Buying a generator to help power your appliances and gadgets when the power goes out requires a great deal of research. There’s no one-size-fits-all generator for all your needs, so what works for some people may not work for you.
Of the many things you have to consider when choosing a generator, the fuel type is one of the most important.
You must be curious about propane vs gasoline generator efficiency, and you’re wondering which is more affordable to operate. We get a lot of queries about propane vs gas generators, with most of you asking which one is better.
We hope we can give a one-sentence answer to this question, but we can’t because it’s a lot more complicated than what you think.
Hence, we created this guide on propane generators vs gas generators. We will discuss, in detail, the major differences between these fuel types to help you decide which is more suited for your power backup needs.
What Exactly Is Propane?
Propane is a type of liquefied petroleum gas (LPG). 
It’s a clean-burning and versatile fuel. Nearly every household in the USA use it mostly for producing heat, cooking, and outdoor grilling.
You’ll find portable and standby generators that operate using propane, although it’s more common among standby units.
What Exactly Is Gasoline?
Gasoline is the most common fuel type for backup generators, especially portable models. It’s a transparent, highly flammable fuel made from petroleum liquids, including crude oil.
Typically, gas-powered generators make use of unleaded gas.
Propane vs Gas Generator: The Key Differences
For our comparison, we’ll look closely at how gas and propane generators perform in terms of efficiency, run time, ease of operation, maintenance, availability, cost, pros, cons, and applications.
Propane Vs Gasoline Generator Efficiency
Generator efficiency is the ratio of the electrical power output to the mechanical power input.
Look at it this way: the gas used to power your generator is used to power your home. Thus, if you can maximize the fuel, you can get to operate your household appliances more.
Typically, a 2,200-watt generator will burn through 9.7 cubic meters of natural gas when operating at full load. That means you need around two to three gallons of propane per hour to keep your generator running.
More or less, you need 20 pounds of propane to power your home continuously for five hours.
On average, a generator with a five-gallon gas capacity burns at least 0.75 gallons of fuel per hour. This type of generator can power your home for at least eight hours at half load.
The more power output your generator generates, the faster its fuel burns up. As you can see, a gas generator is generally more efficient than a propane generator because it produces 10% more heat content per gallon of fuel than propane.
Propane vs Gas Generator Run Time
Propane burns faster than gas, so a propane generator has a shorter run time, so you need to store more propane if you’re anticipating a longer power outage.
The good thing about this fuel is that it is easy to store; plus, it doesn’t evaporate easily like gas.
For short power interruptions, you need about a 120-gallon tank of propane, while for extended power outages, you would need at least a 500-gallon tank.
Most underground propane tanks in the USA can hold up to 1,000 gallons of propane. That is good enough to provide your household power source for two weeks. With a monitor, you will know when you are running low on fuel.
A good-quality gas-powered generator has an average run time of 10 to 13 hours at a full tank. The standard 5,000-watt gen-set will use 18 gallons of fuel for 24 hours.
If your unit has an eight-gallon tank capacity, you will need to refill twice, after every 13 hours, approximately, to power your home day and night.
Propane Generator vs Gas Generator Maintenance
While propane and gas generators look very similar, inside those robust shells are engines that work differently. This difference in work mechanisms affects their maintenance needs.
Propane generators often have complicated mechanics. Therefore, encountering a major engine failure during an emergency can be frustrating. In most cases, you need a professional technician to do the job.
If using a propane generator, make sure to have it checked by your trusted mechanic once in a while, especially if you’re anticipating a storm or severe weather.
On the other hand, gas generators feature relatively simpler engines. Since they are more common than propane generators, it’s easier to find replacement parts in case you need one.
In terms of cleaning and maintenance, propane models do better. Propane is a “clean” fuel so it doesn’t produce carbon deposits and other residues in the engine and exhaust. On the contrary, if you’re running a gas generator, you have to clean your engine from time to time.
Propane and Gas Generator Running Costs
Basic portable gas-powered generators for home, outdoor use, and construction sites cost anywhere from $500 to $4,000. Propane generators fall within the same price range, although they tend to be more expensive than similarly powered gas models.
