Skip to content →

Alternator vs Generator According to their Differences

Functionally, both alternator and generator are devices that work by converting mechanical energy turns to electrical energy. Even though so, there are plenty of differences between both in terms of structure, efficiency, output, supply, etc. Read more about detailed explanation of alternator vs generator distinctions and each of their specification in the following.

Alternator vs Generator

What is Alternator?

Alternator, in a way, is a type of generator. It is often considered as the enhanced version of it. This electricity generating system transforms mechanical energy into electricity by alternating current (AC) – electric current that reverses its direction in constant interval (normally sixty times each second). It has rotating magnet that producing the current to conduct energy and that’s how it’s able to provide electricity.

What is Generator?

Generator, similar to alternator, also turns mechanical into electrical energy. The most fundamental differences, is that generators produces both alternating current (AC) and direct current (DC). This system has rotating rotor that yields electricity and establishes magnetic field, thus delivering the required energy to whirl the armature.

AC vs DC Comparisons

Here are the basic differences of alternator vs. generator:

1. Definition          

  • Alternator: a device that transforms mechanical energy into electrical energy in AC.
  • Generator: a device that transforms mechanical energy into electrical energy in AC or DC.

2. Size

  • Alternator: Generally smaller in terms of physical.
  • Generators: Normally larger and needs more room to fit in.

3. Usage

  • Alternators: primarily used for automobile purpose as system of battery charging.
  • Generators: mainly used to generate electricity in larger scale.

4. Output Current

  • Alternator: always produces an alternating current.
  • Generator: creates either direct or alternating current.

5. Input Supply

  • Alternator: uses stator as input supplier.
  • Generator: uses rotor as input supplier.

6. Voltage Production

  • Alternator: delivers voltage when required only.
  • Generator: delivers voltage constantly.

7. Magnetic Field

  • Alternator: its magnetic field rotates within its stator.
  • Generator: its magnetic field is in permanent place where armature is whirling.

8. Armature Movement     

  • Alternator: stationary.
  • Generator: rotating.

9. Range of RPM (rotation per minute)

  • Alternators: high RPM range.
  • Generators: low RPM range.

10. Capability to charge dead battery

  • Alternators: incapable
  • Generator: capable

11. Energy Efficiency         

  • Alternators: highly efficient.
  • Generators: generally less efficient.

12. Polarization After Installation

  • Alternator: doesn’t require polarization.
  • Generator: requires polarization after installation.

13. Brush Efficiency

  • Alternator: the brush is more efficient and durable.
  • Generator: in general, its brush is less efficient than alternator.

How Does Alternator Work?

Alternator is mainly used in the industry of automotive. It is a device that used to turns mechanical energy to electrical in order to charge battery inside a car. Its mechanical energy comes from a rotating magnet, in which the produced magnetic fields are resulting in the transformed magnetic flux to generate electricity current. These devices distribute even currents, without having to convert to direct current.

In terms of efficiency of alternator vs. generator, alternator is winning because it produces energy only when required. As mentioned before, it is can be said as the upgraded version of how the generator system works, by minimizing the needed energy and the amount of wasted energy. Moreover, it doesn’t require polarization after its installation process is done.

How Does Generator Work?

Generator is a mechanical device with rotor within. Its rotor is located within the magnetic field and comprised of looped wires. When these looped wires rotate, that’s when the electricity is produced. Its magnet stays in fixed place and generates magnetic field, and the mechanical energy that’s produced is used to whirl the armature.

Generator consumes all the produced energy in ordure to deliver voltage. That’s why in alternator vs. generator, the latter is more commonly used to generate electricity in large scale. This device requires to be polarized after it is installed.

The Different Types of Generator

Below are four of the most commonly found types of generator, which are differentiated based on their applications:

Standby generators

These generators are used to automatically deliver power as backup source when the utility power is off. They can be found more in commercial buildings, residential apartments, and hospital.

Portable generators

This type of generator is very practical to be used during the times of calamities or natural disaster, when electrical black-outs or power outages usually happen. Portable generators fit more for personal properties and smaller scale commercial establishments such as shops or local retail outlets. They are also common to be used for outdoor activities that require electricity temporarily such as camping, tailgating, or other outdoor events.

Industrial generators

Generators that are used for industrial purposes are extremely different from those which are used for residential or smaller commercial buildings. These generators are designed to deliver optimum performance under tough circumstances and to have sturdier physical. They are also built to produce higher power, which may range between 20 kW to 2,500 kW; 1 to 3 phase supply; and 48 to 120 volt. Normally, this generator types is more customized than the other categories.

Inverter generators

Inverter is a more modern type of generator – it uses rectifier and generates AC power, which then can be turned into DC and transformed back into AC in order to provide more stable current for sensitive appliances. They can be used for both functional and recreational purposes, even for vehicles that require specific frequency and voltage values. Physically, inverter powers are usually compact and lightweight.

Advantages of Using Alternator vs Generator

While the basic function of both devices is quite similar, which is to produces electrical energy; there are plenty of technical differences of alternator vs. generator. It what makes them unique and suitable for different applications for the users.

In general, people who use alternators choose the equipment because of its simplicity. This device is also able to generate higher output when being compared to generator. It is also, in fact, a more reliable tool than generator.

Even though so, when you need to generate electricity in larger scale, it is more ideal to use generator. The lacking aspects that this device has when the comparison of alternator vs. generator comes up, are compensated by the multiple services offered. They can be used as DC motor as well, by putting power into its shaft.

Published in Blogs


Leave a Reply

Your email address will not be published. Required fields are marked *