A generator is a reliable tool whenever you need electricity during power outages. While generators are a lifesaver during emergencies, you may want to know how they work — specifically, whether they all use electromagnets.
Not all generators use electromagnets, though they often rely on magnetism to generate electricity. Some generators use a permanent magnet made from iron, nickel, and cobalt to create a magnetic field, while those with electromagnets rely on electric current for the same.
This post will explore in-depth how generators work to produce energy, what electromagnets are and how they’re used in generators, the benefits and drawbacks of using electromagnets in generators, and the difference between permanent magnets and electromagnets. Let’s get started!
How Generators Work To Create Energy
A generator converts mechanical energy into electrical energy through electromagnetic induction. During this process, a conductor is moved through a magnetic field, which causes electrons to flow and create an electric current (source).
Inside the generator is a copper conductor coil with an armature (a metal core) turned by an external power source like a gasoline engine. As the armature turns, it creates a magnetic field that interacts with the field of the permanent magnet or electromagnet.
This interaction between the two fields causes a flow of electrons (electric current) in the conductor coil. The electric current is then sent to an external circuit where it can power electrical devices such as:
What Is an Electromagnet, and How Does It Work in a Generator?
An electromagnet is a temporary magnet that uses electricity to create a magnetic field. It’s made of a coil of wire wrapped around a ferromagnetic material like an iron core (source).
When electricity flows through the wire, it creates a magnetic field concentrated on the iron core. To maintain the magnetic field, electricity must continuously flow through the wire. Turning off the current will cause the magnetic field to disappear.
You can increase or decrease the strength of the magnetic field by changing the amount of current flowing through the wire. Reversing the flow of current will also change the direction of the magnetic field.
Electromagnets are often used in generators because they can instantly create a magnetic field that agitates the electrons in the conductor coil, which in turn causes them to flow freely. This flow of electrons produces an electric current sent to an external circuit to power electrical devices.
How an Electromagnet Differs From a Permanent Magnet
Not all generators rely on electromagnets. Some of them use permanent magnets to create the magnetic field. A permanent magnet is a piece of material (usually made from iron, nickel, or cobalt) that creates its own magnetic field.
The magnetic field is created by the orientation of the atoms within the material (source).
The main difference between an electromagnet and a permanent magnet is that a permanent magnet will retain its magnetic field even when the current is turned off. On the other hand, an electromagnet will only create a magnetic field when an electric current flows through the wire.
Permanent magnets are permanently magnetized and will never lose their magnetism, whereas electromagnets are only temporary magnets, creating a magnetic field only when an electric current flows through the wire.
Additionally, the strength of the magnetic field in a permanent magnet is constant, while in an electromagnet, it can be increased or decreased by changing the amount of current flowing through the wire.
This makes electromagnets more versatile than permanent magnets, as you can adjust the strength of the magnetic field depending on your needs.
Benefits of Using Electromagnets in Generators
Modern generators rely heavily on electromagnets for energy production due to the many benefits they offer. These include:
Unlike permanent magnets, electromagnets can be turned on and off instantly. This means they can be used more efficiently as they’re only active when needed. Therefore, generators using electromagnets are ideal for use in power plants where electricity demands can fluctuate rapidly.
As I mentioned, the strength of the magnetic field can be easily controlled by changing the amount of current flowing through the wire. This gives you more control over the generator and allows you to fine-tune the amount of electricity being produced depending on your needs.
Inexpensive and Easy To Build
Compared to generators using permanent magnets, those with electromagnets are much less expensive and easier to build. This is because permanent magnets are made from rare and expensive materials like iron, nickel, and cobalt. On the other hand, electromagnets are made from easily accessible materials like copper wire and iron cores.
Drawbacks of Using Electromagnets in Generators
Although electromagnets offer many benefits, there are also some drawbacks to using them in generators. These include:
Requiring a Continuous Electric Current
Since electromagnets rely on an electric current to create a magnetic field, they need a continuous electricity supply to function. If there’s an interruption in the power supply, the magnetic field will also disappear, causing the generator to stop working. This can be costly and inconvenient, especially when a constant supply of electricity is crucial.
Prone to Overheating
Another downside of using electromagnets is that they can overheat and become damaged if the electric current flowing through them is too high. The wires in the electromagnet can start to melt, and the iron core can become magnetically saturated, leading to a decrease in the strength of the magnetic field.
As a result, the generator will become less efficient and may eventually stop working altogether, costing you money in expensive repairs.
Can Interfere With Other Electronics
Because they rely on electromagnetic fields to create electricity, generators with electromagnets can interfere with other electronic devices. The electromagnetic fields generated by the generator can disrupt the signals of nearby electronics, causing them to malfunction.
They can also be dangerous to people using sensitive medical equipment like pacemakers, as the electrical signals from the generator can disrupt their functioning.
Although generators rely on magnetism to produce electricity, not all of them use electromagnets. Some generators, like those used in wind turbines, use permanent magnets instead.
However, most modern generators use electromagnets as they’re more efficient and offer more control over the amount of electricity being produced. While electromagnets have some drawbacks, the benefits outweigh the negatives, making them the preferred choice for most applications.