How Loud is a Generator?

Image by Mudassar Iqbal from Pixabay 

When you decide to buy a generator, you may quickly realize that most of them produce a lot of noise. If you live in an urban or suburban area, chances are you need to follow regulations on noise pollution, especially at night. In these, and a lot of other cases, having a noisy generator can spell trouble. Even though you need them. 

Fortunately, most generators come with specifications about loudness. However, the question remains—How loud are they?

We recommend you read this guide on the best predator generators or the best propane generators.

How Loud is a Generator?

To explain how loud a generator is, you first need to know about decibels. The decibel, commonly shortened to dBA (or dB), is a unit scientists use to measure the intensity of a sound. 

As our ears are extremely sensitive, we can hear a wide range of sounds from quiet (see the best quiet generators) whispering up to a meter away to warning sirens and Jet engines. Our ears cover about 14 orders of magnitude (1014) of noise. Take a look at the following list to see how much decibels some common sounds have:

  • Washing machine – 70DbA
  • Traffic noise heard from inside a vehicle – 80DbA
  • Leaf blower – 90DbA
  • Sporting event – 100DbA
  • Rock concert – 110DbA
  • Siren 120DbA

Different generators with various power production also produce different amounts of noise. A large portable diesel or gas generator can produce roughly as much as a leaf blower(80DbA). An industrial or commercial grade generator may even be as loud as the being in the first row at a rock concert (approx. 110DbA).

Which generators are the quietest?

Size isn’t the only thing that decides the amount of noise a generator will make. For instance, you may need to take into account things like the year of production, manufacturer, and most importantly, injection and fuel types. These things may sound very complicated at first, but they aren’t.

Before continuing, we recommend reading about the best small generators.

Here’s a quick explanation of them:

Production Year 

Ever since the day of the Ford Model T, engineers all across the board have been trying to make more efficient, quieter, and safer generators and engines. In our time, almost 190 years after the invention of the first electric generator, most modern generators are safe, easy to use, and almost completely silent. 

Due to the rise of Internet and computer technology, generators today use complex, CPU-guided mixes of air and fuel to create the perfect ratio. Some modern generators even come with a specialized laptop, computer, and phone charger accessories. Modern large generators also use V8 configurations to reduce vibrations and RPM CPUs to calculate optimal fuel usage. 

Injection Method and Design 

Open frame generators are named after the fact they incorporate large, open designs with nothing covering the loud, bulky pistons. Since nothing covers the noise-making part of the machine, you don’t have any sound reduction.

Meanwhile, inverter engines are the cutting-edge of quiet, portable, and economic power generators. Largely due to their enclosed design and inverter fuel injection technology, they can be as quiet as 50 – 60DbA. This is significantly quieter than even a washing machine or suburban traffic. Open frame generators, which are commonly used on worksites and around the farm, are around 70 – 80 DbA.

Fuel Type

This mostly applies to diesel-fueled non-inverter generators. Portable diesel generators are normally found to be around 75 – 85DbA, largely due to the fact diesel fuel uses pressure to generate power, creating louder and more volatile explosions than other fuels. 

However, at a lower running speed and a good, sound-insulating canopy around the engine can make all the difference. Other fuels such as gas and petrol are much easier to use due to them requiring sparks to create a quieter, more controlled explosion.