How To Quiet A Generator For Camping: 6 Smart RV Hacks

If you prefer to boondock away from the crowded RV parks and campground, then you’ll most likely need an RV generator for your power needs. One thing to take into consideration is the noise it makes, which might disturb nature’s tranquility, scare off wildlife and make it difficult to sleep. Thus, knowing how to quiet a generator for camping will significantly enhance your camping experience as well as making sure you’re following local noise regulations.

Most RV generators are as loud as a vacuum at 60-90 dB and sometimes higher, while the noise limit at certain national parks is typically 60 decibels at 50 feet from the source. This means to be on the safe side, unless you have purchased a high quality generator that is quieter than this threshold, you will need to pocket a few hacks on how to quiet a generator. Worry not! This article will teach you where exactly the noises are coming from, the principles for noise reduction and 6 methods to make your generator much more bearable. 

RV Generators

While camping in an RV park or campground, you can rely on the complete utility hookups available to charge your RV’s house battery bank and power your electrical appliances. However, if you prefer to travel off the beaten path and therefore won’t have access to the campground’s shore power, you will need another dependable power source. A generator for RV use is an absolute must-have.

An RV generator will supply power to your electrical appliances, so that you can enjoy the comfort of your own home. If you travel with companions and thus have higher than average power consumption, especially if you need to run power-consuming appliances like the air conditioner, the best RV generator will be your best friend that ensures you will never run out of power. 

The device can also charge your RV’s house battery bank. It is also useful in case you need a direct source of power for your 120V AC outlets, where you can plug small devices and appliances, such as your laptops and hair blow dryer, providing you with all the onboard conveniences you need. 

Related: Best RV Solar Generators

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Why You’d Want to Pay Attention to Noise Level

In use, power generators tend to make some noises but certain models on the market make less noise than the rest. If you run the generator at night, the noisier models might disturb the light sleepers. It’s also worth noting that various camping grounds for recreational vehicles, particularly National Parks, have regulations regarding the sound levels of generators. The noise limit is typically 60 decibels at 50 feet from the source.

That means if you use a generator that proves way too loud, few locations would welcome you and your RV. The best RV generators on the current market are relatively quiet, but you’ll want to make sure.

Noises produced by portable generators for RV usually fall between 60-90 dB, but certain models can go over 100 decibels. Meanwhile, inverter generators for RV are generally a bit quieter. For comparison, a typical RV vacuum cleaner makes about 60-70 dB of noise. 

This level of noise is bearable in small bursts, but over time, especially in the tranquil camping setting, it can get more disturbing over time and ruin your time enjoying nature, plus it is more than sufficient to scare off wildlife. Not to mention that the typical range of minimum 60 dB is in violation with most states’ noise restriction. 

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Where Does The Noise Come From?

Before we begin listing hacks on how to quiet a generator for camping, you should have an understanding of how a generator works and what components produce noise in operation, so that you can find effective ways to dampen that particular source. 

An RV generator works with the help of a motor fueled by either diesel or gasoline. Somewhat similar to the internal combustion engine in your car, the generator is a mechanical machine that creates combustions as a means of generating energy to keep its motor turning. The input for such a combustion include air and fuel at an optimal ratio, just like with your car’s engine.

There are various motor designs, from the simple ones or the more complex. A simple motor powered by gasoline often has two cylinders, each containing a piston attached to a crankshaft.

The cylinders also feature an air input port and a fuel input port where air and fuel enters the cylinders, a spark plug to ignite the air and fuel mixture,  and an exhaust port, where exhaust generated from the combustion escapes. In case of a diesel-motor generator, there is no spark plug, as the machine achieves combustion using highly compressed and thus easily ignited diesel.

The two cylinders are designed in such a way that in case one of them ignites, the remaining one will start to receive air and fuel. This mechanism ensures constant firing so that the generator continuously generates power. 

