How Long Can a Generator Run? (Exact Run Time)

How Long Can a Generator Run

Knowing how long a generator can run is super important. If you keep it powered on without any consideration, then it may malfunction. In that case, you will have to spend hundreds of bucks on the repair. But if you read this guide, you will save your generator and your hard-earned money. The thing is:

How long a generator can run depends on many things, like generator type, fuel, performance, power output, etc. On average, you can use a standby generator for about 3200 hours and a portable generator for around 15 hours.

Don’t worry; there are different ways to know the exact running time of your generator.

Fortunately, you can even increase it by a couple of hours too.

Keep reading to learn how!

How Long Can a Generator Run?

How Long Can a Generator Run

A high-quality standby generator can run for 3200 hours, but the exact time depends on different factors like fuel. Similarly, a portable generator can power a home for around 15 hours.

Both standby and portable generators can function on different fuels. Note that the running time is different for each.


Running time

Natural Gas generators

As long as you want

(500 hours)

Propane Generators

10 hours

Solar Powered generators

18 hours

Gasoline or Diesel generators

8 hours

How Long Can a Natural Gas Generator Run?

If your generator is on natural gas, then it can run for as long as you want. However, the problem is- when there is a storm, the government cuts the gas supply. Experts say that it is done to ensure no sparking occurs. I support it too!

But in this situation, you can’t use a generator (not even for a minute). You will have to wait for the natural gas supply to get back up before you can turn on the device.

But if there is no natural disaster and a simple power outage, then you can use Natural gas generator without any worry. I recommend you never use a generator for more than 500 hours straight.

How Long Can a Propane Generator Run?

How long a propane generator can operate depends on its fuel efficiency and tank size. But in most cases, I have used it for 10 hours straight. Some models can even run for 18 hours too.

After this, you will have to refill the tank to keep powering your home.

Let me tell you an advantage of Propane– it doesn’t have a shelf life! It means you can store it in your garage for months or even years.

So, you can stock Propane and use it to power your home/RV/Camps in an outage (even if it is caused by a natural disaster).

How Long Can a Solar-Powered Generator Run?

The running time of solar-powered generators depends on the Sun exposure. I have seen people using solar generators for 18 hours straight.

According to my experience, these generators can even power your home for up to 72 hours. For this, install top-quality plates at a sunny spot and use an efficient battery.

But I don’t recommend you start powering every appliance in your home with a solar-powered generator. In my opinion, a few necessary appliances (including a refrigerator) is enough.

How Long Can a Diesel and Gasoline Powered Generator Run?

Diesel and Gasoline-powered generators can usually function for around 8 to 12 hours. A few models can work for 16 hours, but they are expensive.

Here’s a table to sum up the details:

Now, let me tell you the average running time in different scenarios to give you an idea about how long you should use a generator.

Average Run Time of Generators In Different Scenarios

There are three scenarios of using a generator, and all have different average running times.

Short-Term Power Outages

There is an energy outage in your area, you contact the relevant authorities and get the answer that it’s a temporary issue, and the power will be back up in a few hours. In this situation, you can turn on a generator and use all the essential appliances and devices.

As I discussed above, generators can easily function for 10 hours on average. So, there is no need to worry about the running time if the generator’s tank is full.

Extended Power Outages

How Long Can a Generator Run

Let’s say you contact the authorities during an outage, and you get the answer that there is grid failure and the blackout is likely to continue for some days. In this situation, I suggest decreasing running time. Why?

Well, you want to save fuel as much as you can. Plus, you don’t want anything to happen to your generator (especially during an outage).

I recommend you run your generator for a maximum of 5-6 hours and then give it a rest. During this time, you can charge your phones, turn on the refrigerator, and do other essential work.

Remote Locations and Off-Grid Living

How Long Can a Generator Run

If you live in remote locations where there is no grid connection, then you have no choice but to use a generator.

  • If you have a business, then run the device between business hours (9 am to 5 pm).
  • If you reside there, then the average running time will be even higher- possibly around 12 to 16 hours.

Factors That Affect the Run Time of Generators

How Long Can a Generator Run

In my opinion, there are four main factors that impact the running time of generators. Let’s have a look:

  • Fuel Capacity and Efficiency
  • Generator Size
  • Power Output
  • Maintenance and Regular Servicing

Factor #01: Fuel Capacity and Efficiency

Fuel capacity and efficiency is perhaps the biggest impact factor. If your generator has a small tank volume (say it can handle 1 gallon), then its running time will be a few minutes.

Similarly, if a generator has a decent tank volume (let’s say 3 gallons) but the device is not energy efficient, then you won’t be able to use it for long, either.

You should get those generators that have high fuel capacity and efficiency.

The latest generator models of all the credible brands (like Honda, Generac, Champion, etc.) are top-quality.

Factor #02: Generator Size

Generator size is another factor that determines the running time. I prefer to get those generators that are somewhat large (if I want to power up my home or a commercial building).

It is because such generators are manufactured with better equipment and large tanks. So they can operate for a long time.

