What size generator do I need to power an RV?

What size generator do I need to power an RV?

Stainless steel refrigerators, microwave ovens, and air conditioners (ACs); modern recreational vehicles (RVs) are truly home away from home. In fact, some of the large and luxurious RVs feature RV generators that are more powerful than the back-up power generator you might be using at your home. 

You might feel overwhelmed as you try to find the right size generator to power your RV. There are lots of options in the market and terminology around watts, amperages and volts. Meanwhile, there are simple methods you can use to narrow your options. In this article, you will find the answers to common generator sizing questions. If you are new to RV generators, check out RV generator basics for an intro.

What size generator do I need for my RV?

While the size of the generator you need depends on specific equipment you have within the RV, below is some high-level guidance. 

Generator sizes for different RVs
  • Class B Van with one AC unit: 2,000 to 3,600 watts
  • Class C RV with one AC unit: 2,800 to 4,000 watts
  • Class A RV with two AC units (15,000 BTU each): 5,500 to 8,000 watts
  • Class A RV with three AC units (15,000 BTU each): 10,000 to 12,500 watts
  • Fifth wheel with two AC units: 5,500 to 7,000 watts 

Please keep in mind, these ranges could change based on your specific equipment. 

Let’s take a more detailed look at the equipment within your RV, which will help identify the generator size you need. 

The first consideration is the electrical power needed by each appliance and device. Here is a list of common appliances and the amount of electricity they each need. 

Electricity consumed by RV appliances
  • AC units are often the appliance that requires the most power in an RV. AC units 13,500 to 15,000 BTU need between 1,200 and 2,400 watts of electricity to run. If you have multiple AC units, you can multiply the wattage needed accordingly.
  • Dishwasher: 1,200 to 2,400 watts 
  • Stove: 900 to 2,500 watts
  • Hair dryer: 1,200 to 1,875 watts
  • Clothes iron: 1,000 to 1,800 watts
  • Washer: 1,000 to 1,500 watts
  • Coffee maker: 900 to 1,200 watts 
  • Microwave: 750 to 1,500 watts 
  • Toaster: 800 to 1,400 watts 
  • Refrigerator: 400 to 1,000 watts
  • Blender: 450 to 700 watts 
  • TV: 43 to 600 watts 
  • Radio: 50 to 200 watts
  • Gaming console: 70 to 180 watts 
  • Laptop: 20 to 50 watts 

Please note that some appliances have large compressors and motors. These could require higher wattage when they start.

The second consideration is looking at the usage pattern for the appliances and devices. For example, you would likely not operate all these appliances at the same time. In addition, some appliances like refrigerators will run more frequently than others, like toasters. 

The final consideration is the difference between starting and running power. Some appliances need more power for a short time at the beginning of their operation. For example, AC units would draw much more power when they first start. 

What is the difference between 30-amp and 50-amp RV?

Let’s start with the basics. Electricity is simply the flow of electrons. You can read more about it in our article explaining the difference between electricity and energy. Amperage is the volume of electrons that flow, and a higher amperage means more electrons flowing and consequently more electricity. 

Thirty amp and 50-amp are the two most common electrical service capacities used within RVs. A 50-amp service can handle more electric power than a 30-amp service; this is because a 50-amp service can handle a higher volume of electrons. When you multiply amperage with voltage, you find the electrical power. Most electrical equipment in RVs operate at 120 volts, independent of 30-amp or 50-amp service. 

To find how many watts of power you have available, you need to multiply volts times amps. For example, a 30-amp RV with a 120 V electrical source would be capable of handling about 120 x 30 or 3,600 watts of electric power. 

What size generator do I need for a 30-amp RV?

An RV with a 30-amp shore power connection and with 120 V equipment would be capable of handling a maximum of about 3,600 watts of electric power. This means a 3,600-watt generator would give you the same amount of power as shore power. Meanwhile, you can also get a 4,000-watt generator for these coaches to give additional electrical motor-starting power. 

A 2,500-2,800-watt generator is often a good minimum threshold for 30-amp RVs that have AC units. 

What size generator do I need for a 50-amp RV?

An RV with a 50-amp shore power connection typically has two separate 50-amp feeds. This is different than a 30-amp RV with only one 30-amp feed. A 50-amp RV with a 120 V electrical feed is capable of handling 12,000 watts of electric power. This means a 12,000 or 12,500-watt generator could be your top end choice.

You can also get a better sense of the generator you need using the bullet points in the first section of this article, under “What size generator do I need for my RV” header.

Now that you have a better idea on the generator size you need, don’t forget to check how to find a quiet generator for your RV.

Get the most out of your RV! Sign-up below to receive periodic tips and insights any RVer would enjoy . 

