Science Behind How a Generator Works

The Science Behind How a Generator Works

A generator is a device which generates electricity by converting mechanical energy into electrical energy. The fuel used for making power includes coal, oil, wind, natural gas and other sources. The complexity of the device increases with the increase in the output. The generators can be classified into three types; inverters, portable generators and standby generators. The generator works on faraday’s laws which states that whenever a conductor is placed in a magnetic field induces an electromagnetic field. The two primary elements of the generator are the motion of conductor placed in the magnetic field and a magnetic field.

The Working of a Generator

Science Behind How a Generator WorksIf you want to understand how a generator works, then we need to know what components make the generator and the basic principle on which it operates. According to Faraday’s law, any object which passes through a magnetic field is capable of generating electricity. Generators are made of copper materials and powerful magnets to create an electromagnetic field.

In the early years, the generators are attached to generators or hand crank, which triggers the movement. The generators were used to power homes, and turbines were required to run the generators to produce hydroelectricity. Today generators have come a long way and are used for a whole range of different things. From running the electricity for a whole house to generators used for camping to new technology with inverter generators that are super efficient and ultra quiet to run.

The generators consist of magnets with the magnetic field around triggers electric current every time it rotates. The continuous movement of the conductor generates a regular supply of electricity.

It is quite evident that the generator directly does not produce electrical energy but converts mechanical energy supplied to it with the help of moving electrical charges in the wire. The electric charges deliver the output as electricity.


The working of the generator which converts mechanical energy into electrical energy can be explained using a water pump example. The water pump is used to pump up the water from the underground or trigger the flow of water using electrical energy but does not on its product water.
The generator works on the same technology except it pushes electrons in place of water. The magnet in the generator pushes particles using particular force which results in converting mechanical energy into electric energy.

The Science Behind Working of Generator

The generator works on the electromagnetic induction phenomena, which is explained by Michael Faraday. Michael Faraday discovered the theory of electromagnetic induction in 1831, which states that when a conductor is placed in a magnetic field, voltage is induced in it. It is the same mechanism in the generator which produces mechanical energy in the turbine. The internal combustion engine is the primary source of mechanical energy in the generator. When electric voltage is produced as output, a part of it flows into the coil which creates a magnetic field.

The Faradays law discovered the interaction of a magnetic field with an electric circuit to produce electromotive force. The phenomenon is termed as electromagnetic induction.

Faraday’s law of electromagnetic induction states that current will be induced in a conducting material when exposed to a magnetic field. The law of induction explains that the working principle of generators, inductors, motors and transformers. Faraday conducted an experiment using a magnet and coil and discovered the phenomenon of induction, and hence the law is named after him. During his investigation, he found that electromagnetic force is induced in the coil when the magnetic lines are passing through the conductor changes.

Faraday’s Experiment of Electromagnetic Induction

Science Behind How a Generator WorksIn this experiment, Faraday takes a coil, and a magnet connects the galvanometer. When the magnet is at rest there is no deflection shown by the needle in the galvanometer and is at zero position only. But, when the magnet is moved closer to the coil, the needle of the galvanometer shows a deflection in a specific direction.

However, holding the magnet in a stationery position does not record any deflection of the needle in the galvanometer, which means it returns to zero. Again, when the magnet is moved away from the coil in the opposite direction, there is a defection recorded in the galvanometer. But when left to remain in the same position, the needle points zero again. Similarly, when the magnet is kept stationary, and the coil is moved close to the magnet, the needle in the galvanometer deflects. The rapid change in the movement of the magnetic field, the higher is the EMF recorded in the coil.

From the above experiment, Michael Faraday concluded that whenever there is relative motion between a magnetic field and conductor the magnetic lines passing through the coil changes inducing a voltage across the coil. Making the above experiments as a basis, Michael Faraday formulated two laws on electromagnetic induction. These laws are known as Faraday’s laws of electromagnetic induction.

Faraday’s First Law

Science Behind How a Generator WorksChange in the magnetic field of a conductor will cause an electromagnetic force to be induced in the conductor and is called induced emf. And when the circuit is closed the current circulates in the circuit which is called induced current.

Faraday’s Second Law

Science Behind How a Generator WorksFaraday’s second law states that the magnitude of the electromagnetic force induced in the conductor is equal to the rate of change of magnetic field that links to the conductor.

Faraday’s laws are simple, basic and significant laws of electromagnetism. The law has its application in most of the machines that use electricity including generator, medical field, industries and others.

  • Faraday’s laws are the basis for the functioning of power transformers.
  • Faraday’s law of mutual induction forms the basis for the working of an electrical generator.
  • The induction cooker which is the fastest way of cooking works on the principle of mutual induction. The change in the magnetic field is produced when the current flows through the copper wire coil below the cooking container. The changing magnetic field induces electromagnetic force resulting in creating a current which turns into heat.
  • The velocity of certain fluids is measured using an electromagnetic flowmeter.
  • The electromagnetic induction is also used in musical instruments such as electric violin etc.

Apart from the above electromagnetic induction is used in many other electrical appliances.