How to Pick The Best Generator For Your RV
There are five important factors that will help you find the perfect generator for your RV: power output (watts), quietness (decibels), fuel type (gas vs propane vs diesel), portability (weight) and price ($$$).
This article goes over each of these categories and will help you find a generator that fits your budget, and is sized properly to work with your motorhome, 5th wheel or travel trailer. Whether your camper is big or small, this RV generator guide has the answers for your generator questions.
How Big Of Generator Do I Need For My RV?
The size of generator needed depends on how large your RV is, and which appliances, fixtures, and accessories you need to run.
To reduce the load on a generator, make sure to set your RV refrigerator and water heater to ‘LP Gas Mode’. These two appliances usually have the ability to run on either 120v electricity, or ‘LP Gas’ (aka propane).
These two appliances use a large amount of power, so setting them to use ‘LP Gas Mode’ is advantageous because it allows you to buy a smaller, cheaper, more portable generator. It’s a win-win.
Can I run my RV air conditioner from a generator?
Yes! A RV air conditioner can be powered with a generator. A common 13,500BTU RV roof top air conditioner uses about 2,800W for the first few seconds while it’s getting started up – and then once it’s up and running – it uses about 1300W.
This is a common question, and I wanted to address it near the beginning of this article because an air conditioner is the single largest consumer of electricity in a RV (when its running). The ability to run an air conditioner with generator power sometimes requires purchasing a larger, more powerful generator.
Many RV owners purchase a generator that is big enough to run their AC – however, some owners choose to buy a small, cheaper generator that does not have enough power to run an AC. Instead, they forego using the AC while running on generator power. It’s really a matter of personal preference. Your choice will depend on how you use your RV, and how much you want to spend on a generator.
The next two section go into further detail on which generators are capable of powering an RV roof top air conditioning units, as well as the rest of the electronics in a RV.
How To Calculate The Size Of Generator You Need
To calculate the size of generator that will meet your RV needs, this section will help walk you through how to add up power (in watts) of all the appliances, fixtures, and accessories in your RV.
Before we get started, you should know that you can choose to make a small generator work by not running certain items in your RV (like the AC), or by not running multiple large items the same time. With a little creative planning, you can make a smaller generator work.
For example, if you plan to shut off the AC for a few minutes to use the microwave oven or coffee pot, you can successfully use a smaller generator without tripping circuit breakers or overloading the generator.
If you do choose to be creative with how you use the devices in your RV, you can omit some items from your generator size calculation. Omit smaller items from your calculation (ones that use the least watts).
It’s better to be conservative with your generator sizing – you want the generator to have some watts to spare. This will prevent annoying circuit breaker tripping, generator overloading, and possible damage to your expensive equipment.
You get the idea, right? If you use everything at the same time, you’ll need a gigantic generator. Or, if that planning sounds inconvenient, don’t worry about it – that’s why they make bigger generators!
To calculate the size of generator you need, add up the watts of all items you plan to use ‘at the same time’. This total is the minimum generator size (in running watts) that will work for you and your RV.
It’s important to note that this calculation is based on running watts. Make sure you find the correct rating on the generator you plan to use. Keep in mind that generator manufactures usually advertise ‘maximum watts’ (or ‘startup watts’ or ‘surge watts’) prominently on the packaging. You may have to read the specifications, or fine print to find running watts.
Do not omit the refrigerator, water heater, water pump or built-in RV electronics & accessories from your generator size calculation Most of these devices turn on automatically, and you have little control over them, so they need to be included in the sizing calculation.
‘Running Watts’ Estimates
- 625W Microwave Oven: 800W
- 7,000 BTU Air Conditioner: 650W
- 10,000 BUT Air Conditioner: 750W
- 13,500 BTU Air Conditioner: 1,300W
- 15,000 BTU Air Conditioner: 1,600W
- Built-in RV lights – Halogen/Incandescent (each): 10W
- Built-in RV lights – LED (each): 2W
- Range Hood (Fan+Light): 35W
- Furnace*: 150W
- RV Refrigerator (LP Gas Mode)**: 25W
- Residential Style Refrigerator**: 600W
- Water Heater (LP Gas Mode)*: 25W
- Water Pump: 50W
- Built-in RV electronics & accessories: 100W
- 42″ LCD TV: 120W
- Coffee Maker: 1000W
- Hair Dryer 1250W
- Phone Charger 10W
- Laptop Charger: 100W
*these appliances run primarily on propane, however, some electricity may also be needed to power an electronic controller, digital display and/or fan. The RV furnace uses a significant amount of power (around 150W) because it has a large electric fan for circulating air throughout the RV.
