How to Build a Generator

Almost everything in the modern world is dependent on electrical power to some extent. In virtually all situations, that isn’t a problem at all. But sometimes, the AC power that your local power grid usually provides stops flowing. Maybe there’s a temporary outage in the electric current produced by your power grid. Or you’re in an area where the power grid doesn’t operate in the first place, such as on a hiking or camping trip. Either way, you need power, and you can’t get it. Some of your appliances might work with a standard battery, but batteries run out.

So even if you’re well stocked up on portable equipment that does not require direct AC electrical power, you’ll only be able to use it for a limited time before the battery runs out of charge.

When that happens, you’ll need another source of AC power (emergency power) for your electrical appliances and equipment. That is when a power generator comes in handy. After all, you can’t check your email with no power. You can’t charge a small battery without power either!

Gasoline-powered generators provide all the electrical power you need for charging batteries or powering appliances. But, sometimes, you don’t have a generator available. In this case, you might want to know how to build a generator at home. This process is complex and involved and not just something you can make up as you go along.

Here at Best of Machinery, we’ve got you covered. We’ve put together a guide on how to build DIY generators safely. Below, you’ll find an easy-to-follow step-by-step guide and a list of all the pieces and components you may need to use when building a generator.

You won’t need to search for lists of strange parts and incomprehensible explanations to make a generator at home! No matter what your questions may be, or how little DIY experience you may have, simply read on to find out everything you need to know about building a generator. Even a small generator will see you through most applications.

How Can I Generate my own Electricity?

Generating your own electricity will ensure you’re never lost during a power outage. Charge your electronic devices and appliances, including your hairdryer, space heater, power drill, and more!

There are a few different ways that you can generate power. One of the best energy source options is solar panels. Of course, solar power isn’t the cheapest to get set up, but solar panels are a great way to generate power for your home without worrying about fuel supplies or the environmental impact of generators.

Solar panels can be very expensive, though. So if you need to produce a current and can’t afford to get solar panels set up, you could try to make a generator from parts and generate electrical energy that way.

This option requires more effort and has a much greater environmental impact than using solar panels for power generation. Still, it’s much more affordable in the short term. However, solar panels can save you more in the long run, once you’ve used them for a long time! But there is a very high one-off cost for setup, so not everyone can afford them.

You could also power your devices and a few light bulbs with a bicycle generator! A bike generator is another environmentally-friendly option to power different devices. You’re using human energy to create power – how cool is that?

However, this may not be sustainable in the long run, as a bike generator wouldn’t be able to power your entire home. However, with technology always improving, that’s not to say a bike generator wouldn’t be able to power whole streets in the future. Also, when you stop pedalling and end up with a stationary bicycle, you’ll stop producing power.

You could also use a power inverter in emergencies, which takes energy from a car battery (or something similar) and uses it to power appliances. Although a power inverter is good in emergency situations, it’s not a sustainable option and won’t provide enough energy to power your home.

How to Build a Generator

Building your own generator at home and using pieces from other power tools, such as a motor, is a relatively easy task. With a bit of time, patience, and work, you’ll soon get back to checking your email in no time!

Let us walk through everything and show you how to make your own generator. We’ll cover all the pieces you need, all of the tools you’ll have to use, and a few general rules to keep in mind. In the end, you’ll have your very own small generator for home use.

Step 1: Find an Engine

The most important part of a generator is the engine. The engine size needed for DIY generators varies. This is because the size of generators and the power they need to output also varies. Larger generators for more energy will need a larger and more powerful engine, while smaller, more portable generators will want a small engine with limited power output.

Today, we’ll show you how to make a small, compact generator that outputs enough power for most standard home use. For a generator like this, you’ll want to use an engine of around 5 to 10 horsepower, with 3,600 RPM.

In general, a motor like this will be about the size of a standard lawn mower engine. You should be able to browse lawn mower engines at your regular lawn equipment store, power equipment store, or industrial supplier outlet.

A treadmill motor is also a popular choice for DIY generators. However, they’re better for small wind generators.

