What Is a Genset?

When you start exploring backup power options for your business, home, or worksite, you’ll likely see the term “genset.” What exactly is a genset? And what is it used for?

In a nutshell, “genset” is short for “generator set.” It’s often used interchangeably with the more familiar term, “generator.” It is a portable power source that uses a motor to generate electricity.

What is a genset used for?

Modern society can’t run without electricity. From Wi-Fi and communications to lighting and climate control, businesses and homes require a steady stream of power to function. 

Generator sets can add an extra layer of security in the event of brownouts or power outages. Standby generators can keep critical systems running at medical facilities, businesses, and homes in case utility power gets knocked out. 

Gensets also can provide a self-contained power supply in remote places off the power grid. These include construction sites, campsites, rural areas, and even mines deep underground. They enable people to harness power to build, explore, or live off the beaten path.

There are different types of electric generators. All have similar components, require some type of fuel, and are set in a base frame. But there are some key differences, too.

How does a genset work?

Electrical generators work in a similar way that cars do. They have a “prime mover” (engine) and an alternator. 

The engine converts a fuel such as gasoline, diesel, biogas, or natural gas (chemical energy) into mechanical energy.

The mechanical energy spins the alternator rotor to create electrical energy.

Alternators have two parts: a rotor and a stator. When the rotor spins, a magnetic field between the rotor and stator creates voltage (electromagnetic induction).

When the voltage on the stator connects to a load, it creates a stable electrical current.

Many homes and businesses find using gensets to be invaluable because when power is produced, it can immediately be used. Gensets effectively put an end to any disruptions due to power loss.

AC vs. DC gensets: What is the difference?

All generators use electromagnetic induction, but different setups can produce two different kinds of electrical energy — alternating current (AC) or direct current (DC). 

The overwhelming majority of gensets are the AC type, but it’s worth knowing the difference. 

As its name implies, alternating current changes direction. It oscillates back and forth dozens of times a second. AC electricity can travel at a high voltage, making it useful for long-distance delivery on the electric grid. A transformer “steps down” voltage for smaller-scale use. AC generators are used to run small motors, household appliances, computers, and office equipment. 

Direct current flows in a single direction at a lower voltage. It stays consistent from the generator to the final destination. DC generators power large-scale electric motors (such as subway systems), banks of batteries and solar cells, and LED lights.

What are the components of a genset?

Generator sets typically have these components:

Engine/motor. The primary genset component, it runs on fuel. Good engines are built strong enough to meet demand and function in adverse conditions (i.e., bad weather).

Alternator. This component converts mechanical energy into electricity; without it, there is no power.

Control panel. This acts as the “brain” of the genset, controlling and regulating all the other components.

Fuel system. This component consists of the storage tanks and hoses that send fuel to the engine.

Voltage regulator. This controls the amount of voltage the genset produces and converts an A/C current to a D/C current.

Base frame/housing. The base frame supports the generator and holds the components together. It also serves as an anti-vibration and grounding system, and may or may not house the fuel tank. It may be set upon wheels to make it portable.

Pull-cord mechanism or battery.  An initial spark is needed to start a portable generator’s combustion process. This usually happens either through a pull cord mechanism (like a lawnmower) or a starter motor powered by a DC battery. 

Manual or automatic transfer switch. The transfer switch directs power between the main source (utility power) and the auxiliary one (the generator). This keeps the electricity flow consistent and prevents dangerous disruptions.

Baffle box or enclosure. Often made of stainless steel, this container reduces noise, prevents corrosion, and facilitates airflow to cool the engine.

Generators don’t require intensive maintenance, but it’s important to understand their internal mechanisms. This way, you can perform preventative and general maintenance as needed, along with knowing how to order replacement parts.

What are the types of gensets?

Generators come in different sizes and can use different fuel sources. The following are the different generator fuel systems, including pros and cons of each.

Gasoline generators

Gasoline generators are the most popular option because gasoline is readily available. Gas-operated gensets also are low on the price scale, and they’re extremely portable. 

However, usage time for a gas genset can be short-lived and fuel inefficient. Gasoline stays viable in storage for about a year. But it’s also highly flammable, which could create a hazard in certain environments. 

Diesel generators

Diesel engines are more powerful than gasoline engines. Diesel fuel is also less flammable, and availability of it is pretty widespread. With proper maintenance, diesel gensets can last a long time. 

Major drawbacks are that diesel fuel is only good for about two years, and extensive use gets expensive. Diesel engines also create heavy emissions.

Biodiesel generators

Biodiesel fuel is a mixture of diesel and other biological sources, like animal fat or vegetable oil. Since it burns with lower petroleum emissions, it’s more environmentally friendly, creating less waste and a smaller fossil fuel footprint. 

A big drawback, though, is the noise levels associated with biodiesel engines.

Low-emissions options

Generators can also be run with low-emissions options, including natural gas, propane, or solar energy.

Natural gas is widely available and affordable, and it can run right from shale reserves, which means no refills. However, the big disadvantage is that a natural gas generator is not easily portable and is expensive to install.  

Propane burns cleanly and has a long shelf life but also is extremely flammable. Installation costs are higher, and these generators burn three times as much fuel as ones that run on diesel.

Solar generators are charged by the sun, so the fossil fuel footprint is nonexistent, and operation is simple. The drawback here is the limited energy supply. Also, the charge time is slow; if not enough charge is stored, an erratic fuel supply could be disruptive.

Small household backup generators typically use gasoline, but larger industrial generators generally run on diesel or natural gas.

Genset sizes and uses

Generators have a variety of power outputs and engine speeds. They can stand alone or be connected to buildings. Some portable generators have wheels or are mounted on trailers so they can be towed from one location to another. 

When choosing a genset, you’ll want to examine features such as power generation, fuel efficiency, reliability, and robust construction. 

Understanding electrical power output is helpful, too: Output is measured in watts or kilowatts. Larger generators can produce more electricity but have higher fuel consumption; however, smaller generators may not produce the power you need.

A solid grasp of your power requirements is key to helping you choose a quality genset.

Benefits of gensets

If your home or business is served by aging power plants or lines, then you’re familiar with disruptions. It’s the same if you live or work in a region prone to extreme weather events like hurricanes or blizzards. 

Losing power means you’re effectively shut down. For businesses, any interruptions or downtime can lead to major financial losses. 

Consequently, there are numerous benefits associated with using a genset.

Can be used as a primary or backup power source.

Serves as the main source of power for construction projects or remote operations. 

Operates as an emergency power source in the event of an unexpected grid power outage.

Provides protection against brownouts, which can be disruptive.

Produces savings for areas where peak grid demand is high — and, as a result, costly.

Emergency power generators provide reliable power to avert financial losses and security breaches. They can even prevent loss of life in hospitals and nursing homes. Most businesses rely on gensets to ease the negative impacts of a power outage. This helps them keep working, even in difficult times.

Having a genset ready in the event of a power disruption can be a lifesaver, sometimes literally. And even in situations that are not quite life-or-death, a genset can ensure smooth operations without interruption.