Is It Cheaper To Run a Generator on Propane or Gas?
In terms of fuel price, propane generally costs lower than gasoline. However, considering that it burns more quickly than gas, you will need to purchase more of it to maintain the power supply in your home or job site.
You’ll ultimately spend less on fuel if your generator runs on gasoline than if it runs on propane.
For example, you’ll spend around $4 to $6 per hour on a propane gen-set at $2 per gallon. Meanwhile, you’ll spend approximately $1.87 per hour on gasoline at $2.5 per gallon.
As you can see, the running cost of a propane generator is higher than that of a gas-powered generator. When it comes to equipment maintenance, though, propane generators have a little advantage.
Propane Generator Pros, Cons, and Applications
Propane has its benefits and drawbacks, which you should consider if you’re planning to purchase a generator that runs on it.
Propane is readily available from dedicated providers. Statistics show that more than 10% or about seven million households in the USA use propane for heating. Many rural homeowners who don’t have access to natural gas pipelines rely on propane for heating applications.
If you already have a propane tank on your property, a propane generator might come in handy during power outages. However, if you’re buying propane from refilling stations, expect the cost to be exceedingly high.
Propane providers are also stationed outside city limits which means you have to drive more miles in case you can’t get it delivered to your home.
Propane is considered a clean-burning fuel. Meaning, it produces less amount of pollutants than gas or diesel. Propane generators release just about half of carbon monoxide (CO) emitted by gas-powered generators. 
A major advantage of propane is it’s easy to store. Since it’s liquified, it doesn’t evaporate unless heated.
Compared to gasoline, you can store propane for a longer period. Also, propane tanks have safety valves, so they are less likely to spill.
Even if your propane does leak out of its tank, it poses no environmental hazard. In its unburned state, propane is considered “green” fuel.
Propane Generator Pros, Cons, and Applications
Gas generators are more common than propane generators. But they’re not without some drawbacks.
Gasoline is widely accessible via pump stations. If you’re using a generator for outdoor applications such as camping, you will most likely buy a portable gas-powered model that you can easily refill anywhere.
The only problem is during hurricanes or other weather disasters when gasoline becomes a scarce commodity.
Gas-powered generators have a bad rap in terms of eco-friendliness. When burned, gasoline produces high levels of carbon monoxide, which can be toxic to human and animal health.
They are also prone to fire and electrocution, so you need to handle these generators properly. It’s important to buy a gas generator that has a high level of safety features.
You may be able to stock up on a few gallons for each use. If you need a week or two of fuel, storing gasoline can be expensive and unsafe. Most gas containers don’t have valves. As a volatile gas, this fuel can easily evaporate.
Is a Propane Generator Better Than Gas?
A propane generator might be what you need if:
- You prefer cleaner fuel. Propane is more eco-friendly than gas.
- You want a quiet generator.
- You already have an existing propane tank.
- You anticipate a long-term emergency. Propane can be stored safely for a long time, especially if you have a large tank. If power outages are very common in your area, it might be a good option.
- You prefer a standby generator. The most powerful gas generators may just be enough to keep your household in “survival mode” because they can only power basic appliances.
On the other hand, a propane stationary generator can generate a more stable power output of as much as 15,000 watts that can supply your electricity needs.
When Should You Go With a Gas-Powered Unit?
A gas generator might be what you’re looking for if:
- You want a more efficient fuel source.
- You need a portable generator that you can use for temporary power outages and outdoor purposes like camping.
- You want a more affordable emergency backup solution. Since gasoline generators are simpler machines, they are far less expensive than propane generators.
Which Should You Choose Between the Two?
When choosing between propane and gas-powered generator, always consider your application needs and the fuel available in your area.
Gasoline is easily accessible in everyday situations but can be hard to come by during emergencies. When it comes to propane vs gas generator run time, it also has a good advantage.
Meanwhile, using a propane generator requires planning. You’ll need to install plumbing between your fuel source and generator. You may also need to invest in a permanent tank, but you can store propane indefinitely once everything is set up.
We suggest choosing gas generators if you’re after portability and propane generators if you need a long-term power backup solution for your home.