When looking at buying a generator, noise levels are usually a major factor. Many manufacturers state their portable generator noise levels on the spec sheets, but how do these noise levels relate to the real world? We’ll try and explain generator noise levels below so that selecting the right portable quiet generator for your own specific purposes is a little easier.
Real World Noise Levels
The ‘loudness’ of a portable generator is generally expressed in decibels (dB or dBA) – the higher the decibels, the louder the unit is. For the sake of comparisons, a ‘normal’ conversation is usually around 60 decibels and a vacuum cleaner is up around 80 decibels. In addition, for every 10 decibels the generator noise level is 10 times greater in loudness – so a 70 decibel rated generator is 10 times as loud as a 60 decibel rated generator.
Another way to consider the noise level of the portable generator you’re looking at buying is to see where it sits in the decibel noise comfort range:
- 10-30 dB is considered ‘faint noise’
- 40-70 dB is considered ‘moderate noise’
- 80-90 dB is considered ‘very loud’
- 100-120 dB is considered ‘extremely loud’
- 130+ dB is considered ‘painful’
Generally speaking, the quietest generators have ratings under 60 decibels. Bear in mind, that the stated decibel levels are generally measured at 7 meters away from the unit. The actual noise level of any generator is going to be much higher than the stated level when standing beside the unit.
Factors that will affect your generator noise level:
- Power output: More power output will always result in a louder generator. E.g. a 4000W generator will be louder than a 2000W generator. In addition, the decibel level will also change with the load required from the generator – running more or less appliances
- Ambient surroundings
- The exhaust of the generator
- The cooling fan(s) of the generator
- Mechanical noise from components such as the alternator etc.
Inverter Generators vs Conventional Generators
Inverter Generators tend to be much quieter than conventional generators. This is mainly due to their efficiency in producing electrical current thus needing a smaller motor, meaning less noise. Additionally, the also usually have a body casing which reduces the overall sound. Inverter Generators are the quietest generators available and should be considered when noise levels are critically important such as for Food trailers and food trucks operating in noise sensitive locations, or for motor homes, caravans and camping sites where noise pollution may affect other people nearby.
Ways to make your generator quieter
- Move the generator away further. This is by far the simplest solution to noise. Invest in good quality extension cords such as the 28A Rated Cord. As a rule of thumb in an outdoor space, when you double the distance you get a 6 decibel noise reduction.
- Correctly position the generator. Ensure the unit is mounted on a flat, level surface and point the exhaust away from your site (the exhaust is the loudest part of a generator). If not mounted correctly, additional noise and vibrations can occur.
- Make an enclosure for the generator. This is a very effective way to reduce the noise level of the generator, but be very careful to design the enclosure to ensure adequate ventilation and exhaust for the generator unit in order to prevent overheating. A correctly designed enclosure will result in a very quiet generator – up to 10 decibels quieter!
ConclusionThe fact of the matter is that portable generators make noise, and quite a bit of it. There is no such thing as a silent generator. Make sure you size the unit correctly (see our choosing generator blog) for your needs, and then consider the information above in order to best minimise the generator noise level.