**some high end RVs use ‘residential style refrigerators ‘which can only run on 120v power and cannot be set to ‘LP Gas Mode’. The use of residential refrigerators is common in luxury 5th wheels and luxury motorhomes. Luckily, residential refrigerators are extremely energy efficient, so they do not put a ton of extra load on a generator.
Additional Watts For Starting An Air Conditioning Unit
If you plan to run an air conditioner, make sure your generator has enough ‘starting watts’ (or ‘max watts’ or ‘surge watts’ depending on how your generator is labeled) to get the AC up and running. The large electric motor inside of an AC uses ton of extra power for the first few seconds while it is starting up.
If your generator doesn’t have plenty of extra power, it will not be able to get the AC started. To make sure an AC will work with your generator, add ‘additional starting watts’ to your ‘running watts’ total.
Many large RVs have 2 or even 3 air conditioning units. If you plan to use multiple AC units at the same time, make sure to calculate for the second and/or third AC.
Calculating ‘Additional Startup Watts’ For Air Conditioners
To see if your generator has enough power to start an AC unit, calculate ‘total startup watts’. You can find this by adding: ‘additional startup watts’ to ‘running watts’ (from the previous section) to find the total watts needed.
If ‘additional startup watts’ + ‘running watts’ DOES NOT EXCEED your generators ‘Maximum Watt’ rating, it will work!
- 7,000 BTU Air Conditioner: 1,050W (additional startup watts)
- 10,000 BTU Air Conditioner: 1,250W (additional startup watts)
- 13,500 BTU Air Conditioner: 1,500W (additional startup watts)
- 15,000 BTU Air Conditioner: 1,750W (additional startup watts)
How To Choose The Best Generator For Your RV
(Affiliate links are provided below for convenience. For more information see my disclosure, here.)
Now that you know how powerful of generator you need, it’s time to look at some of the other important factors that go into choosing a generator. The next sections will explore generator styles and sizes (form factors), fuel types, quietness (decibels), and prices!
Generator Sizes & Styles
When selecting a generator style, it’s important to make sure the generator will meet your power demands, but another crucial consideration should be portability. The generator you choose must to comfortably fit in your RV or tow vehicle, and it shouldn’t be so heavy that you cannot lift it. After all, it won’t do you any good sitting at home in your garage!
As you might expect, small generators are light weight and super portable, but not especially powerful. Medium sized and large units have lots more power, but they’re heavier and more expensive. For a detailed look into the pros and cons of each style keep reading!
1. Suitcase Style Generators
Suitcase style generators are small – and unsurprisingly – they get their name because they a suitcase. A suitcase generator is light weight – around 40 – 50 lbs. – and can be carried around by the handle with ease. Their small form factor and weight makes them highly portable, and easy to bring on a RV camping trip.
The best suitcase style generators have over 2000 watts of max capacity. This is enough power to keep up with most accessories in a small or midsize RV. Basic power demands like: lighting, refrigeration, running the furnace, television, or the water pump should not be a problem with a nice suitcase style generator.
A small generator should also have enough power to run one high wattage device at a time (such as a coffee pot, hair dryer, or microwave). However, for most RVs, running an air conditioning unit with a small suitcase style generator is out of the question – it simply will not have enough power.
These small generators are an excellent choice for RV owners who value portability, and do not need to run an air conditioner. They are extremely quiet, portable and very fuel efficient.
Small Inverter Generator – Best Value:
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If you need a bit for power for running several things at the same time, a suitcase style generator is not up to the task. For example – if lights are on, plus the TV, and the refrigerator, and the furnace, plus a laptop – and then you try to heat something up in the microwave, it’s not going to work. A microwave draws a ton of power. This extra power will be the last straw for the small generator. It will trip a breaker or into overload protection mode.
Lack of power is the main downside to a small generator. However, another limitation is their tiny fuel tanks. Suitcase style generators usually only have 1 gallon of fuel capacity. Because of this, they do not have long runtimes. Around 3 hours of runtime at max load is all you can squeeze out of a highly efficient inverter generator.
