Energy: Definition and Basics
Energy is something which cannot be seen directly but can be experienced and makes us able to do some work. In short ability to do some work by a body or system is called energy. We take energy in various forms like our food, sunlight etc. Without energy no system (including our body) can perform any task. Hence energy is the basic need of human society.
Energy can be experienced and is not visible directly. You can see the efforts made and the work being done but not energy. There are many other properties of energy. Most important of them is universal nature of energy.
Energy can neither be created nor be destroyed. It just changes its form.
We may see different forms or nature of works but the energy doing that work remains same. For example you convert chemical energy of coal into heat and that heat into electricity with the help of steam turbine and water and the same electricity can be converted into light energy from a LED (Light Emitting Diode). This shows how energy changes it form.
Energy: Various Forms
Energy exists in various forms, as stated earlier. Some very common forms of energy are as below :
- Electrical Energy
- Mechanical Energy
- Kinetic Energy (Due to Movement or Speed)
- Potential Energy (Due to Position or Height)
- Chemical Energy
- Atomic/Nuclear Energy
- Solar Energy
- Wind Energy
- Tidal Energy
- Sound Energy
- Heat/Thermal Energy
- Geothermal Energy
I will discuss these energies in detail in later articles.
Energy: Various Sources
All above forms of energy are extracted from various sources like Sun, Atoms, Wind, Chemical compounds, Sea etc. All these sources of energy are classified into two categories as given below:
Conventional/Non Renewable Sources of Energy
- Conventional/Non Renewable Sources of Energy
- Non-Conventional/Renewable Sources of Energy
are those sources which are being used since long time and cannot be renewed i.e. once used the cannot used again. Once you used such source for energy they cannot be used again. For example Coal, Diesel, Petrol etc.
Non-Conventional/Renewable Sources of Energy
are those sources which are relatively new and these can be renewed i.e. can be used again and again. Once you used such source for energy they can be used again to give energy to you. For Example Sun, Wind, Tidal Energy etc. These are discussed in detail at Non Conventional Sources of Energy : Basics, Advantages, Disadvantages and Challenges