Portable Generator for RV Use: Power Requirements Explained

Choosing a portable generator for RV use is very different from choosing one for camping or basic outdoor activities.
An RV is not just a place to sleep—it is a mobile living space with a complex electrical system, and that complexity directly affects generator size, noise, and reliability.

Many RV owners discover too late that a generator “recommended online” cannot handle their setup, especially when air conditioning or battery charging is involved. This guide explains how RV power systems work, what drives generator wattage requirements, and how to size a generator correctly for real-world RV use.

If you are unsure how much power your RV actually needs, you can calculate your generator size based on real appliances, startup surge, and simultaneous loads:
→ Use the Generator Size Calculator

What Makes RV Power Needs Different?

RV electrical systems are designed to support continuous living, not occasional device charging. Compared to tent camping, RVs introduce:

  • Larger appliances
  • Multiple simultaneous loads
  • High startup surges
  • Long runtimes
  • Dedicated battery charging systems

As a result, RV generator requirements are often two to four times higher than typical camping setups.

Common RV Appliances and Power Demand

Most RVs include a mix of low-power and high-power appliances.

Typical Continuous Loads

  • Interior and exterior lighting
  • Refrigerator (12V, propane-assisted, or 120V)
  • Water pump
  • Fans and ventilation
  • Battery charger / converter

These loads are usually modest individually but add up over time, especially during extended use.

High-Power and Surge Loads

Certain RV appliances dramatically increase power demand:

  • Rooftop air conditioner
  • Microwave oven
  • Electric water heater
  • Coffee maker
  • Electric space heater

These appliances often draw large starting (surge) watts, even if their running wattage seems manageable.

Why Air Conditioners Change Everything

For RV generator sizing, air conditioning is the turning point.

A typical RV rooftop air conditioner may require:

  • 1,300–1,800 watts to run
  • 2,500–4,000+ watts briefly at startup

If your generator cannot handle this startup surge, the air conditioner may fail to start or repeatedly trip overload protection—even if the generator appears powerful enough on paper.

Not sure whether your RV air conditioner will start reliably?
Use a generator wattage calculator to account for both running watts and startup surge based on your actual RV setup.
→ Calculate your RV generator size

This is the single most common reason RV generators are undersized.

RV air conditioners are one of the most common sources of startup surge. If you are unsure how surge power differs from normal usage, see:
→ Running Watts vs Starting Watts Explained

30 Amp vs 50 Amp RV Electrical Systems

Understanding your RV’s electrical system is essential before choosing a generator.

30 Amp RV Systems

  • Single 120V line
  • Theoretical maximum: ~3,600 watts
  • Common on smaller RVs and travel trailers

Even with a 30A system, you rarely want to operate at maximum capacity continuously.

50 Amp RV Systems

  • Two separate 120V lines
  • Much higher total available power
  • Common on larger RVs and motorhomes

A 50A RV does not always use full capacity, but it allows more appliances to run simultaneously—significantly increasing generator requirements.

Is a 6500 Watt Generator Enough for RV Use?

For most 30-amp RVs, a 6500 watt generator is more than enough to power typical onboard appliances, including one air conditioner.

A 6500W generator can usually run an RV air conditioner, microwave (not at the same time as heavy loads), refrigerator, battery charger, lights, and outlets. It also provides enough headroom to handle AC startup surges.

However, for 50-amp RVs, a 6500 watt generator is generally not sufficient to run multiple air conditioners or high-demand appliances simultaneously.

If your RV setup varies, use a wattage calculator to verify your actual running load and starting surge before choosing a generator.

Battery Charging and Converters: The Hidden Load

RV generators do more than power appliances—they also charge onboard batteries.

The converter/charger can:

  • Draw substantial power during bulk charging
  • Operate simultaneously with other loads
  • Increase total demand unexpectedly

Many RV owners underestimate generator size by ignoring battery charging loads entirely.

Why “Rules of Thumb” Often Fail for RVs

You may hear advice like:

  • “A 2000W generator is enough for most RVs”
  • “Just double your camping generator”

These shortcuts ignore critical variables:

  • Air conditioner startup surge
  • Number of appliances running together
  • Battery charging behavior
  • Individual RV electrical layouts

Every RV is different.
Instead of relying on rules of thumb, calculate your actual running and starting watts based on the appliances you use.
→ Use the RV generator wattage calculator

Two RVs that look similar can have dramatically different power needs.

How to Size a Generator for RV Use Correctly

The most reliable approach is to calculate:

  1. Total running watts of all devices you may use simultaneously
  2. Largest single starting surge
  3. A reasonable safety margin for real-world conditions

Instead of guessing, use a generator wattage calculator to model your actual RV setup—including air conditioner startup, battery charging, and simultaneous loads.

→ Calculate your RV generator wattage

Noise and Runtime Considerations for RV Generators

While RV environments are generally more tolerant of noise than campgrounds, quiet operation still matters:

  • Long runtimes amplify fatigue from constant noise
  • Nighttime use increases perceived loudness
  • Efficient, low-load operation reduces both noise and fuel consumption

A properly sized generator often runs quieter and longer than an undersized one pushed to its limits.

Common RV Generator Mistakes

  • Choosing based only on advertised wattage
  • Ignoring air conditioner startup load
  • Forgetting battery charging demand
  • Oversizing without understanding load behavior
  • Assuming all RVs have similar power needs

Most of these issues stem from incomplete load calculations.

Conclusion

RV generator selection is not about finding a “big enough” model—it is about understanding how your RV actually uses power.

By accounting for air conditioner startup, simultaneous loads, battery charging, and real-world usage patterns, you can choose a generator that delivers reliable power without unnecessary noise or fuel waste.

Ready to size your RV generator with confidence?
Calculate your real running watts and startup surge to avoid overloads, excessive noise, and wasted fuel.
→ Try the generator size calculator

To continue planning your RV power setup, explore these resources: