How Do Generators Work? An Important Guide

If you own one, it’s probably bailed you out countless times, but have you ever wondered, “How do generators work?”

Imagine when the power goes out in your home or business because of extreme climatic events in your area. There’s nothing worse than navigating those stressful situations without electricity (or AC). Your generator can help keep you and your family as comfortable as possible in the face of deep freezes, heatwaves and hurricanes. That's true even if you can’t explain the difference between a watt and a volt.

Understanding how a generator works, however, can help you better understand the maintenance required to keep your backup power source reliable. And it’ll let you better address any issue that may arise.

This article will dive into the transformative technology behind generators. It will touch on the different parts inside your backup power source that keep it running. And it will explain how the power gets from your generator to your appliances in an efficient and safe way.

If you’ve ever wondered, “How do generators work?” read on, and we’ll explain it all.

How do generators work? The basics

Let’s start with the fundamentals. A generator literally generates electricity. Specifically, it takes mechanical energy,-- created by an object in motion and also known as kinetic energy -- and uses it to generate electric energy.

Why is this important? Well, usually you get your electricity from the electric grid, also called the power grid. The power grid is a network used to deliver individuals and families their electricity supply.

That network begins with energy production at a power station. Electricity might be produced by using water, oil, coal, natural gas, nuclear power, wind, or even the sun. In the case of a coal-fired power station, for example, coal is burned in a steam boiler to produce heat and, thus, steam. The steam moves a turbine. The turbine provides the mechanical energy that can be converted to electricity. How? It’s a process called electromagnetic induction, and we’ll get to that in just a bit.

First, how does that electricity get to your home? After the electricity is produced, a transformer can take the voltage of this electricity and increase it. As a result, more power can travel the long distance to far-off communities. When the electricity reaches those communities, another transformer can reduce the voltage, so it can be used in your home.

A series of transmission lines, electrical towers, and individual distribution lines provide a path for the electricity to reach us.

Electric grids are reliable. As we mentioned earlier, however, they sometimes fail. A hurricane, tornado, heatwave -- or one of many other extreme weather events -- can cause our power grid to fail.

What do we do then? Just wait in extreme heat, cold or a storm without electricity?

We wouldn’t advise it!

A mini power station for your home

An electric generator can avoid this uncomfortable situation. Backup power generators can be thought of as a mini power station for your home. 

Just as a power station does, it takes kinetic energy and turns it into electricity. That small electric current might not be able to power your entire home like the grid. But, depending on how big your generator is, it can power enough to keep you and your family in comfort.

However, that still leaves us with our big question. How does a generator convert a movement, or kinetic energy, into electricity? That process is called electromagnetic induction, and we’re going to learn about it now.

How do generators work? A generator's parts

English scientist Michael Faraday is widely considered one of the most influential scientists in history. Albert Einstein -- you might have heard of him -- kept a picture of Faraday on his wall. One of Faraday’s great achievements came in 1831,when he discovered electromagnetic induction. The process works using two main parts.

One of those components is a copper wire tightly wound around a piece of metal. Together, they are called the armature. The other piece is a magnet. 

Now, remember, a generator turns kinetic energy into electricity. We can do the same on a very basic level with just our armature and magnet. If the armature is moved back and forth across a magnet, for example, that motion is kinetic energy you’re creating. The motion -- as the armature moves between one pole of the magnet and the other -- induces electric energy.

That’s how you turn mechanical energy into electricity.

Fuel system

First, we need fuel to get that kinetic energy started. Different generators use different types of fuel. In past articles, we’ve discussed the pros and cons of various kinds of fuel, including gasoline, diesel, propane, natural gas and others. Some can even use multiple types. Determining the type that’s best for your home is one of the most important decisions you’ll make while designing your backup power system.

The main objective of your fuel system is to provide your engine with what it needs to create the kinetic energy for electromagnetic induction.

Your fuel system includes several features to accomplish this goal. We won’t mention them all here, but they’re each important.

One of the most essential parts is the connection from the fuel tank to the engine. This pipe is a supply line that allows fuel to travel from your storage tank to your engine.

Equally important is the fuel injector. It atomizes the fuel and sprays it into the engine’s combustion engine.


The engine creates the mechanical energy your generator will need for electromagnetic induction. 

Engines come in different sizes. The larger the engine, the more power it will be able to produce. Use AlltimePower’s free Backup Power Calculator to determine the electric capacity your home will require. We’ve also discussed generator size in past articles.

The atomized fuel powers the engine, allowing it to spin. Remember how earlier we mentioned that a coal-powered power plant produces steam that turns a turbine? This produces the kinetic energy needed for electromagnetic induction at the power plant. 

Your generator does something similar. The fuel allows your engine to spin, also producing the mechanical energy your generator will need to induce electricity.


Remember all that talk about magnets and armatures? When they move around each other, it induces electricity. Well, that same process happens inside the alternator of your generator. The engine creates a mechanical energy that your alternator will form into electrical energy.

The alternator is also known as the genhead, and it contains several moving or stationary pieces. These mirror the two parts from the example we gave to describe electromagnetic induction, earlier. It's important to remember there's a magnet, there's an electrical conductor wrapped in coils, and movement is used to induce electricity.

That’s what happens inside a generator. The stator is a stationary piece. It’s the piece with the electrical conductors wrapped in coils around iron ore.

The second ingredient is the armature, which is also known as the rotor. This is the moving part, meaning it provides the kinetic energy produced by the engine. It’s also a magnet. As the armature rotates around the stator, the magnet induces electricity from the conductors in the stator. Once again, this is electromagnetic induction.

We now have electricity, and that begins to move through the coils and out of your generator. 

There are many more components your generator needs to keep it running effectively. A voltage regulator controls your generator’s output voltage. The cooling and exhaust system assists in removing heat, so your generator can continue to operate. There’s a lubricating system that keeps the moving parts functioning, a battery charger to keep your generator’s battery charged, and even a control panel.

Again, this is only the tip of the iceberg. But if you understand how the main parts of your generator work, you’re off to a very good start.

How do generators work? From your generator to your home

How your newly created electricity gets from your generator to your home is determined by what kind of generator you have. A permanent standby generator, for example, is always connected to your home. It sits -- dormant, but waiting -- until traditional power from the electric grid is lost. As soon as the power goes out, your standby generator will kick on to provide power to your home, appliances, and AC.

But maybe you don’t have a standby generator. Maybe you have a portable generator instead. Rather than being switched on automatically, you’ll roll your portable generator out from the place it’s being stored. From there, you’ll connect it to your appliances via extension cords or less often by connecting the portable generator to your home's circuit panel via a transfer switch or a generator interlock kit.

Next steps

Now that you know how a generator works, our website can help you find the right sized generator for your needs.

Some shy away from buying a generator because they’re overwhelmed by a technology they don’t understand. But, as you can see, it’s nothing more than the simple principle converting mechanical energy into electrical energy. Taking advantage of that technology can help you and your family remain comfortable, even when an extreme weather event knocks out the power grid.

Next time someone asks, "How do generators work?" you'll be ready to answer.

Free Generator Estimate

Only takes 2-3 Minutes

Get Started