Can You Run an RV Generator While Driving? (2022)

white RV driving down a road in the mountains.
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    For many people, owning an RV or motorhome is a ticket to freedom and exploration. The home on wheels provides all the essential creature comforts while allowing you to hit the road, cross state lines, and spend nights in amazing places. There is nothing quite like it. 

    With that luxury and freedom also comes a certain amount of complexity. An RV can be just as intricate as your home yet it takes more of a beating as you roll from town to town. RV ownership is a learning experience and a labor of love. 

    One of the biggest parts of that labor is understanding how your RV works. Becoming familiar with its quirks, its limits, and its potential. At the heart of this endeavor, you will often find your RV’s generator. For all those times you can’t hook up to shore power yet still need lights, an air conditioner, a fridge, a laptop charged, or any other necessity of daily living, you have your generator. 

    How much do you really know about this core component of RV living though? Here we will explore the ins and outs of running an RV generator so when you are on the road your focus can stay there and not on your power.    


    An RV in the desert.

    Not all motor homes are made equal. Some older models especially require external generators to power them.


    Types of RV Generators 

    There are different types of generators used for RVs and each of them requires special consideration. You might have a propane generator, a diesel generator, or one that runs on regular fuel but the two main types are:


    1. In-built generators: These generators are built ready to use. They are directly connected to the onboard fuel source as well as the RV’s electrical system.  These generators are often protected from the elements and can be modified to help direct dangerous exhaust fumes away from where people are. 


    2. Portable generators: These external generators are often smaller because they are mobile. You would set this up somewhere away from your RV and connect it through the shore plug. You have to be aware of exhaust and grounding with this type of generator running. Some people install these on their travel trailer if they are towing one.  


    It is important to know which kind of generator you’re using because each one has its own limitations and safety concerns.   


    When is it OK to run an RV generator?

    One of the biggest questions that people have about RV generators is whether or not you can run them while you are driving. The short answer is yes, you can. If you have an in-built generator. Usually, you can run an in-built generator under the following questionable conditions:


    • While you are driving: Because an in-built generator is fixed in position and directly connected to the RV it is perfectly fine to run it while you are driving. Take note that a generator like this will most likely be powered from the same fuel tank the engine uses. Typically the generator will shut off once you fall to a quarter tank of gas though. 


    As a general rule, it is usually not a good idea to run a portable generator while you are driving. For one, a portable generator sitting inside an RV can release toxic carbon monoxide fumes. These can be deadly. Without proper ventilation, running a portable generator indoors is not worth it. Also, if the generator isn’t secured it can slide or tip over while you are driving. This can cause fuel spills and other damage. 


    • While you are plugged into shore power: You can run a generator while you are plugged into shore power if you feel you need to. New and properly maintained systems can handle it. If your RVs electrical system is questionable however then you shouldn’t attempt it. By design, if there is already an AC current present (from the shore power for example) then hooking up the generator will cause the power source to switch. They don’t add up.  


    • When it is raining: You can run an in-built generator come rain or shine. No need to worry. A portable generator is a different story. A portable generator needs to be properly grounded and protected from moisture to avoid the risk of electrocution. You can’t just bring the generator inside though because of the risk of toxic fumes. 


    With a portable generator, you should place it outside and elevate it on a piece of flat level wood to help keep it dry. Then stake out a canopy over the top of it and ground the generator properly with a rod. Then it is safer to run the generator in the rain.  


    • During normal “generator hours” at a campsite: RV campsites often have generator operation hours which are important to take note of. You should only run generators during this time, even if yours seems quiet or you’re the only RV there. Oftentimes the operation hours are in place for people and wildlife. 


    These are just a few of the key situations when you might wonder if it is OK to run a generator. The main concerns are always about connectivity and safety. In-built generators are typically more versatile because of how they are built and they only have a couple of minor concerns. Portable generators are a great option for RVs that don’t come with in-built generators but there is a lot more to consider with them as well. 


    An RN driving down the road in the desert.

