How Much Gas Does a Generator Use?

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Generators have very much become an integral part of household machinery. In an era like this, having no generator leaves you several years behind everyone. There are many instances of power cut where a generator can come handy. Apart from this, a generator can be useful for outdoor supply of electricity. Camping trips and worksites are also places you can use them. However, you also need to determine how much gas does a generator use! And, this article is aimed at answering this question.

But, a generator is full of specifications and features. You must have little knowledge of it before going out to buy one. The right type of technical knowledge will help you overcome any issues. Few of the main aspects to consider is its running time and especially fuel efficiency.

How Much Gas Does a Generator Use?

To determine how much gas does a generator use, we will look at the different things. It depends on the fuel and type of generator.


Gasoline generators, as mentioned before, are cheaper than their competitors. However, the problems are the storage of gasoline is not that easy and gasoline is expensive too. Still, they are the most used and popular generators. 

A normal 5000 watts’ generator may take up about 18 gallons of gas during a single day. Portable generators are not that pocket friendly. The expensive and unrealistic use of gasoline shows this. But, people have moved towards inverter generators due to their valuable eco mode. That allows you to save gas. When the appliances do not need as much power, the eco mode would save you fuel.

Inverter generators are most efficient in this regard. They have a smaller tank too because they make sure your gas lasts longer. The most effective way to use gasoline generators is to use an inverter one. 

A single tank may have a capacity of 1 to 2 gallons which can last about 8 to 10 hours. This is quite an upgrade from the portable generator. If you are looking for saving more on fuel, you can join two small inverter generators. Connecting them rather than buying a 5000-watt one would save you a lot. They are more efficient and can provide a power of 2000 to 4000 watts.


Diesel generators are a little difficult to find. But, they appear to be more energy-efficient than gasoline ones. This is due to the fact that diesel is less flammable than gasoline. Diesel is also less expensive to buy. 

A 20 kW generator will consume about 1.6 gallons of diesel per hour while running on a 100% load. A 30-kilowatt one will consume 2.9 gallons per hour. The main use of diesel generators is at worksites and in emergencies.

Natural Gas

Natural gas generators are one of the most convenient to use. Natural gas is easy to store. It will easily transfer to your generator too. Either pipeline supply or tanks delivered to your house, you can connect it to your generator. They are good for home use. 

A 20 kilowatt Nat gas generator unit would use about 289ft³/hour at full load. A 30-kilowatt one will use 416ft³/hour at full load.


Propane is one of the eco-friendliest alternatives to gasoline. It is readily available. You can even get one tank at your doorstep. It is cheap, burns safely and has a long shelf life. But, propane is burnt rather quickly. 

A 20-kilowatt generator might take up to 3.44 gallons per hour and a 35-kilowatt one might burn 6.1 gallons per hour.

One of the major drawbacks is the bottle capacity of propane. It takes a single day to consume one propane tank. That is why people often keep 2 to 3 spare tanks in case of emergencies.

If you’d like to store propane at home then you can buy this propane gas cylinder.

The fuel consumption of a generator depends on the wattage it provides. It also depends on the generator type and the engine. Let’s have a look at the types of generators and their fuel consumption.

Types of Generators

With the advancing technology, the generators have evolved too. Currently, different types of generators are floating in the market. These are specific for different uses.

Standby Generator

Standby generators are one of the most powerful generators on the market. For places where all-time power is a necessity, generators are a blessing. Those who want to keep running their appliances during an outage would find these the best. 

Portable Generator

A portable generator is exactly what the name suggests. To increase its mobility there is an addition of several features. An addition of handle and wheels often makes it more maneuverable. This generator is also quite powerful. Yet, its system only allows it to power appliances for a short period of time. You can plug-in appliances like a refrigerator with this. You should make sure you do not connect the central heating or cooling system to it.

Inverter Generator

Inverter generators are the smallest of all. They are more convenient, portable and easy to use. The design of an inverter generator is different. It uses AC supply to convert it into DC. It also has less power compared to others. Charging your phones and other electronics on an inverter generator might be a good idea.

Solar Generators

Solar generators are new in the market. Their fan base is growing gradually. The solar panel absorbs sunlight and sends it to the battery. It converts the sunlight into electricity to charge the battery. This is one of the most eco-friendly methods of generating power supply on small as well as large scale.

Types of Gas a Generator Might Need

It is vital to know what type of fuel your generator requires. This will give you an idea of its fuel efficiency. This will also show its compatibility with other fuels. Some manufacturers decide a single fuel for their generators. Other manufacturers make sure there’s an alternative too.

Most of the generators except for solar generators need fuel to run. How much gas does a generator use will depend on its preferred fuel. They can use one of the following types of gas to provide you with a power supply.

Natural Gas

Natural Gas generators are for people who have an abundant supply of natural gas. Their houses are connected to gas pipelines. Natural gas is better compared to diesel in terms of its effect on the environment. But, it can still cause harm to the environment.

 There is no way of having a storage of Natural gas in your house except for a direct connection to the supply. Delayed start time is a downside to natural gas generators. Natural gas may also cause temporary interruptions in the operation.


Diesel generators are cost-effective and fuel-efficient.; Because, diesel burns slowly, releasing many toxic emissions in the air. These emissions make it hazardous for the environment rating it below EPA standards.


Propane is one of the most multi-purpose fuels. One can use it all around the house as well as for the generator. Propane is readily available and is especially beneficial for people in remote areas. Areas where obtaining fuel is a problem rely on propane generators.


Gasoline Generators are the most used. They are used in homes because they are less expensive and people find it as an advantage. However, they can be costly to maintain and refueling it with gasoline can be a problem. Gasoline is not readily available and in times of emergency, it can be a problem.

How to Refuel Your Generator?

There are a few technical aspects around a generator when it comes to refueling it. Both are critical because you have to make sure you don’t damage the engine in the process. 

Check for Oil and Gas levels

Before refueling your generator, you must keep an eye out for the oil and gas levels. The key for a durable generator and engine is using fresh gasoline. As the gasoline stays in longer inside the tank, the ethanol inside it starts to absorb water. 

Moreover, the tank lies above the engine which can damage the engine too. Apart from that, it might also create problems while starting up the generator. 


 Starting off you need to make sure you run your generator without any cords attached for a few minutes. This will ensure that the generator stabilizes after long use. 

Cool it down

After this, you allow the generator to cool down a bit. This is an extremely important step. If you don’t follow this it may cause an inferno at the spot. The design of the generator makes sure that the gas tank is on the top. This ensures that the engine below it so that the gas can naturally downwards. But, this intelligent design might turn into a disaster if you are not careful. 

If the engine is hot and you are pouring more gasoline in it, it might spark the engine. As a result, this will escalate with a container of gas on the top. Be careful and make sure you let your generator cool down. Cool it down for at least 15 minutes and then start pouring the gas.


Then start pouring in and make sure there aren’t any spillages. 


Even though it is advised to use fresh gasoline, you might not want to do that. Making that many visits to the market especially when it’s a bit far from home can be hectic. In that case, storing some of it in your home is a good idea. However, buying one large can is also not a good idea.

A larger can increases the chances of spilling some of the gas outside due to the sheer size. Moreover, a larger  gas can also risk overflowing the tank. It would suit you better if many multiple small cans preferably 2 cans of 5 gallons.


So, we have listed down all the possible generator choices. We have also listed their fuel consumption. To find how much gas does a generator use, check the fuel and generator type. 

The decision about what generator to buy rests on your use of it. If you have little use but need high power, you would like something less fuel-efficient. But, for everyday use and that too for long hours a fuel-efficient option will be wiser.