The following Topics and Sub-Topics are covered in this chapter and are available on MSVgo:
Did you know that India ranks 3rd in the world to consume energy after China and the United States?
The basic definition of energy is easy to understand.
The capacity for doing any action can be defined as energy. It is conservative. A simple example of the energy can be lighting a candle where you are converting the chemical (potential) energy into the light and heat energy. It exists in many forms like electrical energy, solar energy, hydro energy, thermal energy, etc.
You might have come across the formula for energy, i.e.
Energy = Power x Time
If a 30-watt lamp is turned on for an hour, how many joules of electrical energy is converted by the lamp?
After applying the formula,
= 30 watts x 3600s
= 108,000 joules
Power here is in watts and time is in seconds, and the answer is in joules.
Renewable Sources of Energy
The renewable energy sources are the natural resource that can replenish quickly after their use. These energy sources are available to us in abundance and are environment-friendly and sustainable.
Some of the renewable sources are:
Solar energy is the heat and light that comes from the sun. We use the sun’s energy with the help of the Photovoltaic cells that convert solar energy to electricity with the help of silicon present in them. One can, hence, use the electricity for a variety of purposes. Some examples that use these cells are solar cookers, large solar cells, etc.
Solar cookers have a lot of benefits like:
The demerit of a solar cooker is one cannot use it during night time. Hence, it becomes useless when the weather is cloudy, or one needs to cook after sunset.
What do you understand by wind energy?
Wind energy is utilizing wind to convert kinetic energy to mechanical energy and, as a result, generate electricity.
It is a renewable source of energy that is environment-friendly and clean. Wind energy’s primary use is to generate electricity, drive windmills, propel sailboats, and many more.
Since the early 20th century, we have been generating energy through wind turbines. The wind pushes a propeller through a mechanical system that rotates the generator’s rotor and produces electricity.
Geothermal energy is the energy which we obtain from the Earth. You might wonder how the Earth serves as a source?
Well, this type of energy is obtained from rock formations and the fluids within those formations. Magma is one of them, and it forms when heat melts rocks.
This magma is collected deep in the Earth, and the place where it accumulates is called “hotspots.” When water flows through these hotspots, it generates steam, which can be used to produce electricity.
The ocean covers 71% of the earth’s surface, and we can obtain a fair amount of energy from it. The main form of ocean energy is ocean thermal energy.
The difference in the temperature between water at the surface and depths gives rise to thermal energy in the oceans. The hot water boils the ammonia to form vapors, and it moves the turbine. Coldwater condenses the steam back to liquid form.
Dams are one of the common examples of water energy or hydro energy. When a flowing river is stored in a high–rise dam and then flows down the damn, it converts the potential energy to kinetic energy. This kinetic energy is used to drive the turbines to produce electricity.
The turbines are connected to generators, and in turn, they generate electricity. In this case, hydro energy is converted to electrical energy.
Water is available to us in abundance; hence, it is a good source of electrical energy.
Non renewable sources of energy are present in a limited quantity and are exhaustible. Once they are utilized, it takes millions of years to return to their original form and get replaced or replenished. Some of them are coal, natural gas, oil, etc.
Some non – renewable sources are:
In thermal power plants, coal and petroleum are combusted to produce heat, which generates electricity.
Fossil fuels are an excellent source of electricity. Fuels like coal, gas, oil are combusted to produce steam. The steam produced by these fossil fuels generates electricity for our homes.
Nuclear energy is generated through nuclear fission, which produces heat and runs the turbine to generate electricity.
Nuclear power plants control the process of nuclear fission and generate electricity. Uranium (U-235) is mostly used in these power plants to generate nuclear energy. This element is very rare and a non – renewable resource.
There are primarily two types of energy sources: renewable and non-renewable. Both have their advantages and disadvantages. It is important to learn about these sources to know how things work around us and what drives them.
1. What are the main sources of energy?
The primary sources of energy are fossil fuel energy, nuclear energy like coal, natural gas, oil, etc., and renewable sources like water, wind, geothermal products like magma, sun, etc.
2. What do you mean by sources of energy?
A source from which you can obtain useful energy directly or through conversion in abundance is energy sources. Energy can be converted from one form to another easily.
3. What is energy and sources of energy?
Energy is the power that is obtained from our natural resources. It exists in many forms like electrical energy, solar energy, hydro energy, thermal energy, etc. Any source from which you can obtain useful energy directly or through conversion in abundance is a source of energy.
4. What is the cheapest energy source?
Sunlight and wind are the cheapest sources of energy.
5. Which power source is most efficient?
Sun is the most efficient power source for a variety of purposes. It is used in manufacturing industries. The wind is also a very efficient source. Both of these energy sources are renewable and environment-friendly.
If you want to learn more about sources of energy, make sure to get the MSVGo app – a vast resource of videos, educational material and interactive methods of learning that will help you understand the concepts quickly. MSVGo has a large video library that uses visualizations to enhance both learning and teaching and makes concepts easier to grasp.