Generators can be used for many different applications such as camping, back up power or work site jobs. While you might only need your generator for a few hours in most cases, prolonged power outages present a unique situation where you might need to run your generator for as long as it can go.
So a common question is how long can you run a generator continuously for.? The answer is more complicated than you might expect, since it depends on the type of generator you have and what type of fuel you’re using. So, we’ll look at several different cases.
Petrol Powered Generators
Portable petrol powered generators will be the most limited in the amount of time you can run your generator. The reason is that you should never refuel your generator while it’s running. Even though it seems tempting to simply pour more fuel into the tank, this is an extremely dangerous thing to do.
A running generator is hot, which presents a risk that fumes from the fuel you’re adding could spark and cause the generator or the fuel tank that you’re holding to burst into flames unexpectedly.
The bottom line: turn off your generator and let it cool down whenever you’re refueling with petrol.
That means that for petrol powered generators, you’re limited to the rated runtime of your generator. Depending on your generator and how much power you are drawing, that may be anywhere from just a few hours to 12 or more hours. But, there are few portable petrol generators with a fuel tank large enough to last for days.
If a long run time is needed on a portable petrol powered generator, we recommend having a model that includes a long range fuel tank
Diesel Standby Generators
If you need to run your generator continuously for more than a few days, a portable generator simply won’t cut it – you need a standby generator.
Standby generators have much larger and more efficient motors that are specifically designed to handle long-term use. They’re also designed to operate on diesel, with the generator model usually having huge long range tanks.
Depending on your standby generator, most manufacturers recommend that you limit your generator to 500 hours of use at the most. That’s about three weeks of continuous use.
While you could potentially run your generator for longer, you will do so at the risk of permanently damaging your standby generator and any appliances plugged into it.
So, if you have a portable petrol generator, you’ll be limited to the runtime of a single fuel tank. This is usually more than a few hours, but far less than a full day.
If you are running a portable generator on a relatively unlimited supply of propane, you’ll be limited to the life of your engine oil. That gives you up to 200 hours, or about eight days, worth of continuous power.
Finally, if you are operating a standby generator with an unlimited fuel supply, you can run your generator for up to 500 hours – 21 days – at a time.
Keep in mind that whenever you are running your generator for extended periods, you need to monitor it. While generators are designed to provide backup power, they can only handle so much abuse and will eventually start to break down. If it’s not strictly necessary to run your generator continuously, it is best to turn it off, let the engine cool down, and perform basic maintenance before turning it on again.