Are Propane Generators Quiet?

Generators are notoriously noisy machines that can upset the neighbors and even violate local noise laws. However, a generator may be necessary with aging, unstable, or under-capacitated power grids rather than a nice-to-have. Propane generators are growing in popularity and might be the generator of choice for many people.

The noise level on a propane generator is between 45 and 80 decibels, depending on the generator’s size. All generators make noise, but propane is generally considered quieter than standard gasoline or diesel-powered generators.

A quiet generator runs at noise levels lower than 65 decibels. When manufacturers measure a generator’s loudness, they do so at a distance of 23 feet, or 7 meters, from the generator when standing in an open field. The closer you get to a generator, the louder it is.

How Loud Is the Noise from a Propane Generator?

Most propane generators produce as little as 60 decibels of noise, the same volume as a normal conversation. The bigger ones can go up to 72 decibels.

The noise level of a generator is an essential consideration before you buy one. If you live in a built-up residential area and purchase a too loud generator, you could end up being unable to use it due to noise complaints. Also, municipalities and states are increasingly regulating noise in residential areas to prevent rising levels.

Imagine what would happen if each home in a housing estate bought big noisy backup generators to use during power cuts. The sound could be deafening. High noise levels affect people’s quality of life and can also stress pets. Worse, they can cause hearing loss and affect one’s ability to communicate effectively.

If you are a contractor servicing homes and businesses and need a generator to power your tools, you may lose clients by bringing a loud, smoking generator into their living or working space. You may even face occupational injury claims from employees forced to work too close to the generator. 

Quiet generators are valuable on job sites where crew members need to hear and understand instructions and work seamlessly together. Constant, loud noise can interfere with concentration and communications and cause unwanted distractions.

Campers also need quiet generators to use at camping sites not to disturb the rural quiet that everyone is seeking and keep arguments with fellow campers down to a minimum.

The Heavier the Load, the Louder the Generator

A few decibels ‘ noise ramps up for each electrical appliance you plug into a generator due to the increased load or power demand. A fully loaded generator runs at a higher noise level than one that only powers a couple of appliances, such as a refrigerator and a lamp.

There is little resistance within the alternator’s magnetic fields when there is no load on the generator, so the engine can freely spin it. When you initially plug in your household appliance, you will notice the engine noise seems to slow down before it recovers and speeds up again.

The Location of a Generator Affects Noise Levels

In residential areas with small gardens where the houses are close to each other, you may not have the space to move a generator far enough away to achieve the necessary noise reduction or meet safety concerns.

Remember that manufacturers measure a generator’s noise level at a distance of 23 feet. Up close, it can be much louder. If there are sound-reflecting surfaces nearby, they can amplify the noise to much higher levels than those in the manufacturer’s specifications.

I don’t think you can avoid noise complaints from neighbors by operating the generator inside your house. You should take the threat of carbon monoxide poisoning very seriously, as it can be deadly for your family. You should always place your generator at least 20 feet from your home, with the exhaust facing away from doors and windows.

According to a Centres For Disease Control (CDC) study, almost half of non-fatal carbon monoxide poisoning reported in the 2004 and 2005 hurricane seasons involved generators running less than 7 feet from the house. Lack of wind, or slow wind speed, adds to the danger. The CDC says you should locate a generator as far away from your house as possible.

Locating your generator a safe distance from your house brings the noise factor into play again. If you place a generator too close to the perimeter of your property, your neighbors may object. It is therefore advisable to buy the quietest generator you can afford.

If you live on a farm or large property, the noise will not be as much of a problem. You can store the generator in a shed or outbuilding away from your house and the neighbors.  However, it is safer to keep propane for long periods than gasoline, which rapidly deteriorates.

Generally speaking, permitted noise levels in North America during the day are around 60dB and approximately 50dB at night. However, local authorities have set even lower noise limits in certain zones. 

If there are garden walls or buildings close to the generator, they can amplify the sound. When there are no reflecting surfaces, the noise reduces by 6 decibels every time the sound source’s distance doubles.

While the manufacturer’s decibel measurement is useful, the generator could be louder than indicated in the specifications, depending on where you place it.

How Do Propane Generators Compare to Other Generator Types

Propane generators have several advantages compared to gasoline and diesel-driven ones. Apart from being significantly quieter, they also don’t generate the same degree of air pollution because they burn cleaner.

It is much safer to store large quantities of propane for use in an emergency than the same amount of gasoline. The latter is highly combustible and also decays much faster than propane. The shelf-life of propane is virtually limitless.

Gasoline containers emit flammable fumes as the gas evaporates, whereas propane cylinders have valves that prevent leakages. It is impossible to safely store significant quantities of gasoline in or around your home. However, you can safely store as many propane tanks as you have space for.

If the electrical grid is down, you may not be able to buy gasoline because fuel pumps run on electricity. Propane can still be purchased from your local hardware store or even delivered to your home.

Propane, unlike gas, does not expire and is much more eco-friendly. It is also cheaper than gasoline.

Propane is colorless and odorless, so it is better for people with lung problems like asthma. Filling a gasoline-driven generator carries a high risk of spillage, and you are breathing in the fumes as you pour it into the tank. There is none of that with propane generators.

How Is Generator Noise Measured?

The decibel scale is logarithmic, meaning that a generator at 70 decibels is ten times louder than one at 60 decibels. The quietest audible sound, perceived by the human ear as nearly total silence, is 0 decibels. A sound at 10 decibels is ten times louder. A sound at 20 decibels is 100 times more audible than 0 decibels. At 30 decibels, a sound is 1,000 times louder than 0 decibels.

The National Institutes of Health (NIH) measured the sound of people laughing at 60 to 65 decibels and a quiet office environment at between 50 and 65 decibels. A vacuum cleaner is around 70 decibels, and garbage disposals, or city noise, is 80 decibels.

One 7-kilowatt propane generator was recorded at 68 decibels at a distance of 23 feet compared to another 6.5-kilowatt gasoline generator, which recorded 77 decibels. That is a difference of 9 decibels, which means the gas generator was almost ten times as loud as the propane generator.

Manufacturers often print the noise levels of the generator on the information manual or packaging. It is essential when comparing for noise that you consider generators with similar power outputs. The larger the wattage, the more noise the generator will make.

The loudness of a generator can depend on the make, age, model, and manufacturer. When shopping for a generator, make sure that you ask the retailer the relevant questions. If he does not know the relative noise levels of the generators he sells, go to another shop that has the answers.

Conclusion

Propane generators are generally quieter than diesel and standard gasoline generators, but they do make some noise.  Inverters are the quietest generators available and run on gasoline, but they are usually more expensive. Propane is often recommended for lower noise levels and also because it’s cheaper and burns cleaner.

Sources

Hubert Miles

I've been conducting home inspections since 2002. I'm a licensed Home Inspector, Certified Master Inspector (CMI), and an FHA 203k Consultant. I started PickGenerators.com to help people better understand whole-house and portable generators.

Recent Posts