To overcome this limitation, you can purchase an external gas tank. The external tank greatly improves fuel capacity and runtime.
Best External Fuel Tank:
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A Honda EU2200i inverter generator with a full tank of gas and this 6 gallon external gas tank made by Bergs System (Amazon) can run at max power output for just over 23 hours. And if you can believe it, it can run for a staggering 59 hours @ 1/4 power.
2. Dual Suitcase Generators With Parallel Kit
An interesting generator style that many manufacturers now offer, is utilizing two suitcase generators, and combining their power with a ‘parallel kit’. The result is a combined generator with double the power. It’s a brilliant idea, and works great!
The biggest advantage of dual suitcase generators and a parallel kit is that you get double the power output with nearly the same level of portability. Suitcase generators are so small, portable, and light weight that it’s not much hard to make room for two of them.
For many people, it’s easy enough to move around two 50lb generators. Compare this to lifting one large 100+ pound generator, and you can see why many people choose to buy two small generators and a parallel kit. Trying to lift a large generator can be cumbersome at best, and may be impossible for people with back problems, or elderly RVers.
Dual Generators With Parallel Kit – Affordable Quality:
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- (2) Generac iQ2000 Super Quiet Inverter Generator – Parallel Ready (Amazon)
- (1) Generac Parallel Connection Kit (Amazon)
Another major advantage is that with dual suitcase generators and a parallel kit, they are powerful enough to run a RV air conditioning unit! These GENERAC iQ2000 inverter generators offer 1600 running watts each. With two units running in parallel, you can have 4000 max watts and 3200 running watts of power available!
GENERAC is best know for making large home backup generators. Here is some more information from the GENERAC about us page:
Founded in 1959, Generac was the first to engineer affordable home standby generators, along with the first engine developed specifically for the rigors of generator use, and is now the #1 manufacturer of home backup generators. Generac manufactures the widest range of power products in the marketplace including portable, residential, commercial and industrial generators.
That’s enough power to get most RV roof-top AC units up and running. Once the AC is started, it should have enough power left over to run several other small devices and accessories siamotainously.
If you want to run multiple air conditioning units, dual small generators with a parallel kit will not provide enough power. Most medium sized generator are also too small. If you need to run multiple AC’s, dual medium sized generators or a large generator are the only options.
3. Medium Size Generators
‘Medium size generators’ compete directly with ‘Dual Suitcase Generators’. Both styles offer similar power capability (in most cases ~2800 to 3600 running watts). Both styles are perfectly capable for most RVs. The main differences to consider are: size, weight, portability and price.
Medium size generators are typically cheaper, lighter, and less complex than two small generators with a parallel kit. However, the midsize generator isn’t always better for everyone. Choosing between the two really just comes down to deciding which you value more: portability and flexibility or simplicity and price.
Midsize Generator – Best Deal!
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There’s a lot of reasons why I love recommending this generator, but the primary reason is that it’s a ridiculously good deal, and a great value. With 4000 startup watts, and 3500 running watts, it has plenty of power for most RVs. Plus, you won’t believe how cheap this WEN 4000W open frame inverter generator is on Amazon. The WEN comes with a standard 2 year manufacturers limited warranty.
Exactly how good of a deal is it? Think about this: buying (2) Honda EU2200IC plus a parallel kit (Amazon) will set you back over $2,000. For that price, you can buy a WEN 4000W Inverter Generator and about 529 gallons of gasoline! That should be enough gas to last you – well, almost forever.
The WEN generator is 50% quieter, and 30% lighter than a standard generator (non inverter generator). Although it is said to be 50% quieter, it does produce 67 decibels, which is roughly 17% louder than most enclosed suitcase style small inverter generators. So if quietness is your #1 concern, you might want to pass on this unit. It has an average rating of 4.7/5 on Amazon, with lots of really positive reviews. If you’re interested in researching this generator further, you can read all of the Amazon reviews here.
Best Overall Midsize Generator (Electric Start + Dual-Fuel)
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If you’re looking for the best overall generator in its class based on price, value and features – I’m giving the nod to this CHAMPION dual-fuel 3400W inverter generator with electric start (Amazon). It’s extremely quiet (max 59 decibels) and it can run with propane from the built-in tanks on your RV!
