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What Size Propane Tank for Generator? (Explained)

Generators are one of the useful machines that can come in handy in many different situations. The important thing to remember here is that generators rely upon several parts for their functions and mechanisms. One of those parts is a propane tank. 

Today, we are going to discuss different types of generators and find out what size propane tank is needed for each one. 

Propane tank size for generator:

The basic requirement of operating a generator is finding the right size propane tank. A whole house standby generator might require an 100/250/500 gallon propane tank for its higher fuel consumption. But a portable generator can be operated with the help of a 20/30/40/100 lb propane tank.

There are many types of generators available in the market. Let’s take a look at some of them and see what size propane tank is required. 

Whole house standby generator:

A whole house standby generator is known for bringing many benefits to the table. First of all, we need to remember here that a whole house standby generator got its name due to the ability it possesses to power up your entire house during load shedding. 

Whole house standby generators are different from other types of generators as they are able to generate much more power for a prolonged time. It might cost you a lot to buy a whole house standby generator. But it would be worth it in the long run. 

Propane tank is a key part of how a whole house standby generator operates. It is important to choose a right size propane tank for your whole house standby generator. There are a lot of things that can influence this decision. 

However, it is believed by experts that you can choose a one hundred gallon/two hundred and fifty gallon/five hundred gallon propane tank for your whole house standby generator. 

A one hundred gallon propane tank will be able to serve the whole house standby generator for two days. On the other hand, a two hundred and fifty gallon propane tank will be good for about five days or so. 

Additionally, your whole house standby generator will function for about ten days on a five hundred gallon propane tank. You can select any one of these propane tanks based on the needs of your whole house standby generator.

Portable generator:

The portable generators are not as mighty as the whole house standby generators. But they can certainly step and power up your house when load shedding takes place. Additionally, buying a portable generator will not cost much.

Selecting the right size propane tank for your portable generator is important for how it functions. Most of the experts believe that a twenty lb propane tank will be more than capable of supporting your portable generator. 

Other experts believe that you can even opt for a thirty lb or a forty lb propane tank for your portable generator. 

Things to consider before choosing propane tank size for your generator:

There are many things that you need to consider before choosing propane tank size for your generator. Let’s discuss in detail about some of them.

The type of generator:

The first thing you need to consider is the type of generator you are dealing with here. First of all, the mechanisms and functions of a whole house standby generator differ from a portable generator. 

You will need to choose a bigger size propane tank for your whole house standby generator. Because portable ones do not generate as much power as the standby ones and can function with a smaller size propane tank. 

Recommendation of manufacturer:

The manufacturer’s guide that comes along with your generator will have for you the needed instructions to select the right propane tank size. It will contain the details on the amount of fuel consumption done by your generator. 

You can use this information to find a suitable propane tank for your generator. 

The amount of load shedding:

The amount of load shedding that takes place in your area can also determine the propane tank size. Because a higher amount of load shedding will mean a higher amount of fuel consumption on the part of your generator. 

So you will need to use a bigger size propane tank for your generator if there is frequent load shedding in your locality. 

The state of propane:

One great thing about propane is its incredibly longevity. It can stay good for a long period of time without losing its quality. It means you can opt for a bigger size propane tank for your generator without having to worry about the state of propane.

It can be an important factor when it comes to selecting a propane tank size for the generator. 

The total cost:

You will also have to consider the total cost of buying and installing a propane tank. A bigger size propane tank will usually cost you a lot more than a smaller size propane tank. 

So if you are really worried about the total cost, then you can certainly opt for a smaller size propane tank for your generator. 

The quality of the generator:

The quality of the generator can also determine the propane tank size. A high quality generator will be able to produce more power than a low quality. So you will be required to select a bigger size propane tank for a high quality generator. 

The quality of the propane tank:

The quality of the propane tank is another deciding factor when it comes to the propane tank size for a generator. 

The expansion of the propane tank, the contraction of the propane tank, the weight of the propane tank, the horsepower of the propane tank – all of these factors influence the decision of choosing a propane size for your generator.  

The house’s power consumption:

Ultimately, the purpose of using a generator is to provide backup for the electrical requirements of your house. The higher the power consumption of your house, the higher the need for a bigger size propane tank. 

Because a generator is dependent upon the propane gas to produce power for your house in case of load shedding.

Let’s have a look at different sizes of generators in the chart below and find out the perfect propane tank size for them.

GeneratorPropane Tank Size
10 kW generator20 lb
15 kW generator30 lb
20 kW generator100 gallon
22 kW generator120 gallon
25 kW generator250 gallon
30 kW generator500 gallon

Importance of picking the right size propane tank for your generator:

The generator of your house needs a decent amount of propane gas for its functions. So it is very important that you select the right size propane tank for your generator. Without the right size propane tank, your generator will face difficulties to perform its actions. 

As a result, your house can face a lack of backup power in case of load shedding. 

A wrong size propane tank can even hamper the state of your generator in the long run. A right propane tank is key for a fully functional generator. 

How long can a propane tank run a generator?

Let’s take a look at different sizes of propane tanks and see how long a propane tank can run a generator.

20 lb propane tank:

A 20 lb propane tank is fairly small in size. It is believed by experts that a 20 lb propane tank can support the generator for five hours only. 

30 lb propane tank:

According to experts, a 30 lb propane tank can provide support to the generator for eight hours only. This time limit can get influenced by the fuel consumption of the generator.

40 lb propane tank:

A 40 lb propane tank can help the generator power up for ten hours at the very least. It can vary depending on the type of generator.

100 lb propane tank:

On an average, a 100 lb propane tank can provide support to a generator for about fifty hours. This can increase or decrease depending on the generator’s fuel consumption ratio. 

100 gallon propane tank:

It is believed by experts that a 100 gallon propane tank will be good enough for two days when it comes to powering up your generator. 

250 gallon propane tank:

A 250 gallon propane tank will support a generator for about five days. However, the backup can be cut less if your generator has the tendency to consume more fuel than an average generator. 

500 gallon propane tank:

It is believed by experts that a 500 gallon propane tank can support your generator for no more than ten days. 

Final Thoughts

The fuel consumption of a generator can determine the size of the propane tank needed to run it. It is difficult to see past the importance of selecting the right size propane tank for the generator. The longevity of propane gas provides the option of choosing a bigger size propane tank.