A generator makes it convenient to safely generate power when the grid goes down due to either natural or man-made causes [1]. It’s a backup power source that produces energy by converting rotating mechanical energy into electrical power, a process that is called electromagnetic induction. A generator engine commonly runs on diesel, gasoline or propane. This engine is used to turn an alternator that produces an alternating electrical current (AC) [2]. AC is the normal household electricity or current flowing in power lines supplied by a utility company. To run a generator safely, it should never be done in an enclosed space, and the exhaust should be directed away from home.

The three main types of a generator are portable, standby and inverter [3]. A portable generator uses a combustion engine to conduct electricity, and it can be plugged into electrical appliances or tools using its sockets. A governor is also used to control its engine’s speed, and the engine runs at 3600 rpm to provide the standard 60 Hz current. Additionally, this type can help run television and a refrigerator and be used in remote sites.

Standby generators are stationary units with two main components: a standby generator and an automatic transfer switch. They work through an automatic transfer panel that is designed to power devices automatically a few seconds after detecting a power outage. This type of generator can deliver permanent power protection, which makes it good for use in safety systems for elevators, medical and life support equipment and standby lighting.

Nowadays, the type of generator that’s popularly used to power mobile restaurants, mobile service providers and even offices, campsites and home appliances during power outages is the inverter generator. How does an inverter generator differ from the other types of generator? This guide will explain what it is, how it works and what is its advantages and disadvantages.

What is an inverter generator?

An inverter generator is a generator that has a built-in inverter. It combines the principles of electromagnetic induction and power inverter. The latter is an electronic method of producing AC from direct current (DC). A power inverter draws power from a power source, such as a car battery, and utilises an electronic circuit to ‘invert’ the DC into AC. The process results in an unvarying electrical signal [2].

How does an inverter generator work?

Simply, an inverter generator undergoes three phases to produce electricity. First, it outputs AC, then converts it to DC and finally inverts it to AC. It uses advanced electronic circuitry to work like this [3].

An inverter generator generates an AC that varies in frequency with the engine speed. A higher-engine speed results in a higher frequency, which translates to more current being generated. On the contrary, a lower-engine speed means less current. The variable-frequency current is rectified into DC current [2]. 

So how does an inverter generator differ from a conventional generator and which is better between the two? The main difference between these types is the mechanical components involved in each, which then affect how they run and function. These differences can be better explained by the advantages and disadvantages of an inverter generator, which are also presented in this article.

A conventional generator has a fixed engine speed. It maintains that speed to produce electricity. Meanwhile, an inverter generator varies its speed to produce the required power. This is what makes an inverter generator efficient when used. This generator also maintains a constant flowing of current to an appliance, and its AC can be set to any voltage and frequency when used with proper equipment [3].

With regard to which type of generator is better, it will be dictated by the specific generator needs a person has. It will depend on the appliance that needs to be powered and the budget allocated for it. Sometimes fuel efficiency is not what’s needed to make a generator better but its noise level. Also, it may not be the one that can produce a large amount of power but one that will fit your car.

Advantages of an inverter generator

Although an inverter generator is more expensive, it offers many advantages. Here are several reasons why someone should choose an inverter generator over the regular one.

  • Quiet operation

The noise level is how an inverter generator mainly differs from the conventional generator, which tends to be noisy when in use. Given that an inverter generator can adjust the amount of power produced using microprocessors, it can regulate its power output, depending on the applied load. This makes this generator type quieter than the others when working [4]. With this feature, an inverter generator is ideal for use in food trucks, camping and noise-sensitive construction environments.

  1. Higher fuel efficiency

The capacity of an inverter generator to automatically adjust its engine speed to produce only the power needed for the application makes it fuel-efficient. A traditional generator constantly runs at 3600 rpm to produce a 60 Hz cycle of electricity, while an inverter runs by varying its speed to produce the needed power. Without the need to run at a constant speed, an inverter generator reduces fuel consumption by 20%-40% [56].

  • High-quality power output

Most devices now are sensitive to the quality of electricity used. If they are used by utilising an unclean power source, they may get damaged or end up malfunctioning. It’s a good reason why an inverter generator should be better used if there’s a power outage.