But for a camping trip, I always take a compact one.

Factor #03: Power Output

Power output also decides how long you can run your generator. If it is high, it means the generator won’t be able to power up your appliances for long.

Factor #04: Maintenance and Regular Servicing

It is crucial I discuss maintenance and regular servicing with you. Every device we use needs some sort of “Upkeeping.” When it comes to generators, you should change the oil, clean filters, get rid of dust, lubricate some parts, etc.

If you don’t, the device’s efficiency will decrease. When this happens, the running time of your generator will start reducing slowly.

Wondering is there any way to estimate the exact running time of your generator? Yes, there is, which I am now discussing.

How Can You Estimate How Long Your Generator Can Run?

There are four ways to estimate the running time of your generator: Checking the manual, looking at the LCD Display, using your own experience, and calculating the load.

Let’s see the details.

Check the Manual First

How Long Can a Generator Run

The running time is usually mentioned in the manual that comes with your generator. If you have lost it, don’t worry. You can go to the official website of the company, search for the generator model you have, and see the details there.

Also, you can go to Amazon, search for your generator model, and read the specifications there.

Look at the Display LCD

How Long Can a Generator Run

The running time is also mentioned on the LCD display of your generator (if it has any). You can also check the remaining fuel and the device’s own estimation of how long you can operate it.

From Your Past Experience

How Long Can a Generator Run

If you use a generator for months, you get the idea of how long you can use it when the tank is full. You become familiar with fuel consumption and know how to handle the device better.

Calculate the Load

How Long Can a Generator Run

I also prefer to calculate the load by dividing the fuel tank capacity with the fuel consumption rate. It lets me know how much more I can use the generator accurately.

But since it is a bit technical, I suggest you go for Manual and Display LCD methods.

Related: What Size Generator Do I Need For a Power Outage?

Tips to Maximize Generator Runtime

How Long Can a Generator Run

There are some proven tips to maximize the generator’s runtime. I have used all of them, so I know they all work.

Determine Your Power Needs

First things first, I recommend you analyze your power needs as soon as you can. This will help you manage lots of things, including the generator run time, your gas bill, etc.

Check which appliances consume the most energy. Make a list.

Then, when you have to run a generator, don’t use such appliances or use them for a few minutes and then turn them off. This will increase the generator’s run time.

Don’t Consistently Run Your Generator

You should not run your generator straight for hours. Here’s what I do. I use it for two hours and then turn it off for 30 to 45 minutes. It helps the device cool down, which prevents any wear and tear.

It also gives me the opportunity to check the fuel levels. We all know that running a generator on low fuel levels can damage the device.

Therefore, follow my advice and don’t consistently run a generator.

Always Get a Generator That Has High Fuel Efficiency

If you have an old generator or from an inferior brand, I recommend you replace it as soon as possible. Such generators only hurt us financially.

Get from top-quality brands like Honda, Yamaha, Generac, etc., as they are fuel efficient. That’s why their average running times are higher than others.

Use Energy-Saving Appliances to Give Your Generator a Relief

You should always purchase energy-saving appliances to lower the burden on the generators. Such products don’t consume much power.

As a result, the running time gets increased.

I recommend you start by getting LED bulbs and then quickly replace all the appliances when you can.

A Transfer Switch is a Good Option Too

I always prefer a Transfer switch because it allows a safe connection between your generator and the electric panel. The chances of back-feeding and sparking get way low due to it.

Hence, the generator doesn’t face any problems during its operation and continues running.

Mix Some Renewable Energy

Another eco-friendly way to increase the performance of generators is to use renewable energy. Get those bulbs, fans, or appliances that can run on solar energy and use them during a power outage.

It will lower the workload on your generator, so it will run for more time.

Inspect the Generator Regularly

You should examine your generator regularly. It will help you spot any problem/error on time. Here’s what I do.

During the inspection, I always check the spark plugs first. They are related to our safety, so it is better to examine them daily.

Then, I see filters and remove dust from them. This ensures proper airflow, which prevents overheating problems.

After this, I check the connections to ensure the operation does not get disrupted.

Your work increases when the weather is bad. During rains or storms, you should use covers to protect your generators (especially standby). If the devices are small, you can bring them. Remember- don’t turn them on in your homes.

Inspection maintains a good condition of a generator, which ultimately increases the running time.

Related: What Size Generator For House?

Final Words

All-inclusive, the running time of generators depends on different factors like device type, fuel consumption, power output, etc. Here’s a summary points to sum up key points:

  • Natural gas generators can generate power for as long as it gets a supply of fuel from the pipes.
  • Propane generators can function for 10 hours.
  • Solar-powered generators can power appliances for 18 hours.
  • Diesel and gasoline-powered generators can run for 8 hours.

But if you follow my suggestions and tips, the running time can increase.

That’s all about how long a generator can run!


Hi, Welcome to; My name is Shahzad, and I know about generators because I grew up in a country where power outage is very common. I share Tips, How-To, News, and Reviews for the best generators or anything related to generators.

Recent Posts