What is the Safe Runtime Duration for an RV Generator?

An RV generator is a great piece of equipment to have. It might not be that important when shore power is available at the campsite, but it becomes a necessity when you are boondocking or tailgating. 

Sometimes a need for power will be for more than a day or two. A generator can run continuously for that period with enough fuel, but is it safe to do so?

The runtime of an RV generator will be determined by the load it supplies at any given moment, the size of a fuel tank, the type of fuel, and the model of a generator.

If you are wondering how long you can run an RV generator uninterrupted, then this article will provide the answer. And also share a few tips to improve fuel consumption. 

An average continuous runtime for any RV generator, whether it is portable or built-in, will range from 8 to 20 hours; there are exceptions too. In this article, we will also see top RV generators and how long they can run.

How Long a Portable Generator Can Operate?

As we have mentioned, the runtime of a generator depends on many things. Most portable generators use either gasoline or propane as fuel. When it comes to efficiency, propane is much more efficient than gasoline but will generate less power than a gasoline-powered generator can.

For a gasoline generator, the continuous runtime mainly depends on the size of a gas tank. How long it will run before it needs refueling will be a prominent factor in deciding the continuous runtime. 

For propane, the deciding factor is the size of a propane tank; there will be no tank on the unit; they are available separately and in various sizes. The bigger propane tank will have increased continuous runtime. Also note, this will be limited by other considerations as well and not only by propane tank size.

Someone might now argue that we can increase the runtime if gasoline is poured while the generator stays running. But that is not safe, not safe at all. 

A running generator is hot, which may lead to the ignition of gasoline fumes which may result in fire or explosion. On top of that, the gas may expand, which risks overflowing over the hot engine. So, don’t do that; let it cool down before refueling.

The fuel tank size for a portable generator can range anywhere from 1 to 10 gallons, and its wattage will decide the rate of fuel consumption and ascertains how long the fuel will last. 

When these two things are combined with the type of fuel and the power needed, you will have your uninterrupted runtime.

And at last, all these things conclude to a general result of 10 to 13 hours of continuous use, without the need to refuel.

How Long a Built-In Generator Can Operate?

The built-in generators are the same as the portable ones. The major difference between them is their power rating and the fuel tank. They will generally have a power rating from 2000 watts to 6000 watts. 

As long as the fuel tank is concerned, they don’t have one on the generator itself, and there will be a separate fuel tank to store the gasoline from where it will travel to the engine through a pipe, or there may be a direct connection from the main gas tank of your motorhome. For propane, there will be a separate tank as well.

The size of the fuel tank for a built-in generator can range from 6 gallons to as large as one with 60 gallons of capacity. Suppose you have a generator with a power rating of 4000 – watts, and it is running at its full capacity; everything it can power is on. In this state, it will consume roughly 1 gallon of fuel per hour.

The same goes with the propane because a 30-pound tank can store about 7 gallons of propane which provides the runtime of 7 to 8 hours before it needs to be replaced. 

If the tank is bigger, then you will get increased runtime. So, in conclusion, no matter the type of fuel a 4000-watt unit uses, it will consume 1 gallon of fuel per hour.

So, your continuous runtime will be decided by how big a fuel tank you have. For this as well, you can’t refuel the gas or replace the propane tank when the generator is running.

Other than that, certain campgrounds will let you run your generator for a specific period only, and this may limit the continuous runtime, which has nothing to do with the generator specification.

How to Improve Fuel Consumption?

Improved fuel consumption will result in longer runtimes. By doing some simple things, you can increase the runtime of your generator.

When running your air conditioner unit, you should keep the windows and the doors closed. With this, the temperature will be maintained for longer. 

This will lead to an increase in the time intervals between consecutive sessions as AC operates when the temperature falls below a certain limit.

Moreover, you can replace your lights with LED lights; they are more efficient and require very little power to run. Proper and regular maintenance can also increase the runtime of a generator.

Runtimes of Different Generators

In this section, we have listed down the five best RV generators, their runtime, and the fuel tank size.

1. The Briggs and Stratton P2200 Power Smart Inverter Generator

  • Fuel – Gasoline
  • Runtime – 4 hours on half load
  • Tank Size – 1 gallon

2. WEN 56200i 2000-Watt Gas Powered Inverter Generator

  • Fuel – Gasoline
  • Runtime – 6 hours on half load
  • Tank Size – 1 gallon.

3. The DuroStar DS4000S Portable Generator

  • Fuel – Gasoline
  • Runtime – 8 hours on full load
  • Tank Size – 4 gallons

4. Generac GP2500 Inverter Generator

  • Fuel – Gasoline
  • Runtime – 4 hours on half load
  • Tank size – 1 gallons

5. Champion 3400-Watt Dual Fuel RV Ready Inverter Generator

  • Fuel – Gasoline, Propane
  • Runtime – 7.5 hours on gasoline and 14.5 hours on propane
  • Tank size – 1.6 gallons


Whether it is a portable generator or a built-in generator that you use for your RV, the continuous runtime will be limited by many factors, which we have discussed in detail. 

The brand, model, and maintenance of the generator are also the deciding factors for its runtime.

Now the question, is it safe for a generator to run continuously for days? 

The answer is yes. If you need power for more than a few days, then you better have a standby generator because they have better and more robust components; a portable generator is simply not designed to handle that much continuous run.