Law of Conservation of Energy states that, “Energy can neither be created nor be destroyed. It can only be transferred from one state to another.” For example, a burning candle transforms chemical energy into light & heat energy.
Let’s try and understand energy in simpler terms. It is simply something which we require to carry out our day-to-day activities. We require energy to study, play games, to climb up or down the stairs. In fact, we need the energy to eat food as well. Hence, we can define energy as the capacity to do work. It can exist in various forms such as
· Potential energy
· Thermal energy
· Nuclear energy
· Kinetic energy
· Chemical energy
· Electrical energy & many more
There are two kinds of energy sources:
1. Renewable sources of energy: These sources of energy can be replenished after their consumption. They provide us with a continuous supply of clean energy.
2. Nonrenewable sources of energy: These sources of energy are cannot be regenerated by natural means hence, they must be used judiciously.
Major Renewable Sources of energy are:
1. Wind Energy: Wind is a form of energy that is used to create electricity. Wind energy is also used to fly kites. We can also produce electricity using wind energy by using the kinetic energy of air.
2. Solar energy: The heat and light from the sun is harnessed by using various technologies such as artificial photosynthesis. This form of energy has been used by mankind for cooking, heating & much more.
3. Biomass: It can be def ined as the organic material which comes from plants and animals. It is used to produce heat & electricity. There are various materials that can be used to make biomass fuel such as manure, wood, food crops, industrial & municipal waste, etc.
4. Geothermal energy: It’s a renewable form of energy that is derived from the core of the earth. This thermal energy, is present in the earth’s core and was generated during the creation of the planet. Humans have learned to capture this form of energy from our planet’s within, and harness it to be used in cooking, heating the spaces, etc.
5. Hydropower: We can also call it water power.
It is also known as hydroelectric power where the kinetic energy of falling water is used to produce electricity. It is sometimes used to power machines as well. The force of water from rivers and other sources of water is used to generate mechanical energy. This source of energy is considered a medium of sustainable energy. Other applications of hydropower are compressed air and watermills.
Major Non-Renewable Sources of energy are:
The non-replenishable sources of energy are nuclear energy & fossil fuels like coal, petroleum & natural gas.
Fossil Fuels: These were formed millions of years ago by the decomposition of dead organisms. Fossil fuels include coal, petroleum & natural gas. When plant matter got decomposed in conditions of high pressure & temperature, that is how coal was formed. Similarly, petroleum was formed after the decomposition of the remains of plants, marine animals, bacteria, and algae under high temperature & pressure. To form natural gas, multiple layers of animal & plant matter were brought under extreme pressure & heat, for millions of years. The fossil fuel (or hydrocarbon) thus formed in a gaseous state was termed natural gas.
Nuclear Energy: The energy which is released when a nuclear reaction takes place, is called nuclear energy. These reactions can be either nuclear fission (breaking of the nucleus into more fragments) or nuclear fusion (when two nuclei come together to form one). The most widely used fuel for nuclear energy is Uranium.