How Does a Portable Home Generator Work?

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Are you thinking about how a portable generator works but can’t find any suitable answers? Well, we want to say that this post is the most suitable option for getting a fulfilling answer to your query.


What Is a Portable Generator?

A portable generator is a device that comes with an engine, power outlets, a generator head, and a fuel source. The electricity delivered to the system is produced by the generator head using a certain type of fuel that includes diesel, liquid propane, or even natural gas depending on the construction of the unit.

The mechanical energy is supplied using a 4-cycle engine for powering the head of the generator with the help of a spinning shaft. The speed of the spin is controlled using a governor.

The power outlets on these units allow you to plug in extension cords, power tools, sump pump, or any other appliances you need power with your house generator during any kind of power outage.

How Does a Generator Work?

Generators convert mechanical energy from an external source into electrical energy as the output. It doesn’t CREATE the electrical energy. Instead, it uses the energy supplied to force the movement of electrical charges in the wires through the external electric circuit.

The main components of a generator include the engine, alternator, fuel system, voltage regulator, cooling and exhaust systems, lubrication system, battery charger, control panel, and its main assembly and frame.


The engine is the source of the input energy to the generator. The power output of the generator will depend on the size of its engine. Different types of fuel are also often used for generators, including diesel, gasoline, propane, and natural gas. Some hybrid generators can run on a combination of two fuels.


This is the part of the generator that produces the electrical output. There are stationary and moving parts that are encased in a housing. All of these parts work together to ensure movement between the magnetic and electric fields. This is what generates the electricity you need.

Fuel System

An average fuel tank for a generator can hold enough fuel to supply operation for approximately 6 to 8 hours.

Voltage Regulator

This converts the AC voltage to DC current. The DC current is then fed to windings in the stator. These winders are also known as the exciter windings.

Cooling and Exhaust System

As a generator experiences continued usage, many of its components begin to heat up. For this reason, the generator needs to have a cooling and ventilation system in place to help disperse some of that heat and prevent the device from overheating.

Lubrication System

Since generators have many moving components, lubrication is needed to ensure that these components continue to move smoothly and effortlessly. Oil is stored in a pump of a generator, and this is what provides the lubrication. You should check the oil after every 8 hours of operation.

Battery Charger

The start function of a generator is powered by a battery. The battery charger is responsible for keeping the battery charged and will not interfere with the normal functions of the generator.

Control Panel

This is the overall interface of the generator. This is where you will find the electrical outlets and controls. Different manufacturers will have different features here, including an electric start and shutdown, engine gauges, generator gauges, and phase selector switches.

Understanding Wattage, Amps, and Volts

There is a lot of confusion regarding these measurements. Our team is going to solve all those doubts by providing the right sort of information. The amount of power produced by the generator is calculated in the form of a watt.

If you see an increase in the watt, then there will be an increase in the other two units, i.e., amps and volts. The traditional formula for calculating power is watts= amps X volts. There are two major types of watts that we have mentioned below:

Running Watts

Running watts can be defined as the power that a generator can supply consistently for keeping the system running. If you can’t find the running watts on the generator, you can estimate it by using the equation above. Only a motor-driven device will require starting watts.

Starting Watts

Starting Watts can be called the additional power that holds by the generator for starting up heavy load appliances or a cluster of equipment.

If you want to ensure that your generator provides the maximum output with proper safety, then it is strongly suggested to place it in the outer area. The reason behind that is it makes sure your health doesn’t get affected with carbon monoxide emissions.

Difference Between Running and Startup Power

When you get a generator, it is because there are things in the home you want to power in the case of an outage. So, you want to check the running requirements of these appliances beforehand.

Larger appliances will require a much more substantial initial surge. This surge of power (startup power) is what is needed to kick start the power and get things going. You then have the running power, which is what is required to run the power for the appliance in a continuous usage mode.

What Size Generator Do I Need?

Most generators run in size between 1800-watts and all the way up to whole house generators that can produce more than 20,000 watts of power. Because of this variation, the prices will also differ, so it can sometimes be a challenge determining exactly what you need.

Just remember that the output of the portable generator you choose should be enough power to keep your household essentials like your water pump, some lights, a heater, and sometimes even a refrigerator going. So, if you are faced with a power outage, your portable generator can definitely come in handy.

Your portable generator can be connected to the circuit breaker panel of your home with a transfer switch or interlock device. The transfer switch on the generator is the electrical switch that switches the load between two sources.

An automatic transfer switch is usually installed where a backup power generator is located. This provides temporary electrical power if the utility source ends up failing.

Connecting the generator to the main breaker also allows your portable generator to power the entire circuit instead of having to plug in all your devices and extension cords separately.


It is important to have the necessary education before you begin to operate the portable generator. Get a complete understanding of the risks to ensure that you can keep your family safe.

We strongly believe that this post about “how to portable generators work” has helped in solving your queries. If you have a question or suggestion, then write to us in the comment section.

Eric Arnow