Noise Sources

Similar to the engine in your car, a generator’s noise comes from six major sources. These sources include engine noise, engine exhaust, alternator noise, cooling fan noise, induction noise, and mechanical noise. Different types of generators, for instance, standby generators and portable generators, have different noise levels due to their different construction and mechanism. 

Factors That Affect Noise Level

Location of Your Generator 

The very first thing to pay attention to when learning how to quiet a generator for camping is where you place your generator. Placement of the generator is one important factor that you can most easily influence without breaking the bank or without complicated installment. 

The type of material on which your generator sits does matter. Certain hard surfaces like asphalt, metal, wooden and concrete are a big no no, because they work as amplifiers. This is especially if your generator cannot be stable on it, so it will vibrate against the surface, amplifying the noise a lot more. 

Instead, place the generator on stable and soft ground like flat soil or on the grass. The ground will absorb the vibrations, thus dampening the noise that will reach you. Very effective and easy to do. In case this is not feasible or you would like more flexibility, you will find simple and affordable accessories for this purpose further below. 

The Generator’s Size

Another factor deciding how loud your generator is is the unit’s power output. Due to the working mechanism of generators, that is by creating many combustions, more internal combustion equals more power but it also means more noise. So larger generators with larger engines that produce more power are naturally more likely to be noisier.

This is especially true in dated, cheaper models. Although the extent of quietness depends on each model, you can generally expect more expensive, higher quality generators to come with one or a few noise reduction features, even at higher energy outputs.  

Related: What Size Generator for 30 Amp RV?

Cooling System

Like any type of motor, a generator’s motor produces a lot of heat and thus to ensure smooth operation, it requires a cooling system to prevent overheating. The cooling system contributes to the noise level that a generator makes. Standby generators can either be air-cooled or liquid-cooled. Air-cooled systems are louder, while liquid-cooled systems are quieter. 

Engine Casing

As for portable generators, the two primary noise sources are the engine block and the exhaust system. The engine of a portable generator is typically louder than those in your car due to different casing materials, plus the type of cooling system. 

Vehicle engines are encased in steel, which insulate sound quite well, and are liquid-cooled. On the other hand, portable generators’ engines are air-cooled and encased in thin materials that don’t insulate sound very well.    

The Muffler’s Condition

Another mechanical part in your generator responsible for causing annoying noise is a malfunctioning or simply old muffler. Your generator should come with a muffler attached to the exhaust. As its name suggests, the muffler’s job is to muffle, or reduce, the sound coming out of the exhaust pipes attached to the motor of the generator. Needless to say, a malfunctioning muffler would result in your generator being more annoying than usual and would require an inspection, possibly a replacement.

Technology 

Later generators equipped with more advanced technology are most likely quieter than their counterparts of earlier generations. 

Inverter generators are later improvements from the conventional RV generators. Instead of running at a constant rate like conventional generators, since they only work just hard enough to supply the power demanded from them at any given time. They electronically throttle the engine just to meet demand instead of running full tilt all the time. 

This makes inverter generators much more quiet as well as more fuel efficient. Additionally, these later inverter generators are typically equipped with sound deflectors and mufflers to effectively lower noise level.  

Servicing

As with all machinery, regular servicing is crucial in making sure your generator is in tip top shape. Malfunctioning of some mechanical components or ageing mufflers can cause a generator to be noisier than usual.

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How To Quiet A Generator: The Principles

The rule of science on how to quiet a generator is that you can reduce sound in one of three ways:

• Sound deflection 
• Sound absorption 
• A combination of sound reflection and absorption

Deflection will direct sound waves in a way that they cancel each other out, like what a muffler does. Noise absorption is a process by which an object takes in sound energy, thereby reducing the perceived noise and producing heat as the byproduct. 

A representative example would be the sound in a room with thick carpet. The thickly carpeted room will absorb the sound without letting too much escape – think music halls. 

And finally, you can redirect sound so that an object absorbs it.