Before you purchase a gas engine for your home generator setup, it might be worth checking to see if you have any old garden equipment that you no longer use. Many people have old unused garden machinery gathering dust in a corner somewhere. Repurposing an unused motor and motor shaft is a great way to save a respectable amount of money when trying to build your own generator at home.

Step 2: Choose your AC Generator Head

The AC generator head is an important component when making a generator. You might need to search around a bit to find one, but if you have access to a good industrial supply outlet or two, you should be able to get hold of one easily.

This component uses a magnet inside its body to create an electrical current. The external engine spins the shaft-mounted magnet, which creates the all-important current.

In most cases, you’ll need one with an output of somewhere between 2,500 and 5000 watts. In general, a generator can produce about 750 watts of current per horsepower of input. Use the manufacturer’s specification to match the AC generator head to your engine size.

Step 3: Choose a 12 Volt DC Alternator

You’ll want to use a 12 volt DC alternator as one of the main pieces of your generator. This device will create an output voltage of 12 volts when the external engine is used to drive the generator shaft.

Make sure you have chosen an alternator with a built-in voltage regulator. If your alternator doesn’t include a regulator, you’ll need to search for another one, as this is a very important feature. You would want a standard 500-watt alternator to produce the correct voltage in most cases.

You should be able to get hold of a DC alternator with a built-in DC voltage regulator from any car and motor parts supplier. The alternator is an important component because it converts the generator’s DC (Direct Current) into AC (Alternating Current), the type of current needed by most domestic appliances.

The regulator keeps the output constant, preventing unexpected dips from stopping your appliances mid-flow. If you don’t have a regulator, then any fluctuations in the voltage produced by your generator can cause spikes and crashes in the output voltage, which can be very problematic for any devices connected to the other end!

Step 4: Build a Mounting Plate

You’ll need a sturdy mounting plate to set up all the components of your generator. This can be made from any strong material, as long as it’s something that would survive the vibrations and heat produced by the engine when it’s operational. You will have to add the main power components of your generator to this: the engine, the generator head, and the alternator with a voltage regulator.

Look at the manufacturer data for every one of these components, including the motor. Find the relevant information on what size of mounting hole you’ll need and where you may have to position these holes on the mounting plate. Then, using the manufacturer data as a guide, add these three main components to the mounting plate.

Make sure that you arrange them so that their shafts are parallel and all pointing the same way. This way, the shaft attachment areas for drive pulleys (also known as a direct drive) all line up and face the same way.

Step 5: Set up your Pulleys

An additional engine pulley (or direct drive) is used to drive the pre-installed pulleys of the generator head and the alternator. You will have to mount this onto the engine shaft to use it properly. Make sure you find the right pulley size for the generator head and the alternator. They should both run at the speed indicated on the manufacturer data list.

In most cases, the engine pulley size will be between 5 and 10 inches in length. Pulleys are easy to find at most industrial supply stores that sell other engine and motor components.

Step 6: Run the Belts to Test Them

Depending on the precise design of your generator and what size components you’re using, you might need two pulleys and belts, one for each of the generator heads and the voltage regulator alternator component. Alternatively, you might be able to work with only one pulley and one belt system. Slot the drive belt over the pulleys and ensure that it is taut.

It might be easier to get everything taut if you slot the mounting holes on the side of the engine. Here, you can adjust things more easily. Using a V belt is generally better than a standard belt, as these slip less when used.

Step 7: Set up the Gasoline Tank

Place your gasoline tank on the mounting plate. Screw it firmly into place, ensuring that there are no other components in the way. Then, fill up the gasoline tank using an appropriately-sized funnel, and connect the fuel feed lines securely to the engine.

Step 8: Run your Generator!

Once you’re sure that every component of your generator is firmly attached to the mounting plate, you should be ready to go. The engine is the most important piece here, as it would cause the most problems if not attached properly. Using a large screwdriver, ensure that all your mounting screws are tightly fixed in place and flush with the side of the mounting plate.

