May 20, 2022

How Long Can a Generac Generator Run Continuously?

The average US electricity customer experienced over eight hours of power interruptions in 2020. This average includes 14 hurricanes and 11 other major storm events that knocked out the power along the Atlantic coast and elsewhere in the country. New Jersey experienced higher-than-average interruptions, with many electricity customers enduring 16 hours without power.

This may have you wondering—how long can a Generac generator run continuously? Consider the factors that affect home generator run times to help you make the right purchasing decisions.


Provided your Generac generator is in a good state of repair, it should run as long as its fuel supply lasts, just like a car. However, as with any machinery with moving parts, generators require regular maintenance to remain in good condition. The best way to avoid premature wear and tear that could affect run times is to keep the equipment lubricated.

Similar to getting an oil change in your car, Generac recommends replacing the oil every 50 hours of cumulative usage. This means if you need to run your generator for more than two days straight, you should shut it down every 24 to 48 hours to let it cool off and add more oil.


Generators come in two primary types—portable and standby. The type you choose determines how long it can supply your home with electricity during an outage.

Portable generators are generally designed for temporary use, such as concerts or camping, but homeowners and businesses can use them for backup power, too. These generators most often run on gasoline or diesel fuel. 24-hour tanks are the most common size, though 48- and 72-hour tanks are also available. The tank size indicates the maximum length of time the generator can run.

Standby generators are hardwired to your home and automatically kick on when the power goes out. If your Generac standby generator is attached to your home’s natural gas lines, you can supply it with fuel indefinitely!

If natural gas isn’t an option, you can install a liquid propane standby generator. Expect it to burn through about two to three gallons of fuel per hour. With tanks ranging from 250 to 1,000 gallons, you can run your generator anywhere from three to 20 days straight, depending on your usage.


The more electricity you consume during a power outage, the shorter time your Generac generator will run—assuming you have a finite fuel supply. Wattage considerations are also important to ensure you don’t exceed the unit’s maximum power output. For this reason, you may need to avoid using multiple high-wattage appliances at once, including your oven, refrigerator, air conditioner, vacuum cleaner, microwave, and coffee maker.

Seidel Electric Inc is a Certified Select Generac PowerPRO dealer. We supply homeowners and businesses throughout Blairstown, NJ and the entire Tri-State Area with advanced electrical solutions. Trust our qualified technicians to offer their friendly, professional support, whether you need generator installation or repair. To learn more about our generator services and financing options, please contact us at (908) 760-6941.