”. Coalification is both time and force dependent. Coalification brings following changes to the accumulated plant:
  

  

• The formation of peat beds involves a combination of woody growth in wet, swampy places with favourable biochemical conditions. As coalification proceeds in the sequence given anove, both physical and chemical changes occur. The chemical changes are given below:
  
  
• Oxygen decreases from 40% for wood to 30% for peat, 20% for lignite, 5% for bituminous and 2% for anthracite coal.
  
  
• Volatile matter decreases from about 70% for wood to 5% or less for anthracite coal.
  
  
• Increase in carbon from about 30% for wood and peat to 90-95% for anthracite coal.

Petroleum :

Petroleum is formed in the earth's crust from the accumulated vegetal and animal matter metamorphic processes similar to coalification.

From crude petroleum; gasoline, lubricating oil, fuel oils etc. are obtained.

Natural gas :

It is used directly