What Do RV Generators Run On? Most Common Fuels

There is a lot of confusion when it comes to learning what kind of fuel RV generators run on. A lot of information is out there about the different types of generators and how they work. It can be difficult to narrow it down. This guide can help you choose the right one for your rig and your situation. 

There are three fuels that the majority of portable and built-in RV generators run off of, gas, diesel, and propane. Each type of fuel and generator has its own pros and cons. Things such as cost, ease of use, and how easy the fuel is to get and store will all factor into your decision.

You’ve landed here for one of two reasons. You are trying to make an informed decision before you buy an RV generator. Or you’re interested in learning more about the one you have. There’s a lot to that old saying “knowledge is power”. Continue reading and I will share what you need to know about the fuels that most RV generators run off of.

The 3 Fuels for Built-in RV Generators

There are 3 types of fuel that are most often used to power built-in RV generators: diesel, gas, and propane. Built-in gas and diesel RV generators may have the option of using the rig’s fuel tanks as well as their own.


Diesel-fueled generators are a top choice of RV manufacturers. They cost less than most others and are the most fuel-efficient. They also tend to require less serious maintenance. Diesel is the cleanest burning of the three fossil fuels. 

Diesel fuel may be the most cost-effective choice, but it is also the noisiest running of the three. Diesel can be stored for about 6 months before it will become unusable. It’s a good idea to empty the tank before storing the generator.


Gas-powered RV generators are popular because of the ready availability of fuel. These generators often use your RV’s fuel tank. This can be a good thing or it can become a problem.

A possible issue with the generator drawing gas from your rig’s tanks is that you could drain it. This is a real problem if you’re dry camping 50 miles from the nearest gas station or civilization. Newer generators and RVs have a safety shutoff system if you get down to a quarter of a tank.

Gasoline has a fairly short shelf-life of about 3 months. It doesn’t take long for it to go bad and this could damage your generator. Regular maintenance can help keep this from happening.


Propane generators are the least efficient choice. They tend to burn through the fuel much faster than either gas or diesel. It can also be the most expensive fuel. One of the main benefits of having a propane generator is that it is the easiest fuel to find, store, and transport. 

Many of your rig’s appliances may run on propane so you are likely to have large tanks already on board. Because propane is stored in a sealed tank, it has a much longer shelf-life than the two other fuels. When weight is a consideration, propane is the lightest of the three.

Common Fuels for Portable RV Generators

Most newer model motorhomes, trailers, and other RVs are sold with built-in generators. You have several options if your rig doesn’t have one or you’re looking for a portable RV generator. Portable units can also be used as an emergency power source at home. Most RVers will decide on a unit based on the fuel that the portable RV generator runs on.

We’ve already discussed the 3 popular fossil fuel options above. These are the most common fuels you will find when looking at portable generators. Portable generators will have their own built-in fuel tank or, in the case of propane, have the ability to connect to an external tank.

When looking at a portable RV generator, one of the top concerns will be weight. There will be times when you need to be able to move it around. It may be “portable” but it could also weigh well over a hundred pounds, especially when full of gas or diesel. Weight can also become a consideration when you’re on the road. Keep an eye on your rig’s weight limits when shopping for your generator.

Photo ID 132862819 © Oskanov | Dreamstime.com

Portable generators also have dual-fuel and rechargeable battery power options. Both types are easy to find and easy to operate.

Something to keep in mind with portable generators is storage and security. In my article, I’ve covered some of the best ways to Secure Your RV Generator for Travel and Security.


A dual-fuel generator allows you to use either gas or propane. The unit has a gas tank, but it also has a fitting for a propane tank. This is a great option when you have multiple fuel sources and needs. It can be set up as a standby generator while on propane and then be used as a regular portable power source.

Dual-fuel generators are in the middle of the price range. They are becoming a popular choice due to the new technology and the flexibility of fuel sources.


The quietest and usually the lightest, a rechargeable battery powers this generator. Most of these units will need to be plugged into an electrical source to recharge, although some are coming with a solar panel option. You can also set up your own solar panel system on your RV as we did and connect it to your generator.

As with the others, there are some downfalls to battery-operated generators. The better units are on the pricey side. The smaller, more portable ones don’t put out as much power as similar-sized generators. The batteries may also take some time to charge, unlike the others which are operational as soon as you add fuel. 

Basic Maintenance For RV Generators

Your generator can supply you with extra power for years if you take care of it. Most models don’t need extensive maintenance. You can take some simple steps to keep it operating at its best. The owner’s manual has suggested maintenance specific for your model.

  • Run it often, even if you’re not using it. By running it for a few minutes once a month, you will help it keep lubricated. This also helps with reducing any moisture buildup.
  • Inspect your wiring for any breaks or loose connections.
  • Make sure there are no oil or fuel leaks.
  • Check the exhaust for any obstructions, cracks, or damage. 
  • Don’t let it sit with old fuel when in storage. Drain it or use the fuel up by letting the generator run. 
  • For the most part, battery-operated generators just need their batteries charged regularly. It is a good practice to never let the battery go below 50 percent.

If you are having issues with your generator starting then shutting off, we have an article dedicated to how to fix a generator that keeps shutting off.

Closing Thoughts

There are times when it isn’t convenient or possible for you to plug your RV into an electrical source. Knowing your generator is there as a backup is a comforting thought. It is also nice to realize that you have several options to choose from when you’re looking for an RV generator. 

Consider the cost of the generator, fuel type, and its efficiency. Know what you’re planning on running off the unit and buy accordingly. If you’re just going to use it for a fan and your laptop, pick that whisper-quiet battery generator. If you’re planning on keeping those 2 AC units blasting arctic air all day and night, get that big diesel generator. 

You are probably curious about the length of time you can run a generator. I have a full article dedicated to this topic, How Long Can You Run an RV Generator? Plus Tips to Save Fuel.

There is no need to leave the creature comforts behind when there’s a generator out there that will fit your needs. Be confident and take that road less traveled, you won’t be sorry.

Related Questions

Can you run an RV generator while driving?

Yes, you may need or want to run the generator while driving. Besides keeping your refrigerator cold, it might be necessary to run the rooftop AC. It may be for passenger comfort or because you need to turn off the dash unit to gain extra mountain-climbing power.

Something to consider before you take off with the generator running is to make sure your gas tank is full. This is important if your generator shares a tank with your RV. Many states and localities prohibit the use of propane while driving or in certain areas. It is important to check the laws where you’ll be traveling. Be sure that your generator’s exhaust is vented outside.

Can I leave my generator running all night?

The answer to this question is also yes, but with some things to take into consideration. First of all, make sure you have a functioning CO (carbon monoxide) detector installed in your rig. If your generator is sharing the rig’s fuel, you’ll want to make sure that the tank is full. A portable generator can run anywhere from 4-10 hours or more depending on the fuel type and tank size. Most generators have an automatic shut-off so the unit won’t run empty.

Noise is another thing to be aware of, especially at night while your neighbors are also trying to sleep. Diesel generators are the noisiest of all while battery-operated units are the quietest. A lot of it will depend on what you’re powering overnight. If you’re keeping it cool with the AC unit, most battery-operated generators don’t put out enough juice. If you’re just wanting to power a fan, the battery unit would be fine. When shopping for a generator, it is helpful to know what you plan on running off of it ahead of time. 

Diane Dee

Diane is a lover of all things travel. She and her young family wanted to explore North America from the comfort of their own home so they bought an RV. After fully rehabbing a 1994 Safari Trek, they set out to explore both Canada and the USA.

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