Energy is the capacity of doing work. It may exist in potential, kinetic, thermal, electrical, chemical, nuclear, or other various forms. There are, moreover, heat and work - energy is the process of transfer from one body to another.

Classification of sources of energy

Wood, coal petroleum, etc. are some of the energy sources of energy. They produce heat when they are burnt. Energy sources can be classified into two types: renewable and non-renewable.

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  Renewable sources: https://www.youtube.com/watch?v=pqzvUur7QRw
  


• Non-renewable sources: https://www.youtube.com/watch?v=A9Z8Ro4Z5b8
  

MAJOR SOURCES OF ENERGY

By now, you should have understood what "sources of energy" means. So now we will be talking about some of the major energy sources.

Solar energy: Solar energy is a renewable source. It is derived from the sun's rays. Solar energy is converted directly to electricity through solar photovoltaic panels. Solar power has grown in popularity since the 1970' s due to the oil crisis. Now, since solar energy comes from the sun let's talk a little about the sun. So, the sun is a big ball of fire and is very large in comparison to earth. By mass, the sun is so huge that even the total mass of the solar system members together becomes 0.0015^th part of the sun. The surface and centre temperatures of the sun are 5.7*10³ °C and 1.5*10⁷ °C respectively. At this high temperature, no substances can exist in solid or liquid states. Hence, the sun is a mass of very hot gases. The sun emits 2.7*10²⁴ KW energy every second. The earth receives a small fraction of the energy emitted by the sun due to a very large distance between the sun and the earth. The earth gets 2.6*10²² joule of energy every second.                                                                                          The given diagram is for the application of solar power in Nepal.                                   

  Advantages and disadvantages of solar energy

Traditional use of solar energy

• used as heat for cooking.


• to take the salt away from seawater.


• used by plants for the process of photosynthesis.


• to generate electricity with solar cells.


• used for preservations of fruits, vegetables, fish, etc.

Sun is the ultimate source of energy.

Nuclear fusion is the source of solar energy.

https://www.youtube.com/watch?v=pusKlK1L5To