Once everything is as tightly attached as possible, you’re ready to run your generator and send power to your appliances!

Can I Use an Electric Motor as a Generator?

You can use almost every type of motor to generate electricity, but it will require a bit of rewiring before being used as a generator. While a gasoline engine is designed to produce power as standard, an electric motor is not.

Most modern AC induction motors (check the side of your motor to determine what type it is) work well as a generator to produce power if you rewire them, and you don’t need any specialist equipment or skills for this.

Let’s go through how to use an electric motor as a generator step by step.

Step 1: Inspect your motor for Information

Like a gasoline engine, there should be a nameplate on the side of your motor that offers information about its voltage, phase, full load current, and speed. The full load current refers to the maximum amperage of power that it can produce as a generator. (You may want to get an amp meter, too!) The voltage refers to the rough power voltage produced when you use it as a generator.

If you plan to use it as a generator, you’ll have to turn it at about 5 to 10 percent above the listed running speed to produce electricity.

Step 2: Prepare your Wires

Cut four pieces of wire. Each one should be about 2 feet in length. Strip about half an inch of insulation from the end of each of these wires. Then, insert the end of a wire into the crimp of a spade wire terminal and crimp it firmly into place. Then do this again with a second wire. Push the spade connectors into place on the capacitor terminals.

Step 3: Attach the Wires to the Terminals

Using a screwdriver, loosen a terminal on each side of the container. Wrap a wire around each of the terminals in a clockwise direction, and tighten up the terminals again. Feed the wires out of the cable hole at the rear of the receptacle wiring box. Mount the receptacle to the box just like you would mount an engine to a generator mounting board.

Then, place a wire end from the capacitor, a wire end from the receptacle, and a motor wire end together in the same space. Use a wire nut to hold them tightly together. Repeat this for the other motor, receptacle, and capacitor wires.

Step 4: Getting Started

You’ll need a gasoline engine or another source of power to kick your motor generator into action. Attach your engine to your motor-generator and start it up. You’ll need it to run somewhere between 5 and 10 percent above its official-rated speed. Leave it running attached to the engine for a few minutes.

Once you’ve started up your motor using a separate engine, you’ll need to test the AC voltage. Set a multimeter (or volt meter) to test 250 volts AC, and insert the multimeter probe into the receptacle slots. The multimeter should display an output voltage somewhere between 110 and 135. If this is the number you’re getting, you are ready to go!

With the engine turning the motor, you should now be able to connect the motor-generator up to other electrical appliances, such as lights, and send power to them to use them safely!

If you are not Getting any Electricity from your Motor-Generator:

Allow your motor-generator to stop before you attempt any troubleshooting, even if there appears to be no current generated. It’s important to be careful and safe when dealing with homemade electric generators! Discharge the capacitor component by touching a screwdriver to a terminal and then the other. Make sure to maintain contact with the first terminal.

Then, it’s time to disconnect the capacitor wires. Remove the wires. Touch each wire to the 12-volt battery terminals of your motor-generator for somewhere between 5 and 10 seconds each. Then, replace the terminals onto the capacitor element.

Once you’ve reattached everything and checked to ensure nothing is loose, you’re ready to start your motor generator again and see if it works. Follow the last couple of steps listed above to test for electrical current output. If it’s still not generating current, there must be another problem with your motor-generator setup.

Potentially, there could be a damaged winding element or a capacitor that’s not functioning properly. Unfortunately, you’ll have to replace each component in sequence to find out which is not working as required.

Final Thoughts

As long as you have all of the components required and take the time to complete every step carefully, building a generator at home is not a particularly difficult task. It’s a complex and involved project, but you can buy all the elements required from auto supply stores and engineering shops. As long as you have access to the appropriate retailers, you can build DIY generators at home without much difficulty! It may take a while, but the results should be well worth your time and effort.

Take your time, do your research, and follow our guide above carefully. As long as you’re patient, you’ll end up with a great independent power source without needing to break the bank! No more worrying about power outages and unstable, unreliable local electrical grids!