How Can A Car Alternator Be Utilized To Generate Electricity? (Easy Steps to Follow!)

Last Updated on January 15, 2023 by Leepu Da Maxim

You can generate electricity from a car alternator by harnessing the power from the engine’s rotation to turn a rotor inside the alternator. You can also generate electricity from a car alternator when it works in conjunction with an internal combustion engine.

Key Takeaways

  • The two main functions of a car alternator are generating electricity and maintaining battery voltage
  • A car alternator converts the alternating current (AC) to direct current (DC) using a rectifier
  • You can store the converted electricity in a battery or can directly use it to power electrical devices
  • You should keep in mind that the car alternator is specially designed to power the car’s electrical systems so it is not wiser to use it as a standalone power source

What is a Car Alternator?

The car alternator is a type of generator that converts the mechanical energy of rotating pulleys into electric power.

This device has two main functions: generating electricity and maintaining battery voltage. The first function is done by the exciter coil, which generates a magnetic field from one end to the other, while current is passed through it. This creates an alternating electrical voltage inside the body of the alternator. The second function is done by a pair of diodes, which directs the current to charge or discharge either the car battery or an external electrical load.

In this way, the alternator will have the ability to generate electrical power off the grid. Also, the alternator will have the possibility to charge non-vehicle batteries.

How Can A Car Alternator Be Utilized To Generate Electricity

How Do The Car Alternator Generate Electricity?

The car alternator generates electricity through a process called electromagnetic induction. The process starts with the engine turning a pulley shaft, which in turn spins the alternator’s rotor. As this rotor spins, it builds up a magnetic field that induces an alternating current flow in the generator’s windings, which results in electricity being generated.

The rotor, which is the spinning shaft on top of the alternator, has electro-magnets that interact with the electro-magnet in the alternator. As they spin, they generate AC voltage in a form of a rotating magnetic field and hence generate electricity for the car’s battery.

Tips For Using A Car Alternator To Generate Electricity

Having A Car AlternatorVintage car alternators offer excellent designs for generating electrical power
Battery Type
In any case, it is necessary to have a 12-volt battery with a good lifespan
Type Of Use
It is possible to use an alternator as a backup power source or as a free power generator
External Regulator
An external regulator may be necessary for some alternators with more than 3 terminals
Ecological Source It is recommended to choose an ecological source according to each geographical area to generate free electricity 

Step by step on Generating Electricity Using Alternator

On many occasions, users wish to avoid using the conventional electricity network. Instead, there are many ways to generate electricity off the grid. In this case, the alternator can be a key part of being able to generate energy from renewable sources. Therefore, users who have an old car that they no longer use can extract the alternator for this task.

Once the alternator begins to generate electricity, no additional work will be necessary. Below, we can mention the necessary steps to be able to use an alternator to generate electricity.

This procedure is much more efficient when people have one or more rechargeable batteries. Here, the energy generated is stored so that it can be used at another time.

1. Choosing A Good Alternator

One of the most important steps in this procedure is the choice of the alternator. Of course, vehicle alternators are not all the same and offer different capacities. In general, people recommend a junkyard to find an alternator with an old design. For the task of generating electricity off the grid, these alternators are usually very efficient.

In turn, the vast majority of alternators include certain components that can help with this task. Here, we are talking about internal regulators controlling the rate of charge.

Otherwise, irregular electricity generation could generate serious damage to the different components of this alternative electrical system. The rechargeable batteries you want to use could be affected by a malfunction of the alternator. Additionally, choosing the right alternator provides the possibility of establishing an efficient installation.

Besides, the connection at the time of generating electrical energy will be stable and will not present major inconveniences for any of the components used. In other words, choosing a good alternator is important, since it is the main part used to generate electrical energy in an alternative way.

2. Connecting The Alternator

A 12-volt battery is required for the installation and connection procedure. Of course, the vast majority of large batteries have this amount of voltage. Also, it is really important to check that the battery has the right voltage to establish an efficient connection. Otherwise, the components will be somewhat incompatible with each other.

Once you connect the 12-volt battery to the alternator, you can get a power system with a good level of stability. Here, it should be considered that the positive terminal of the battery should be connected to the larger terminal of the alternator.

