Propane vs Gas Generator (Which One Is Better)

A portable generator is a great source of emergency backup power for power outages, for instance when natural disaster strikes. You can also use portable generators for camping, other recreational activities, or any projects where you need but do not have access to electricity. The traditional choices of fuel for generators are gasoline and diesel, but propane has made its way onto the scene.

Propane combustion is very similar to that of gasoline, and both fuels can use the same carburetor. Increasingly, you will find engines that can accommodate either gasoline or propane, which has only fueled (excuse the pun) the propane vs gas generator debate.

Despite commonalities, these fuels have distinct advantages and a few drawbacks. The best fuel option will depend on how you want to use it and how much power you’ll need.

The information below compares the differences between propane and gas generators. It will help you determine which one is right for you.

Gas vs. Propane Generators

Gasoline is a liquid produced from refined petroleum used to fuel combustion engines. It is the most used fuel in the world.

Propane is a liquefied petroleum gas stored inside a compressed tank. It converts to a gas as it releases from pressure.

Are There Differences in Gas and Propane Supply?

You can find gas stations almost anywhere. Propane is widely available as well, but you may not be able to find it in near where you live.

Also, while you can buy propane containers at a variety of stores, it is more cost-effective to have them refilled than to replace the entire tank. This may be less or more of an issue depending on how much propane you use. If you are a business that relies on generators every day, the ability to refill tanks may be a major consideration.

Which Fuel Is Better for the Environment?

When comparing propane generators vs gas generators, environmental impact is an important factor. Propane is much more clean burning than gasoline. According to the National Propane Gas Association, propane releases much less carbon dioxide, carbon monoxide, nitrogen oxide, and hydrocarbons than any other fossil fuel.

Because it burns cleaner, propane will not leave residue in your carburetor or spark plugs. It is less toxic for human beings as well. Unlike gasoline, propane tanks emit no toxic fumes when in storage.

How Long Can You Store Each Fuel?

Backup generators are not much use without having a fuel source on hand. So you’ll be needing to store either gas cans or propane tanks.

One issue where propane generators are the clear winner — and can offset availability issues — is shelf life. Unlike gasoline, you can store it as long as you want, and it will not expire or diminish in energy concentration over time.

Gasoline only lasts between three months and about a year (if you add stabilizers to your gas tank) before it begins to deteriorate. As it does so it becomes denser and can clog lines, gum up the generator engine, and damage components. For this reason you should occasionally either drain gas generators or run them until the tank is empty. So using propane makes generator maintenance a bit simpler.

Since it attracts water molecules in the air, the presence of ethanol can shorten the life of gas further.

One other storage issue is volatility near flames. Gasoline is highly flammable. Propane gas is as well but, stored in its liquid form, it will not combust.

One downside to propane storage is that, since the gas is invisible and has no smell, a propane tank leak can be difficult to detect. Manufacturers must add a scent to the propane; but, in gas form, it is denser than air. It will sink to the lowest point in a space, so it may go undetected by someone walking through a room.

Speaking of safety, you may want to learn how to ground a generator.

What About Ease of Use?

Unlike propane engines, where the storage tank connects directly to the machine, you must transfer gasoline to the integrated tank of a gas powered generator. But this means there is an extra external propane tank for propane generators that doesn’t exist with gas generators.

For larger generators on wheeled carts, this distinction may be negligible. It will be more of an issue if, for instance, you work on projects that require you to move a portable generator around a lot. In these instances, gas powered generators may be preferable over propane generators.

Propane vs Gas (Are There Other Factors to Consider?)

Yes, there are some miscellaneous factors when it comes to choosing between a propane generator and a gas powered generator. One is the external temperature during usage.

A propane tank uses a regulator to control the pressure inside the tank. In very cold temperatures, this component can freeze up, in which case the tank cannot release the gas.

There is another challenge with operating a propane generator in extreme cold weather. In normal conditions, as the tank converts liquid propane to a gas, it relies on heat from the surrounding air. If the air is too cold, the tank may not dispense the fuel.

Also consider that during a natural disaster there could be a widespread power outage or other conditions that affect the availability of generator fuel. For instance, there may not be an open gas station near you due to lack of electricity to run the gas pumps and other equipment. Or impassable roads may prevent the shipping of both propane and gasoline. Petroleum refining facilities may even be inoperable.

In this case you’re limited to how much fuel you already have. Because propane can be stored indefinitely, it may be easier for you to keep a large supply on hand for this type of extended emergency.

And, if the power outage lasts for a long time, gasoline generators are at a disadvantage because none of them can go more than several hours without a refill. You could find yourself repeatedly going out in foul weather to put more gas in your backup generator, or just to check the fuel gauge.

But propane generators give you the option of running them off of large propane tanks that are capable of providing days of power, depending on your power load.

Is It Cheaper To Run A Generator On Propane Or Gas?

There are instances where gasoline generators can be cheaper to run than propane generators and vice versa. That is because the price of each fuel source can fluctuate. Which one is cheaper at any given time depends on where you live, the vendor, and the current market.

One certain way to compare the cost effectiveness of the two fuel types is with kilowatt-hours (kWh) as the common denominator. If you know the number of pounds of propane and gallons of gasoline it takes to create the same output, then multiply those values with the cost of each and then divide them by kWh. These ratios will tell you which fuel is cheaper, even at different price points.

Dual-Fuel Generators

If you are conflicted about going all-in on choosing between propane vs gas generators, there is a third option available. You can get a dual fuel generator that can run off either propane or gas.

A duel fuel generator tends to be larger than some of the compact, single-fuel generators. However, the option to run both fuels can eliminate some of the disadvantages with generators that run off one fuel or the other.

Personal note: I just bought the dual fuel Duromax XP13000EH to run my entire house.

Learn More About Portable Power Solutions

Now that you have a handle on propane vs gas generator basics, you can make an informed decision about which fuel type is suitable for your business or personal backup power needs. Weigh all the pros and cons with how often and for what purposes you use these power sources, then decide whether a propane or gas generator is the best fit for you.

Did our information on choosing between a propane generator and a gas generator help you? Take a look at our other posts on all things portable power.