How To Quiet A Generator #1: Distance 

You can find the sound rating or the decibel rating of most generator models nowadays to compare the level of sound between different models. These decibel ratings are measured at about 7 meters out from the operating generator in most cases.  When you go camping, always place your generator a minimum of 7 meters away if you want to enjoy the benefits that you paid for. 

Obviously, the further away you place your generator from your campsite, the quieter it’s going to get. If you’re camping in the middle of nowhere with no other campers around, then feel free to place the generator as far away as possible, considering the length of your extension cords and whether you don’t mind walking over to your generator. 

However, if you’re camping at an RV park or campground, you’ll need to keep your neighbors in mind and avoid placing it too close to their campsite.

How To Quiet A Generator #2: Put The Generator on A Soft Surface

As mentioned above, you should avoid placing your generator on any hard surfaces. Usually, the best option is to set your generator on dirt or grassy soft ground, which will absorb and dampen the noise instead of amplifying it.

If you would like some flexibility so that you wouldn’t have to worry wherever you camp, another way is to place the generator’s feet  on anti-vibration pads or placing your generator on a soundproof mat. Both are super cheap and easy methods that will reduce noise pollution significantly.  

How To Quiet A Generator #3: Exhaust Pipes 

In addition to the above two hacks, another easy way to reduce noise level is ensuring that the exhaust pipe is facing away from you. As mentioned above, the generator’s exhaust is a major course of noise pollution, so changing the position of the exhaust pipes is of considerable significance. 

When the pipes are turned horizontally, they are blowing the air horizontally, which means the noise is also escaping horizontally. Meanwhile, if the pipes are turned vertically, the noise will escape in that direction as well, which effectively means less noise reaching your ears.

To more effectively reduce the noise coming from the generator’s exhaust, a popular solution is to replace the built-in muffler with a larger replacement muffler. Many RVers swear by this upgrade, however it is worth noting that the reviews are mixed. It seems that how well the new muffler works often comes down to the right fit, that is how snugly the muffler is attached to the generator. 

In addition, another thing to consider is that most of the noise of a generator will come from the engine and mechanical moving parts, so this makes it a bit hard to really know how much noise is coming from the exhaust alone. Before spending your money on a replacement muffler, you should first do a simple test to check whether the exhaust is problematic. 

Safety first: you absolutely MUST put on gloves so you don’t burn yourself. Next, grab a thick cloth and briefly hold it over the generator’s exhaust while the generator is running. If while doing this, the sound is dampened noticeably, then your exhaust is indeed noisy and getting a larger muffler is worth it. 

On the other hand, if there is no difference in the noise level when you hold the cloth over the exhaust, the source of noise is elsewhere and your best bet is to buy a commercial quiet box, or build it yourself, which will also be discussed further below.

How To Quiet A Generator #3: Attach A Muffler To The Exhaust

If your exhaust is the major noise source, the best course of action is to install a larger replacement muffler to the generator’s exhaust. 

A muffler’s job is to, you guessed it, muffle the sound coming out of the exhaust pipes attached to the motor of the generator. Inside the muffler are perforated tubes that are designed to deflect the sound waves from the engine to lower the noise that eventually exits the exhaust pipes.

The exhaust pipes are one of the loudest parts of the generator, only after the engine itself and sometimes other moving parts.  By investing in a quality muffler that fits your generator perfectly, you can expect to quiet down the generator by around 10-12 decibels. 

This process requires some tools and skills, and can cost several hundred dollars for equipment and installation. Be advised that many RVers claim that they don’t generally reduce the sound enough to make it worth the effort and resources needed to install it.

Keep in mind that in order for this method to work, you will need to find a new muffler that fits your specific generator’s exhaust, since there are many generator types and models with different sized exhaust pipes on the market. Your best bet is to speak with a specialized mechanic, who will likely have a better idea of the choices available in replacing your generator’s muffler.

Note that if your generator is an after-market, you’ll most likely need a customized muffler for a perfect fit. 