    When you are on the road the motion of the vehicle can be bad for a running refrigerator.


    Keep the refrigerator in mind when driving 

    When you are driving with the generator on it is tempting to just run everything. You shouldn’t do this though. Most electrical appliances are fine but the refrigerator in the RV can have trouble functioning as you drive. Given the way that most refrigerators work the bumps and jostling of a moving vehicle can temporarily or even permanently disrupt the fridge.

    Instead, it is better to turn the fridge off while you are moving and use coolers, ice packs, and ice to keep everything cool. Other than that you should be fine to use everything else on the RV! 


    How much gas will an in-built RV generator consume while driving? 

    Since an in-built generator is typically powered directly from the fuel tank it is important to consider just how much gas it will use. Generally, you can estimate that the generator will use about one gallon per hour but this can vary from case to case. It all depends on the type of generator you have and how much you are running at one time. 

    The air conditioner and large electrical devices like TVs or gaming systems can increase fuel consumption. If possible it is usually a good idea to keep track of your gas mileage over a few days of using the generator while driving. You can subtract the RVs gas mileage from this number to see the generators average impact on fuel consumption. This will give you a better understanding of your mpg and generator fuel consumption.          


    When is it not OK to run an RV generator?

    Knowing when you shouldn’t run an RV generator is extremely important. This is a matter of safety and if it isn’t followed appropriately there can be serious consequences including illness and even death. There aren’t too many hard and fast rules on this but experienced RV users usually caution the following:  


    • You shouldn’t be running a generator while you sleep: This can be one of the most dangerous times to run a generator on your RV. People have died. The major concern has to do with the exhaust fumes from the generator which include carbon monoxide. Carbon monoxide is colorless, odorless, and tasteless yet it is flammable and if you breathe too much in it can kill you. The carbon monoxide slowly displaces oxygen in your blood and deprives the vital organs of the oxygen they need. 


    If you want to run an RV generator at night then you need to implement some key things. First, you need to have a professional check the exhaust on your inbuilt generator. If you are using a portable generator then you should know where the exhaust port is and make sure it is pointed away from the RV and positioned far enough away from where anyone sleeps, especially other campers in tents.

    Once the exhaust is attended to and cleared then you need to install a carbon monoxide (CO) detector. Even if you aren’t using the generator at night you should always have a loud functioning CO detector in an RV. This one piece of equipment can save your life.    


    • You shouldn’t run a generator when you are away from the RV: According to Crossing Creeks RV Resort 35% of all RV fires in stationary RVs are caused by electrical shorts and faulty wiring. Running RV generators are a huge part of this. Aside from the carbon monoxide risk we already covered, an RV generator is a fire risk.


    When faulty wire sparks and ignites a fire, that can quickly turn into a blaze that destroys not only your RV but potentially the forest and other property around it. This is much more likely to happen when the generator is running and you aren’t around. If, however, you are there, you might be able to put out the initial fire before it grows. 


    • While refueling: You should never run a generator while adding fuel to it. This also creates a dangerous fire risk but this time you can get seriously hurt. This is even more dangerous near a gas station. The fuel you are adding to the generator releases fumes which can ignite from a spark in the generator. If that happens it can result in an explosion. Always keep a note of your fuel level as well, that way you don’t overfill. 


    These are the key times that running a generator can be the most dangerous unless you have properly prepared. Carbon monoxide and fire risks are a reality of living with electric generators so they should be considered seriously. 


    A white RV on the grass.

    Park in a cool and shady spot and you won’t have to use the AC as much.


    How can I reduce how often I use my RV generator? 

    We are accustomed to almost always having access to instant electrical power, especially in the United States. For that reason, it can feel like you need to have the same in your RV so you are compelled to run the generator full time. In reality, this isn’t necessary. Because an RV is usually a smaller short term space you can comfortably live in it with much less power. That’s part of the spirit of RVing anyway. Sometimes you don’t need power at all! Consider these tips for reducing electricity usage in your RV so you can run the generator less and conserve fuel. 


