What is Energy?
Before learning about sources of energy, let’s understand what energy is. Classical description for energy is the ability of a system to perform work but because energy exists in so many forms, it is hard to find one comprehensive definition. In short, energy is the ability of a system to make things happen. It is a property of an object which can be transferred from object to object or converted to different forms but cannot be created or destroyed. There are numerous sources of energy. It can be chemical energy, electrical energy, heat/ thermal energy, mechanical energy, nuclear energy and energy in the form of electromagnetic radiation ie light.
Sources of energy contain energy in them if forms that cannot be used directly but living organisms require energy to stay alive. Therefore you must unlock this energy to get work done. Humans get energy from food which has this energy stored in form of chemical energy. Your body absorbs this energy from food and burns it to fuel your body so that you can run around and have fun. A candle has a lot of chemical energy but it has to burn for it be useful. This conversion of chemical energy to yield heat and light energy is burning. Burning is a process of converting chemical energy to heat energy and sometimes light too.
We must make one observation though, energy seems to have a shelf life. If you keep a hot object out in the open, it will cool after a while. Can you collect this energy back from the atmosphere? You will learn more about the flow of energy when you discuss the Laws of Thermodynamics. We have discussed a few sources now let’s discuss them in detail.
Difference Between Renewable and Nonrenewable sources of Energy
|The resources that can be renewed or replaced are called renewable sources of energy.||The resources that cannot be renewed once they are consumed are called nonrenewable sources of energy.|
|These resources do not cause any pollution to the environment.||
These resources cause pollution to the environment.
|Renewable resources are inexhaustible.||Non- Renewable resources are exhaustible.|
|Renewable resources are not affected by the human activities.||Non- Renewable resources are affected by the human activities.|
|Examples of Renewable resources- Air, water and solar energy||Examples of Renewable resources- Mineral, oil and Coal|
Natural Resources – Sources of Energy
The natural resources around us provide a variety of sources of energy around us. During the Stone Age, it was wood. During the Iron Age, we had coal. In the modern age, we have Petroleum and Natural gas. So how do we choose sources of energy?
Good sources of energy should have following qualities:
- Optimum heat production per unit of volume/mass used
- Easy to transport
- Least Polluting
Earlier coal was used pretty much everywhere, from domestic use to steam engines all the way to Titanic. One problem that coal faced was transporting large amounts of coal needed all around the world. Hence now world over energy use is shifting towards either diesel or electricity. This example shows how petroleum is better against coal on all the above parameters.
There are a two types of Sources of Energy classified by their popularity and use,
- Conventional Sources of Energy
- Non Conventional Sources of Energy
Difference Between Conventional and Non conventional Sources of Energy
|The resources which have been in use for a long time.||The resources which are yet in the process of development over the past few years.|
|These resources are exhaustible.||These resources are inexhaustible.|
|These resources cause pollution as they emit smoke and ash.||These resources are usually pollution free.|
|These resources are very expensive to be maintained, stored and transmitted.||These resources are less expensive due to local use and can easily be maintained.|
|Examples- coal, natural gas, petroleum, and water power.||Examples- solar, biomass, wind, bio gas, and tidal, geothermal.|
In this article, you learnt about the natural resources, energy, the sources of energy and what makes a good source of energy. Explore more such articles at Byju’s which provides detailed solutions to the questions of NCERT Book for Source of Energy so that one cam compare their answers with the sample answers given for this chapter.