In turn, the frame or housing of the alternator is what should be connected to the negative terminal of the battery. Connections made in reverse simply do not work. Also, depending on the design of each alternator, two or three smaller terminals may be left unused. Here, we can mention some important tips when it comes to some alternators in particular.

The regulator built-in means that the design has two terminals. Here, one of them should be connected to the positive terminal of the battery while the other should be connected to the small terminal.

To establish this particular connection, it is advisable to have some kind of switch. So, the connection here is made to a positive voltage source to avoid inconveniences in the electrical system. The regulator can be energized by this power circuit. In turn, you will notice efficient control over the output voltage of the alternator.

Approximately, we can mention that the output voltage of the alternator could be between a maximum of 14 to 14.7 volts. On the other hand, you will need an external regulator if you have an alternator with a three-terminal design. In turn, it is necessary to run the wiring from the alternator to the regulator.

Along with this, you should not forget the wiring from the alternator to the positive of the battery. After that, you must turn on the positive voltage to go to the regulator instead of the alternator.

It is possible to use the alternator as a backup in case of a regular system failure. In other words, the alternator can be used as a backup power source. However, this requires a small gasoline engine. A lawnmower engine will be more than sufficient. 

3. Screwing On The Alternator

Remember that it is important to screw in the alternator correctly to continue and complete this procedure for creating the alternative electrical system. The bolting must be done to the platform and a pulley must be placed on the output shaft of the gas engine.

This component is usually highly recommended and is used to drive the alternator through a belt. Once all this is properly located you can continue and start this alternative energy system.

What is a Car Alternator.jpg

4. Use Environmentally Friendly Sources

Finally, you must choose an ecological source to be able to generate alternative energy off the grid. In this way, you will have the possibility of generating free and environmentally friendly electricity.

One of the most evident possibilities is to use a solar panel to be able to take advantage of solar energy. However, this could increase the budget of each person considerably. 

There are also many solar panels on the market today with an increasingly accessible cost. However, this is not the only possibility since you could also take advantage of wind energy to generate your energy at home.

In this case, you will be able to generate electric energy using your alternator in the way we have mentioned. Here, you could choose to connect this system to a pole and mount a fan-type blade. In the same way, placing a propeller on the shaft can also be an excellent alternative.

In other words, here it is a matter of having some implement that allows taking advantage of the kinetic energy of the wind. So, in the presence of wind, your energy system will have the possibility of generating energy for free.

A third alternative is to take advantage of the energy that a stream or a body of water can offer. Here, the water current can do an excellent job if you mount a paddle wheel on the alternator. However, you should consider properly protecting the alternator from water or large amounts of spray. Of course, the alternator cannot be immersed in the water here either.

Once you have chosen the most convenient ecological source for you, you will have the possibility to generate electricity. The amount of electricity generated depends on the energy system you have created with your alternator. Beyond that, it is still a high-efficiency possibility to allow you to save some conventional electric energy. 

How Much Electricity Does A Car Alternator Produce?

Depending on the power source, a single-car alternator can produce up to 2500 watts. Anyway, the classification of each alternator is what allows us to determine exactly the amount of electrical energy that can be produced by an alternator.

That is why it is necessary to consider the specifications of each alternator before starting to produce electrical energy. In particular, an alternator can provide an ampere output starting at 40 amperes and can go up to 120 amperes. In other cases, high-amperage alternators are capable of producing 300 amps. 

Is An Alternator Charged All The Time?

In principle, it is necessary to consider that the battery energy alone is only good for the initial spark for starting the vehicle. In turn, the accumulated battery energy serves to drive a car on the road for a distance of only a few miles. That’s why an alternator is built-in when using any type of vehicle.

The alternator in a car is always responsible for continuously and stably charging the car battery. So, the alternator takes advantage of the kinetic energy that a moving car is producing. In the same way, the alternator also allows the car to continue to run while all of the vehicle’s electronics are being used. 

Can a car alternator be used as a generator?

The answer is an unequivocal no. A car alternator is a device that generates power from the engine when it is turned. It has nothing to do with producing energy from an external source; a car alternator cannot produce voltage or current to power anything outside of a running vehicle.

A car’s engine produces AC electricity, which must be converted into DC power before it can be used for other purposes. An alternator does this conversion under normal circumstances – converting AC into DC and sending it out to components such as headlights, taillights, and radios – but not much else.