I’m a huge fan of propane generators for camping because of the connivence they offer (running with fuel from the built-in RV propane tanks). I also love how they omit essentially no offensive exhaust smell whatsoever. To learn more about different generator fuel types and their advantages, see the section title ‘Generator Fuel Types’.
Dual Medium Size Generators With Parallel Kit
Many of the same advantages that dual suitcase generators provide, are also available with dual midsize units. However, applying the same parallel concept to these midsize generators gives you a 50-amp outlet and all the power necessary to run two air conditioning units!
This option gives you tons of flexibility when it comes to supplying your own ‘off-grid’ power to an RV for boondocking, or any time that electricity is unavailable.
When it comes to dual medium sized generators with a parallel kit, my recommendation is using two of the best-in-class Champion 3400W electric start, dual fuel, inverter generators (Amazon) paired together with the Champion 50A Parallel kiT (Amazon).
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- CHAMPION Dual-Fuel (Gas / Propane) 3400W Inverter Generator with electric start (Amazon)
- Champion 50A Parallel kit (Amazon)
4. Large Generators
When you need to run tons of stuff at the same time, including multiple air condition units, large generators are the only style with enough grunt. These generators are big, and have plenty of space to include a huge fuel tank. Because of this, they usually have excellent runtime.
Finding a generator with tons of power is easy – there’s plenty of options. The problem is, most large generators are extremely heavy, and loud. The real challenge is finding one with enough power, that is still portable enough, and quiet enough to enjoy your RV camping trips.
Quietest, Most Portable Large Generator:
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This Briggs & Stratton Q6500 QuietPower inverter generator offers an excellent combination of power, size, and weight. It uses a powerful motor, paired digital inverter technology to keep power and efficiency as high as possible, while minimizing weight and noise.
While the Briggs & Stratton Q6500 isn’t exactly small, or super light weight, it is 45% more compact, 30% lighter and 60% quieter than a standard 6500W generator. These improvements go a long way to make it an excellent option for powering large RV.
Generator Noise Output – Quietness (Decibels)
Choosing a quiet generator is important so that you can enjoy nature’s peace and quiet during a camping trip. If you have camp neighbors, they’ll appreciate the solitude also!
Generator noise is measured in decibels. On this scale of sound, 0 decibels represents total silence, 50 decibels is about as loud as a normal conversation, and 100 decibels is like a loud construction jackhammer. The scale goes over 100db, but trust me, you don’t want a generator that loud.
What is an Inverter Generator?
An inverter generator is a special type of generator that uses a digital inverter to convert mechanical power from a motor, into 120v electrical power.
Honda inverter generators are the gold standard of super-quiet portable generators. When Honda invented this special microprocessor controlled inverter generator technology, they changed the world (the world of generators, anyway).
This invention created an entirely new market segment, and Honda completely dominated it for many years before other brands started gaining market share.
Inverter generators are able to operate at lower engine RPMs when less power is needed while still producing a pure sine wave of 120v AC power. Because of this ability to produce usable power at lower engine RPMs, inverter generators are quieter, and more efficient than standard generators.
According to Honda Power Equipment, inverter generators have the following advantages:
- Higher quality power output
- Lighter, smaller size
- Higher fuel efficiency
- Quiet operation
- Parallel Capability
The Original Honda Inverter Generator:
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Although this is an updated version of the original, not much has changed. The Honda EU2000i barley registers on decibel scale. It only produces 48 decibels (low load) and a max of 57 decibels which is about as loud as a normal conversation.
Its definitely one of the quietest generators on the market, and according to some reviewers, it IS the #1 quietest generator! Honda also has a solid warranty, and reputation for quality, reliability, and efficiency.
The only downside to this Honda generator is that it’s more expensive than its competition. But my dad always told me, “you get what you pay for” – and with this Honda, you’re paying a little extra for a very high quality product.
A Cheaper Option That’s Still Super-Quiet:
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This WEN generator is less expensive and not quite as well know as some of the big names in power equipment like: Honda, Yamaha, and Briggs & Stratton. But don’t let that scare you.
The WEN56200i Super Quiet 2000-Watt portable inverter generator is one of the best selling, and most highly rated generators on Amazon. It has over 700 ratings with an average score of 4.3 out of 5 stars.
What Generator Fuel Type is Best? Gas, Propane, or Diesel
Gasoline powered generators are, by far, the most common type of portable generators. For most campers, a gas generator will work perfectly. However, propane and diesel powered generators both offer some unique advantages.