    • Use ice packs and bags of ice to help keep the refrigerator cool 
    • Limit how much you open the refrigerator door so you can keep more of the cool air inside
    • Use a special refrigerator built for RVs which stays cool longer and uses less power 
    • Park the RV in cool and shady locations to minimize air conditioning use 
    • Use sunshades on all windows to help keep the sun out and the cool in 
    • Use an insulating curtain or something similar to separate the driving cab from the rest of the RV. The windshield is a huge source of heat and the driver’s cab usually has the least insulation so cool air escapes there too. 
    • Consider other electrical power sources like solar power or wind power. If the top of your RV is unused then you should definitely install a solar panel or two. These alone can power most of your RVs needs and the generator could become a backup power source for those dark and gloomy days. 


    There are many creative ways to take advantage of the condensed space and utility of an RV so that you don’t have to rely on a running generator as much. The more you use an RV while looking for ways to cut down on generator use, the more ways you will see how to do so.         


    How long can you run a generator in an RV?

    The potential run time for a generator depends on what kind you have. Portable models can run anywhere from 8-20 hours straight while some in-built generators can go for days. As we have noted before though, these extended run times aren’t the safest because it increases the risk of fire and carbon monoxide poisoning. It all depends on what kind of equipment you have, what safety measures you have put in place, and what kind of risk you are willing to accept.  


    How often should I run my RV generator?

    Safety and maintenance are a large part of being able to run a generator under many conditions. A well-serviced generator can perform better while you are driving or during a severe heatwave when you want to blast the roof AC and the dash air isn’t enough. For the purposes of this article, one of the important maintenance questions is how often should a generator be run?

    Most manufacturers suggest that a generator should be run under load at least once a month. This doesn’t have to be anything crazy though. Just start up the generator and run all the basic appliances you might have going while camping or on the road. In addition to this load testing, you should also perform all the other regularly required maintenance for your generator to keep it in tip-top shape.     


    What is the best generator to use for an RV? 

    There is a dizzying amount of generator options out there for RVs so it is difficult to say which one is the best of them all. Instead, it is more useful to discuss what to look for in an RV generator.


    • Long run times: If you intend to use your generator all day then you want one that is suited for it. In-built generators usually are but portable generators come in a wide variety. 


    • Large fuel capacity / lower fuel consumption: You want a generator that gives you more bang for your buck. This means portable generators that can hold more fuel and generators that consume less fuel for comparable outputs in power. 


    • Size: How much do you need to power? The bigger your vehicle the more you probably need to power. You want to make sure you have a generator commensurate with your needs.  


    • Fuel type: Check out the pros and cons of each fuel type when you’re looking at portable generators. Propane is considered the greenest fuel if you are aiming for cleaner emissions. 


    • Noise: A seemingly perfect generator that checks off all your boxes might surprise you when you actually start it up, it might be louder than a jet plane. You should check the decibel (db) noise level of a generator. Go for the quiet one no matter what, remember, you have to live with the sound of this. 


    Three white RVs by the ocean.

    An RV or motorhome is a ticket to adventure.


    Final Verdict:

    With a built-in RV generator, you have flexibility in what you can do. You can run it while driving, while it is raining, and even while connected to shore power. Portable generators don’t offer you the same options. Both types provide essential electrical power though but safety must always be front and center in your mind. Fires and carbon monoxide poisoning happen all too often due to poor maintenance and poor preparation. 

    With the right generator and the right precautions, you can be happily situated with a powered RV whether parked in camp or on the road.


    Bonus tip: Check out these amazing up and coming RV innovations at the RVX 2019 tradeshow!   



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    Riley Draper

    Riley Draper is a writer and entrepreneur from Chattanooga, Tennessee. As a world traveler, he has been to more than fifty countries and hiked some of the most elusive trails in the world. He is the co-founder of WeCounsel Solutions and has published work in both national and global outlets, including the Times Free Press, Patch, and Healthcare Global. When he's not writing, he's probably on a hiking trip or climbing in the mountains.