How To Quiet A Generator #3: Sound Deflector

If you are not a handyman and would prefer no installation, sound deflectors is another great way to reduce the noise levels of your generators. The quickest way to make a generator quieter is to lean some plywood sheets against the generator. Each of the pieces should be around 4 feet wide and 3 feet tall. 

This measure doesn’t technically reduce any of the noise the generator makes. Instead, it actually keeps the noise away from reaching you. The generator’s sound will be redirected from the sheets of plywood towards the ground, which effectively absorbs the noise and quiets the generator by 10dB. This simple trick also allows for plenty of ventilation. 

Drywall is a good material for this as it is relatively fire-resistant.  Make sure to use drywall at least for the side of the generator that houses the exhaust to prevent your deflectors catching fire.

The advantage is this quick fix is easy and cheap to do with readily available materials. If you are looking for a more permanent and effective noise reduction method, you can combine sound deflectors with several other hacks in this list.

How To Quiet A Generator #4: Generator Quiet Box

Applying these rules, one measure is to build a baffle box that fits over your generator to soundproof it. They’re typically constructed from more expensive materials, e.g.  fiberglass, fiberboard, noise-reducing foam, but are just as easily broken down into a transportable medium as a few sheets of plywood would be. A baffle box will cost you around $150 dollars depending on the cost and quality of the materials you use.

One important note is to make sure that it is larger than the generator itself so it has space to breathe, as the generator needs to have enough air intake for its engine to run.

If you do not want to build one yourself and have the money to spare, you can now find various ready made soundproof enclosure for your RV generator, such as the ZombieBox. ZombieBox is a soundproof enclosure that is weatherproof, lightweight and portable. It’s also collapsable for easy storage, which makes it convenient in the camping setting. A Zombie Box will reduce the noise from your generator by up to 5X or 99%, as claimed on their website.

If you do decide to build your own baffle box, it’s a fairly easy project that will not cost you much. There are many video tutorials you can find online that will teach you how to construct one step by step. To build a DIY baffle box you’ll only need:

• Wood boards 
• Quiet board
• L-brackets
• Foam sealer

How To Quiet A Generator #5: Fit Generator Silencers

Generator silencers work the same as the mufflers do but more specifically the silencers reduce the noise produced during combustion, in addition to exhaust emissions produced during this process. Generator silencers are categorized under four main categories based on their noise reduction mechanism, and each category determines the level of noise reduction of your generator.

There are four types of silencers, plus hybrid silencers that employ a combination of two or more mechanism:

• Absorptive Silencers: This method is used to reduce high frequency sound waves. Absorptive silencers employ conventional sound reduction mechanisms, that is by using sound absorbing materials consisting of fiberglass or E glass insulation. Exhaust noise is absorbed, or dampened, as it flows through the insulation. 
• Reactive Silencer: Reactive silencers are used for low to mid-frequency noise reduction. They do not use sound absorbing materials to dampen noise like absorptive silencers but instead employ geometric design. Internal construction consists of up to three chambers connected by a tube. Exhaust noise bounces between the chambers, reducing the final output noise. 
• Dissipative Silencers: Dissipative silencers utilize flow resistance to reduce flow velocity. In other words, there is always some loss of sound energy when sound propagates, that is the dissipation of sound energy into thermal energy, which causes spatial damping of the sound waves. Diffusion also means spreading out sound energy, thus somewhat making the sound more bearable. There are different types of dissipative silencer that use different designs to effectively dissipate sound waves, including pod, lined ducts, splitters, and bars.
• Dispersive/Diffusive Silencers: Dispersive or diffusive silencers actually prevent noise generation by diffusing high-velocity turbulent gas flow to a lower velocity less turbulent flow, thus less noise is generated by the generator’s exhaust. 
• Combination Silencers: As implied, this type combines two or more technologies to reduce noise, most commonly a hybrid between reactive and absorptive silencers. That is an absorption material is fitted into the chamber design of the reactive silencer. This allows reduction of all frequency designs.

To know how much noise a silencer would reduce, look at the sound rating in dBA for a specific model. A bit different from dB, Decibel A Weighted (dBA) is a measurement used to approximate the human ear response to sound.