Propane Generators
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The main disadvantage to gasoline as a fuel source for RV generators is that it’s stinky (especially if it leaks or spills in your RV). Additionally, storing an extra can of gasoline is just one more thing taking up space.
Propane powered generators produce exhaust gasses that are nearly odorless and generally much less offensive than gasoline exhaust fumes. There’s nothing worse – in my opinion – than being in the great outdoors and being down wind of a gasoline generator that smells badly. Generator engines that running on propane are also cleaner, and produce less emissions!
In addition, the fuel for a propane generator can be supplied from built in propane tanks on an RV. Using the built in RV propane tanks for your generator fuel is convenient. It’s one less thing that you need to remember to bring on your camping trip.
Best All-Around Propane Generator:
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This midsize 3400 watt inverter generator made by Champion Power Equipment is extremely quiet, and has the ability to run on either propane, or gasoline. Check out the listing on Amazon, it’s an the Amazon Choice for generators, so you know its good!
It’s important to note that the power output capability is slightly lower when running on propane fuel. The generator has 3060 starting watts, and 2790 running watts while running on propane fuel.
Diesel Generators
Many diesel powered motorhomes have a built-in diesel powered generator. This is an awesome setup because the main motorhome engine, and the generator both draw fuel from one large fuel tank. The fuel tank can be filled up at a truck stop, or fueling station, and no 5 gallon portable gas/diesel cans are ever needed.
The main advantage of generator with a diesel engine is they are more efficient than a unit with a gasoline, or propane engine. Diesel engines typically have a longer service life and longer service intervals. In most cases, diesel engines are around 35% more fuel efficient than a similarly sized gasoline engine.
Built-in diesel powered generators are common in diesel pusher motorhomes – but portable diesel generators are rare, heavy, and expensive.
I generally do not recommend purchasing a diesel generator for recreational camping. Gasoline generators are way cheaper, and way lighter. However, there can be special circumstances where a diesel generator is the best option (or the only option if you only have access to diesel fuel).
Portable Diesel Generator:
In the image above: Generac (6864) 5000W Diesel Generator
This Generac XD5000E is one of the few available portable diesel generators. When it comes to demanding heavy-duty, high load usage, this diesel powered generator will easily beat any gasoline or propane generator at fuel consumption and efficiency. The main drawbacks are that it’s expensive compared gasoline generators, and weights a hefty 254 pounds.
Tips For Choosing A RV Generator
- Choose a quiet generator! You’ll thank yourself later.
- Portability and weight are more important than you might think. Having a generator that requires two people to lift can be a pain.
- Look into propane generators. Using the built in propane tanks for generator fuel can be extremely convenient.
- Make sure to buy a generator with a good warranty. You can get unlucky and have a problem, even the most expensive, highest rated generators.
- Use the generator sizing calculator near the top of this page to make sure you purchase a generator that is powerful enough to run your RV.
Frequently Asked Questions:
I’ve included some frequently asked question below as an additional resource for information on RV generators.
Can A Generator Run The 12V Power System In An RV?
Yes. When a generator is plugged into a RV, a built-in 120v to 12v power converter provides power to the 12v system and charges the RV batteries.
More Information on 12v and 120v RV Power Systems
RV’s use of two different types of power: 12v and 120v (12 volt and 120 volt). Nearly all of the the built-in appliances, light fixtures, and accessories in an RV use the 12v power system. This 12v system gets its juice (electricity) from one or multiple large batteries. Because the 12v power system uses battery power, you can continue using all the appliances and accessories without being plugged into external shore power (until the battery dies).
What is shore power?
120v electric power from an external source (like a campground hookup) is known as ‘shore power’. Shore power is a term originally used for ships getting power from the ‘shore’ while sitting docked. However, the term is also used with RVs, motorhomes and other land / air based vehicles like airplanes and trucks.
When a RV is plugged into 120v shore power, all the built-ins continue using 12v, but the system gets its power from a 120v to 12v electrical power converter (which also charges the battery).
Because of this, when calculating generator sizes, you can simply add everything up in watts, and not worry about 12v or 120v – it all needs to be included into the generator sizing calculation.
Thanks so much for reading along, and good luck with your RV generator purchasing! Do you have a favorite brand or style of generator that you think should be on this list? Let me know in the comments below.
