Sources of Energy (part – 2)

Visit our educational YouTube channel :

Fossil fuels

These are the remains of prehistoric plants and animals which got buried deep inside the earth millions of years ago due to some natural processes. Fossil fuel is the major source of energy for generating the electricity in power plants.

Coal: It is the most abundant fossil fuel on the earth. It is mainly used as combustion fuel. It is the complex mixture of carbon, hydrogen and oxygen and some free carbon. Small amount of sulphur and nitrogen compound.

Coal formation

Coal is the product of plants which died millions year ago. The action of certain bacteria causes release of oxygen and hydrogen and its residue rich in carbon. As more material accumulated water squeeze out. Due to high temperature and pressure material becomes condensed and gases expelled out. The proportion of carbon continued to increase till it slowly changed into coal over a period of millions of years. This layer of carbon is called PEAT and show 27% of carbon.

  • Apart from peat, there is three another type of coal: lignite (28% – 30%), bituminous (78% – 87%) and anthracite (94% – 98%).
  • When coal is burnt, carbon is present in it react with oxygen to produce carbon-di-oxide and lots of heat.   

Coke is produced when coal is heating strongly in absence of air. Coke has high energy value and produce less smoke.

India has about 7% of world’s known coal reserves and these are mainly found in Bihar, Orissa and Madhya Pradesh. Coal supplies 50% of the country’s total energy requirement.  

Uses of coal

  • It is used as fuel in industries
  • It is used to produce electricity.
  • It is used to manufacture of fuel gases like coal gas.
  • When coal is heating strongly in the absence of air it changes into coke.
  • It is better quality fuel than coal because it produces more heat.