Aytek Yuksel - Cummins Inc

Aytek Yuksel

Aytek Yuksel is the Content Marketing Leader for Cummins Inc., with a focus on Power Systems markets. Aytek joined the Company in 2008. Since then, he has worked in several marketing roles and now brings you the learnings from our key markets ranging from industrial to residential markets. Aytek lives in Minneapolis, Minnesota with his wife and two kids.

Why I sell Cummins generators for hurricane season

Cummins generator powering a home in the rain

This article was authored by Jared Godwin, Cummins dealer at Lawson & Lawson Electrical Services

Years ago, the electrical contractor I work for, Lawson & Lawson in Tallahassee, began selling home generators because we wanted to help our customers power through anything. This is Florida after all, and hurricanes are a constant risk.

How Hurricanes Create Power Outages.

Year after year, we see the damage hurricanes cause. Some of the worst wreckage we’ve ever seen was in 2018 when we opened our Panama Beach office. Hurricane Michael, a category 5, had just hit nearby Mexico Beach.

Destructive storm wind and rain are hard on Florida’s trees, causing limbs to fall on power lines and leaving Floridians without power. Eventually my customers become tired of sitting in the heat and waiting for the power to be turned back on. So, they decide to get a Cummins QuietConnect™ standby generator for their homes. The most common phrase I hear from them is, “I just can’t go another year.”

The Importance of Ordering a Generator Early.

If you’re interested in a home standby generator, don’t wait. Schedule an appointment with your authorized Cummins dealer as soon as possible. Here in Tallahassee, it takes a month to get a permit and up to another two weeks to schedule and install the generator.

Six weeks on the high side is not a big deal for somebody who has already made the decision. But for someone panicked because they see a hurricane out in the Gulf, there’s simply not enough time before the storm makes landfall.

In other areas of the country, permitting times may vary, so it is always best to be prepared. You can find a local Cummins dealer or schedule a free in-home assessment through the Cummins website to get started.

Why We Sell Cummins Generators.

The answer is simple. The Cummins makes quality products and stands behind them. We know if there’s an issue, Cummins is going to work with us to quickly resolve it. That keeps our customers happy and gives us the confidence to recommend its whole-home generators.

When we install our Cummins QuietConnect standby generators, we work with a lot of gas contractors. As they connect their gas lines to the generators, they see just how well they work and are impressed. So, we also get a lot of referrals through them.

Creating a good customer relationship is important to us. I give my customers my mobile phone number and answer texts 24/7 throughout the installation process. This gives them the peace of mind of knowing they are going to be taken care of by me and by Cummins.

At the end of the day, when you sell a good product and do a good deed, it gets around. If you’re interested in becoming a Cummins dealer like Lawson & Lawson, check out the benefits of partnering with Cummins.

Cummins Office Building

Cummins Inc.

Cummins is a global power leader that designs, manufactures, sells and services diesel and alternative fuel engines from 2.8 to 95 liters, diesel and alternative-fueled electrical generator sets from 2.5 to 3,500 kW, as well as related components and technology. Cummins serves its customers through its network of 600 company-owned and independent distributor facilities and more than 7,200 dealer locations in over 190 countries and territories.

What’s the true cost of a power outage without a Cummins home generator?

Home during power outage

Long-term power outages can be both inconvenient and expensive, disrupting your family’s comfort and safety. While every power outage is different for each homeowner, costs can add up to a surprisingly large amount. Plus, if you work from home or have a home business, in addition to any physical damages, you may have to endure the cost of lost work, productivity or wages.

Before you invest in a Cummins QuietConnect™ home standby generator, first consider the cost of going through a major power outage without one. Then, compare that cost against the price of a Cummins standby generator. You can get an estimate on a whole house generator by finding a dealer with our dealer locator tool, or by requesting an in-home assessment.

Whether your power outages are caused by severe weather, an aging power grid or rolling brownouts, here are some of the financial hits your family may have to absorb:

  • Flooded basement — If the electricity goes out and your sump pumps stop working, you may wind up with water damage in your basement. According to homeadvisor.com, the average cost to clean up a flooded basement could range between $500 and a whopping $85,000.
  • Mold remediation — Enduring some flooding means you will likely need to have portions of your home treated to prevent toxic mold. The experts at bobvila.com say the average cost of mold remediation is $2,214.
  • Food spoilage — If the power stays out for enough time, the food in your refrigerators and freezers will spoil. Forbes.com says that many insurance companies will pay up to $500 worth of food spoilage, but only if the cause of the power outage is covered under your policy. If you have a full deep freezer full of meat, the costs could be even more.
  • Burst or frozen pipes — Losing power during the winter months brings additional risks. According to Consumer Reports, the cost to repair burst or frozen pipes can easily exceed $5,000.
  • Hotel stays — If your home becomes uninhabitable during a power outage, your family may need to seek alternate shelter. Statista, which tracks hotel prices, says the average nightly stay costs $90.92. Add in the expenses of travel and meals out and the number begins to rapidly climb.

