How Long Does Propane Last in an RV?

Propane is particularly important for most RVs as it acts as a fuel source for it. It then becomes important to accurately plan out your RVs propane usage for more efficient use. If you don’t have much of an idea about the lasting capacity of a propane tank, you will find this article useful. We have carefully detailed the process of calculation, which you can also use to find out the life of your propane tank.

What Are the Standard RV Propane Tank Sizes?

Propane tank sizes can be varied and you can select them according to your requirements and preferences. You will find when looking at a propane tank cylinder that the manufacturer has listed the size in terms of pounds and/or gallons:

The measurements in pounds will actually indicate the total weight of the cylinder when full. The gallon measurements will tell you exactly how much propane will fit inside the tank. We would recommend you concentrate on the pound measurement when you buy a tank for your RV.  At the same time, knowing the gallons in your tank will help you calculate your propane usage. We will describe the process in the last section.

(Please note that a “full” propane tank is only at 80% capacity. The other 20% is the space required for the liquid propane to expand.)

If you look at the majority of purchases that have been made, there are two most common propane tank sizes for RVs. These sizes are:

• 20 pounds

A smaller option needs to be refilled frequently. It is suitable for people who do not like to waste fuel. It has a capacity of 4.6 gallons when full.

• 30 pounds

This option holds more propane and will last longer. It would also need less frequent refilling. It comes at 7 gallons when full. However, it is still quite portable for a single person.

The other options available are 11 pounds, 40 pounds, and 100-pound.

It is possible that sometimes a single tank will not be able to fulfill your requirements. In this case, a second tank, carrying backup tanks, or jumping up a tank size can be beneficial.

How Long Does Propane Last in an RV?

It is not very easy to determine exactly how long a propane tank will last for your RV. This depends on several factors, including the fact that propane is not the only fuel source for RVs.

Most of your RV’s energy use will come from electric power. However, this won’t be enough alone, and so you will see that several appliances on the RV will operate on propane.

To know exactly how long the propane tank will last, you need to consider the following factors:

• Propane tank size
• Frequency of appliance use
• The BTU rating of your propane-powered appliances
• BTUs (British thermal units) 

A thorough knowledge of BTU is not necessary for estimating your propane usage. All you need to know is the BTU rating of each appliance which will be propane-powered in your RV and that:

• One gallon of propane has 91,502 BTUs
• One pound of propane has 21,548 BTUs

With this information, it will be easy to find the total BTUs in your tank through multiplication. Once you are done calculating the total BTU capacity of your propane tank, you’ll need to divide the total by the BTU usage for each dependent appliance in your RV.

Here is a simplistic view:-

Propane gallons X 91,502 = Tank BTUs

Tank BTUs divided by total appliance BTU usage = hours of propane use.

How Long Will a 20 LB Propane Tank Last in an RV?

If you have a full 20 lb. tank, it will also have 4.6 gallons capacity. First, you have to multiply 4.6 by 91,502. You will get 420,909. Then divide that number by the total BTU usage of the appliances, which we calculated before to be 40,000 BTUs.

When you divide 420,909 by 40,000, the answer comes to 10.5. This means that you can use your appliances for about 10.5 hours before your tank runs out of propane.

How Long Will a 30 LB Propane Tank Last in an RV?

If you have 30 lb. propane tank capacity, it will also have a capacity of 7 gallons when full. In this case, we have to multiply 7 by 91,502 to get 640,514. Then you have to divide that figure by the 40,000 BTUs of appliance usage.

The answer you will get is 16. This means that a 30 lb. propane tank will be able to run your appliances for about 16 hours before its tank runs out.

How Long Will A 40 LB Tank Last in an RV?

In case of a 40lb propane tank, the gallon capacity will be 9.4. So you have to multiply 91,502 by 9.4 gallons first. The result will be 860,119. Now you can follow the above example and divide that figure by the 40,000 BTUs of appliance usage.

You will get the answer 21.5. This means that a 40 lb. propane tank will be able to run the appliances for 21.5 hours before the tank runs out.

How To Make RV Propane Last Longer?

If you use this fuel wisely, propane is going to save you a ton of money on energy costs. To help you with efficient use of propane, we have prepared some points that you should remember when using propane:-

• Add more insulation 

The heat from a propane tank will be most effective when your RV has the proper insulation. You can add extra insulation to doors and windows. 

• Use the appliances wisely

Using appliances wisely will help you manage propane use. Don’t use appliances for a prolonged time for no reason.

• Use a propane regulator

A propane regulator will help to regulate the amount of pressure released from the propane tank. It will make sure that the supply of propane to your appliances is the right amount.