Inverter generators produce consistent and reliable power that doesn’t rely on engine speed. This power is considerably ‘cleaner’ than the one produced by conventional generators; it’s almost of the same quality as the electricity supplied by the utility company [4].

The inverter’s electronics technology gives a cleaner power because of the following reasons: the inverter generators’ initial AC has a high frequency, which provides more electricity, and its inversion ability. As a result, inverter generators have more control over AC frequency [7].

  • Smaller, lighter size

Many inverter generators are relatively small compared with conventional ones. Their parts from the generator and the engine are well integrated to make them small and lightweight [5]. Their fuel-saving ability also results in a smaller fuel tank. These are the reasons why an inverter generator is so easy to store and transport; it can fit a car.

A traditional generator is only portable because a set of wheels can be added to it so it can be dragged out of its storage [8].

  • Parallel operation

Many inverter generators can be linked or paired with identical units to double the power capacity. The parallel capability of an inverter generator allows the use of two smaller, lighter generators to do the work of one large generator. The generators can be stacked or placed side by side to harness the power of two units with inverter parallel cables. 

This pairing is not possible with conventional generators. They do not have this feature. They cannot be paired with identical units, and they need special cables to connect them to their output [4, 5, 6].

  • Easier maintenance

Inverter generators are easier to maintain than those of other types. With the use of less fuel and oil, there’s less residue in it but longer running time. With it being inverter-equipped, its fuel lines, gaskets and carburettor need not be changed regularly. The battery can also be inspected only once a year [4].

Disadvantages of an inverter generator

There is only one major disadvantage that an inverter generator has: price.

The regular generator has its spare parts readily available at low prices because of its simple design and functionality. When compared with this regular type that is cheap and less costly to repair, the inverter generator is more expensive. With the significant improvement and newer technology in an inverter, it’s inevitable to have a higher cost associated with it. A better product surely comes with a higher price [4, 7].

The other drawback of an inverter generator is the low energy output. Although it’s compact and its output is cleaner or of high quality, it is not as powerful as those of its larger counterparts. An inverter generator is more suitable for occasional use like camping, which doesn’t require a lot of power.

Care and Maintenance of a Generator

The process of maintaining a generator is similar among the three types. What’s important is to follow the maintenance schedule indicated by the manufacturers on each type. Generator maintenance includes the following practices [3]:

  • General inspection to check for leaks and assess oil levels. Oil should be changed according to the manufacturer and how often the generator is used.
  • Annual fuel cleaning and filtering because diesel fuel degrades quickly. The process uses biocides in all generators except for the standby type, in which it will attract moisture.
  • Cooling system maintenance by checking the coolant level at existing intervals.
  • Checking of the battery power, terminals and cables to make sure it’s robust and sufficiently charged to last longer.
References: [1] Berendsohn, Roy. “How to Safely Use a Home Generator.” Popular Mechanics, 27 Apr. 2020, www.popularmechanics.com/adventure/reviews/a11855/home-generator-101-how-to-power-on-when-the-power-goes-out. [2] “Inverter Generator vs Regular Generator: What’s the Difference?” Norwall Power Systems, www.norwall.com/power-expert/generators-and-inverters-whats-the-difference. [3] “The Ins and Outs of Generators: The Types of Generators and Proper Maintenance.” Grainger, 1 Mar. 2017, www.grainger.com/know-how/equipment-information/kh-types-of-generators-and-maintenance. [4] “Inverter Generators Vs Generator ~ Which Is The Best?” Rural Living Today, rurallivingtoday.com/generators/power-inverters-vs-generators-which-best/#What_is_a_generator. [5] “Inverter Generator Advantages.” Honda, powerequipment.honda.com/generators/inverter-generator-advantages. [6] Lepperd, Kelsey. “Inverter Generators 101.” Absolute Generators, 4 May 2016, www.absolutegenerators.com/blog/inverter-generators-101. [7] Smith, Steven. “Portable Inverter Generator 101 – What, Why and How.” Powerstuffs, 2 Mar. 2021, powerstuffs.com/inverter-generator-101. [8] “Pros and Cons of Inverter Generators.” The Generator Expert, 16 Aug. 2019, gelawncare.com/pros-and-cons-of-inverter-generators.