How Long Can A Backup Generator Run Continuously? 

backup generator

Backup generators are a great piece of equipment to have in your homes. They can power your home in the event of a long power outage, allowing you to run your essential home appliances. People who are planning to invest in a backup generator for their homes have various questions in mind. One of them is “How long can a generator run continuously?” the answer depends on a number of factors, as discussed below.  

Understanding the different types of backup generators 

How long an backup generator can run continuously depends on the type of generator it is and the fuel type it uses. There are different types of generators, each with unique features that make them suitable for specific applications: 

Portable generators 

Portable generators are top-rated for use in homes and small businesses. These are small generators typically fueled by propane or gasoline. These are portable and can be moved around easily. They are a good backup generator options for small power outages, outdoor events, or even camping trips.  

Inverter generators 

This generator works by converting AC electric current into DC electric current and then inverting it back to AC electric current to create a cleaner wave of electricity. They produce stable power that is safe for sensitive appliances such as computers and smartphones. They are quieter and more energy efficient compared to traditional portable generators.  

Standby generators 

Standby generators are large generators that are permanently installed outside a home and connected to the building’s electrical system. These generators turn on automatically when there is a power outage. Standby generators can power the entire home and are suitable for extended power outages.   

Different fuel sources 


It is the most common source of fuel for generators. It has a long shelf life so it can be stored for a long time without worrying about the fuel losing its potency.  

Natural gas 

The generators that run on natural gas are connected directly to the building’s supply line. There is no need for a fuel tank, and the generator can run continuously for as long as the gas lines are functional. However, when a natural disaster strikes, the gas lines are often shut off to prevent fires and other hazards. In this situation, the generator cannot be used.  


Diesel generators are very efficient. However, you are always limited by the amount of diesel you can store in the tank.  

How long will backup generators run during a power outage? 

Theoretically speaking, backup generators can run indefinitely or for as long as the generator is receiving the fuel. Most standby generators run on natural gas, so there is a constant supply of natural gas from the utility company. However, the liquid propane and diesel generators come with a fuel tank, and the run time is limited by the amount of fuel the tank can hold. Most diesel generators have a 24-hour fuel tank, but there are larger tanks available as well. Propane generators typically provide 12-24 hours of continuous power backup.  

Apart from the type and fuel source of the generator, other factors can affect the run time of the generator. These include the engine size of the generator, the age and condition of the generator, the load you are running on the generator, and more. Irrespective of the fuel type used, it is advisable to periodically turn off the generator and allow the engine to cool.  

If you are looking for a standby generator for your home or business, get in touch with us. Our team will help you choose the right generator and ensure that your backup power needs are taken care of.  

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