How Do Generators Work: What You Need to Know

What is a Generator?

Over the years, generators have provided power to many households, as well as commercial and industrial sectors. Tracing back as early as 1831, generators are practical and useful equipment that supply power when an outage from the local grid occurs. They can prevent disruptions of business operations and daily activities.

Depending on their applications, generators are available in various physical and electronic configurations. Industrial generators are usually used to supply backup power and electricity to businesses, industrial plants, and the like. However, generators are also used as a main power source in various locations where a local electric grid is difficult to access or unavailable, such farming or mining operations, as well as in construction or new development projects.

So what are the principles behind generators? How do generators work and create electricity?

How do Generators Work?

A common misconception is that the generators create electricity. Truth be told, a lot of physics is involved before a generator can actually supply power.

All kinds of generators, from small to big, work based on the principle of electromagnetic induction. Generators actually convert chemical or mechanical energy into electrical energy. 

In this principle, 19th century British scientist Michael Faraday made a discovery that when an electrical conductor moves in a magnetic field it creates electrical charges that can be directed to induce a flow of current. Faraday’s law also states that any object which passes through a magnetic field can generate electricity.

Since generators are made of powerful magnets and copper materials, they are capable of creating an electromagnetic field.

There are basically three types of generators: standby generators, portable generators, and inverters. Generators may have up to ten main components. Each plays a crucial role in generating electricity:

  1. The engine supplies the energy to run the generator. The amount of electricity a generator can provide is determined by the power of the engine.
  2. Fuel System makes it possible for the generator to generate the energy needed. At minimum, it includes a fuel pump, a fuel tank, and a pipe that connects the tank to the engine.
  3. A cooling system makes sure that the generator doesn’t overheat, since the machine produces a lot of heat.
  4. The exhaust system directs and removes the fumes that are accumulated during operation.
  5. The alternator is where the conversion from mechanical energy to electrical energy takes place. An alternator contains both stationary and moving parts that work hand-in-hand to produce the electromagnetic field and flow of electrons that creates electricity.
  6. The generator’s control panel basically controls every component of the generator operation from the startup to speed to outputs. Advanced and modern types of generators are capable of detecting when power goes out or dips and can turn on and shut down the machine automatically.
  7. Regulators help control the electrical voltage that is produced by the generator. It also helps to convert the electrical current from AC to DC, when necessary.
  8. Batteries may be needed to start up the generator. A battery charger ensures that the battery is charged up and ready to go. The battery charger is fully automatic and supplies the battery on the generator with a constant low-level of voltage.
  9. Lubrication ensures that the moving parts inside the generator are properly lubricated with engine oil. These parts need to be lubricated to guarantee a smooth operation and protect the generator from wear and tear.
  10. The body of the generator is called the main assembly/frame. It is the part that is visible to everyone—the structure that holds all the components of the machine in place.


When it comes to operating a generator, there are a lot of things you need to know if you care to understand how generators work.

If you need assistance with generator repairs and maintenance, contact Greg’s Small Engine.