Difference Between in Physics

Difference Between Alternator and Generator

This article presents the difference between alternator and generator. It explains how they are different from each other on the basis of structure, output, efficiency, etc. This article will thus help to get clear concepts about alternator and generator without any ambiguity. Here, the difference between alternator and generator is given in a tabular form which is very easy for understanding. Alternators and generators are the two different equipment for generating electricity. An alternator may be considered as a type of generator. The alternator is like a charging system for cars and producing electricity. Whereas the generators are used for the production of electricity at the large-scale. Both are converting mechanical energy into electrical energy. But, the main difference between alternator and generator is on the basis of spins and movements.

What is the alternator?

An alternator is a machine which produces the Alternating Current, by converting mechanical energy into electrical energy. Therefore, it is termed as an AC generator or the synchronous generator. In the alternator, electricity is produced when a magnetic field spins inside the windings of wire.

There are many types of alternators on the basis of the applications and design. Some of these are Marine type alternator, automotive-type alternator, Diesel-electric locomotive type’s alternator, and Brushless type alternator, etc. Alternators are conserving energy by using only the energy which is needed.

What is the generator?

Electrical generators are the machines which provide the electricity, during the no power supply from the power grid. In the generator the armature or windings of wire spin inside the fixed magnetic field and hence generating electricity.

Thus, Industrial generators are often mainly useful to supply the power backup for the electrical appliances at home or office. Also, this power supply will do all the work as the supply from the power grid. This power source is always useful in the scenario for the place where power grid supply is not possible at all such as in the mining and farming operations.

This is also applicable during new developments and construction locations. Some electrical generators are small as well portable. But the big generators are also there, which needs the proper and permanent installations. Industrial generators are very powerful and hence capable of maintaining the full power to the manufacturing facilities etc. There are some variants of generators as diesel generators, natural gas generators, propane generators, and bi-fuel generators.

Difference Between Alternator and Generator

Difference between alternator and generator

                                                                  Difference between alternator and generator

The important difference between alternator and generator

Parameter Alternator Generator
Definition It is the device that converts mechanical energy into AC electrical energy. This is a mechanical device that converts mechanical energy to either AC or DC electrical energy.
Output Current It always induces an alternating current. It may generate either alternating or direct current.
Energy Efficiency These are very efficient. These are less efficient.
Output These have a higher output. These have a lower output.
Energy Conservation It conserves more energy. It conserves less energy.
Polarization Polarization is not required. It is required.
Magnetic Field Its magnetic field rotates inside the stator. Its magnetic field is stationary or fixed where the armature winding spins.
Armature position Its armature is stationary. Its armature is rotating.
Rotation Per Minute Range These are having a wide range of RPM. These are having a low range of RPM.
Voltage Generation Alternators produce voltage only when needed. Generators produce a voltage at all times.
Charging of a Dead Battery Alternators cannot charge a dead battery, Generators can charge the dead battery.
Uses Alternators are mainly in use in the automobile industry as a charging system for the battery. Generators are widely used to produce large-scale electricity.


Output Current from the alternator can be reduced when the alternator speed reduced. The efficiency of the alternator can be reduced when it runs with low speed. When the temperature of alternator increased then the output current will be decreased.


A generator is like an energy engine, which converts kinetic energy into electricity. It consists of a stationary magnetic field, in which a rotating electromagnet i.e. armature spins and hence produces the electrical current.  The gasoline-powered generator is one variant, in which the internal combustion engine drives the rotating shaft and then turns the armature. Some other renewable types of energy, wind, and water are useful as different kinds of electricity generators.

FAQs on alternator and generator:

Q.1: What are the two classifications of the generator?

Solution: A generator is classified as an AC generator and a DC generator.

Q.2: What is another name of synchronous generators?

Solution:  Synchronous generators are also termed as Alternators.

Q.3: What are the different kinds of losses in a generator?

Solution: Following are the different kinds of losses in the generator: – Friction loss, Windage loss, Rotor copper, Stator copper, and Stator iron.




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2 responses to “Difference Between Concave And Convex Mirror”

  1. suma says:

    hey do you guys knows what is cconcave

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