In the early days of rating silencers, there were four basic grades. Industrial, commercial, residential, and hospital grades. Nowadays, the industry standard for manufacturing include the following common grades, which were developed by The Electrical Generating Systems Association (EGSA): 

• Industrial Grade – Exhaust noise reduction of 15 to 20 dBA
• Residential Grade – Exhaust noise reduction 20 to 25 dBA
• Critical Grade – Exhaust noise reduction of 25 to 32 dBA
• Super Critical Grade – Exhaust noise reduction 30 to 38 dBA
• Hospital Grade – Exhaust noise reduction of 35 to 42 dBA
• Hospital Plus Grade – Exhaust noise reduction of 35 to 50 dBA
• Extreme Grade – Exhaust noise reduction of 40 to 55 dBA
• Super Extreme Grade – Exhaust noise reduction of 45 to 60 dBA

Shapes

The type of silencer is what determines its extent of noise reduction. This is not to be confused with the shape, like cylindrical, disc and rectangular silencers. Cylindrical is the conventional shape and the most economical. Disc and rectangular silencers are more compact and also offer the benefits of internal thermal insulation.

Additional Functions

Do note that other functions such as water separation, filtering, spark arresting, or heat recovery may be integrated into the silencer as well, but they do not have any impact on noise reduction. 

For instance, spark arrested silencers ensure that sparks generated in the combustion process are not emitted to the outside atmosphere. Heat recovery silencers utilize the heat from the exhaust gases, which can reach temperatures of up to 1400 degrees Fahrenheit, before it is passed to the atmosphere. This heat can be used for various purposes, including heating water. 

How To Quiet A Generator #6: Use A Water Bucket To Act As The Muffler

This sure is one creative fix, and it has been employed by countless DIYers. All you’ll need are a 5-gallon bucket of water, a hose, and clamp to secure the hose to the exhaust pipe.  Be sure to place the generator on higher ground than the water bucket to prevent the water from flowing backward into your generator’s exhaust pipe. For insurance, you can also poke a few small holes in the hose to better prevent backflow of water.

The setup is very straightforward. Connect the hose to the exhaust pipe using your clamp.  Then place the other side of the hose into the bucket of water.  The water will act as a muffler, dampening the noise coming from the generator’s exhaust. 

With tools that you most likely already have on hand, you can expect the water bucket muffler to quiet down the generator around 5-7 decibels, which is pretty decent for zero investment.

Lastly (Or Firstly): Buy As Much Quietness As You Can Afford 

Building or buying equipment to make your generator quieter is the natural course of action if you already own a generator. If you haven’t, the best thing to do is buying a generator that is quiet to begin with, given that you are willing to chip in some extra money for this perk. 

Ideally, most campers would combine the best of both worlds by purchasing a quiet generator that their budget can buy and then upgrade it with a quiet box and/or with other noise reduction mechanisms that we discussed. With all these, you will be able to run the generator in most places without breaking the regulations and it will barely be noticeable both to you and the wildlife. 

For camping purposes, you will either need a portable generator or an inverter generator, depending on your priorities and camping needs. Opt for a traditional portable generator if you need to power some power-hungry appliances like refrigerators, dishwashers or air conditioning units. Otherwise, an inverter generator might be all you need if you only need to top up your battery or laptop and some LED lights. 

An inverter generator is usually 10 dB to 30 dB quieter than a portable generator. Among inverter generators, you can generally expect that efficiency and quietness come hand in hand with cost in most cases. So you get what you pay for. In most cases, higher end models use more expensive materials and more advanced engineering to keep them lightweight, efficient and quiet.    

The quietest generators on the current market belong to Honda and Yamaha, which produces some models that maxes out around 59 to 61 decibels, which is much more bearable than a vacuum cleaner. Prices start around $900-$1000 upwards, but in addition to quietness, you can expect very well-rounded performance from these two Japanese makers as well, including fuel efficiency and durability.