There are additional costs to consider as well — not all of them financial. For instance, there’s the impact to your health if you use home medical devices and the inconvenience of having your life turned upside down during the power outage.

With power outages becoming more and more common, it’s easy to see how the hidden financial and quality-of-life costs escalate, putting the cost of a Cummins QuietConnect home standby generator in perspective.

To find a dealer to help you estimate the investment needed for your own home generator, please visit our home generators dealer locator map.

Cummins Office Building

Cummins Inc.

Cummins is a global power leader that designs, manufactures, sells and services diesel and alternative fuel engines from 2.8 to 95 liters, diesel and alternative-fueled electrical generator sets from 2.5 to 3,500 kW, as well as related components and technology. Cummins serves its customers through its network of 600 company-owned and independent distributor facilities and more than 7,200 dealer locations in over 190 countries and territories.

Watch Now: What Consulting-Specifying Engineers need today

Wissam Balashe with the Editor in Chief, CSE Magazine - Amara Rozgus

Watch Cummins Business Director for Energy Management Solutions, Wissam Balashe's interview with the Editor in Chief, CSE Magazine - Amara Rozgus here. In this insightful conversation, Balashe discusses what Consulting-Specifying Engineer’s (CSE) are requesting OEM manufactures for while designing energy solutions. He spoke in depth about the work done by Cummins Power Generation to meet these needs. 

He further talks about the shift towards an integrated power solution approach and the considerations electrical engineers should take while designing or retrofitting existing controls systems. He used his industry knowledge to discuss the steps that CSE’s can take to keep up with the emerging technologies in the dynamic power generation industry.


Wissam Balshe

Wissam Balshe

Wissam Balshe has been in the power systems industry since 2002 and joined Cummins in 2007. He led the application engineering team for North America (2007-2010), then led the Strategic Business Development efforts for the Power Solutions Business (2011-2015), focusing on Distributed Generation and Micro-grid applications. He joined the North America Power Gen Sales team managing the Rocky Mountain Territory for a brief period in 2016 before joining the Marketing Segment team as the director of the Mission Critical Segment. Wissam currently leads the Global Systems & Controls Business for the Power Systems Business Unit.   

Wissam represented Cummins in multiple codes and standards committees (IEE1547, CSA282, NEMA MG1), and trade associations (Vice Chair of the US CHP Association in 2012-2013). He actively advocates distributed generation incentives at the Federal and State Levels and the board of multiple community organizations in Minnesota (outside of Cummins). 

Wissam has a Bachelor’s degree in electrical engineering from the University of Minnesota, and an executive MBA from Indiana University.

Should you choose a whole-home standby or portable generator?

With the increased frequency of severe weather events, you may find yourself considering a home backup generator. What type is best for protecting your family during weather-related outages? The answer: It depends. 

Cummins whole-home standby generators and portable generators have different advantages. To help you decide which one is right for you, here are four things to consider:

Power everything or just a few essentials?

If you want to power your whole home and carry on as if nothing has happened outside, then a Cummins QuietConnect™ standby generator is the way to go. This permanently installed generator will be strong enough to run all or nearly all the devices in your home. With a portable generator, you will have to size the generator set to power only certain essential devices. 

What’s your budget?

Standby generators are more powerful, longer lasting and less work to use, but they are also more expensive. Portables are more affordable because they are less powerful and more labor-intensive to use.

Permanent installation or portability?

One of the advantages of portables is that you can use them for more than just powering essentials in your home. You can take them with you on camping trips, tailgates or to power tools on worksites. Standby generators are permanently installed at your home.

How much work do you want to do?

With a standby generator, you often don’t have to lift a finger. An automatic transfer switch is part of the installation. In a power outage, the switch will automatically detect the power outage, disconnects your home from the utility line and connects it to the generator. Once electric service has been restored, it will reverse the process. 

With a portable generator, you have to get it out of storage, wheel it a safe distance from the house, fill it with fuel, start it and then run a power cord from it to the house…often in bad weather. If your outage lasts a long time, you will have to periodically refuel it. Then, after the outage, you have to disconnect it from your appliances, drain the fuel and wheel it back to storage.

There are other differences to consider before purchasing a home standby or portable generator. Your friendly Cummins dealer will be happy to walk through all of them with you. 

To get connected with a Cummins authorized dealer, visit our find a dealer page. You may also want to use our generator sizing calculator to get a rough estimate of how much power you need. 

Cummins Office Building

Cummins Inc.

Cummins is a global power leader that designs, manufactures, sells and services diesel and alternative fuel engines from 2.8 to 95 liters, diesel and alternative-fueled electrical generator sets from 2.5 to 3,500 kW, as well as related components and technology. Cummins serves its customers through its network of 600 company-owned and independent distributor facilities and more than 7,200 dealer locations in over 190 countries and territories.

Redirecting to

The information you are looking for is on

We are launching that site for you now.

Thank you.