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How Long Does a Generator Last? Facts & FAQ

commercial generators

Generally, a standby generator can run around 3,000 hours when powering an average home. However, it is recommended that you don’t run a generator for longer than 500 hours at once, as this can seriously shorten its lifespan.

However, several factors affect how long a whole-house generator can run. For instance, you have to consider the type of fuel you’re using, as well as the generator type. Plus, each generator is designed to run a bit differently.

To determine how long your particular generator might run, we recommend looking at the user manual. Usually, there are instructions on how to extend the lifespan of your generator, as well as how long you can expect it to run continuously. Most generators can run far less time continuously than they can in all.

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How Long Will a Generator Run On 5 Gallons of Gas?

If you only have five gallons of gas, you may have to be a bit picky about when you run your generator. While five gallons of gas is a decent amount, it will only run the average whole-house generator for about 6–7 hours.

For a smaller generator, you may be looking at nearly a week or more of runtime. It all depends on what the generator is powering, the size of the generator, and the quality of the machine. Different generators will run different amounts of time, depending on what the machine was designed to do.

Generators vary a lot. Some of them are only made for powering a small number of electronics, such as those made for camping. Others are made for powering a whole home. Therefore, how long a generator will run on five gallons depends largely on the type of generator.

diesel powered generator
Photo Credit By: anutr tosirikul, Shutterstock

What is the Normal Life of a Generator?

Most generators will need to be repaired at some point. This is a necessary part of maintenance on the generator. Technically, assuming parts are available, you could continuously repair a generator forever. However, there is a point that repairing the generator costs more than the machine is worth. At this point, it is usually suggested to purchase a new machine.

Of course, you also have to consider that technology is advancing. Generators today will be outstepped by new generators at some point. Even if your generator is extremely durable, you may purchase a new one just because of the technological benefits.

If you purchase a generator today, you can expect it to last 15 to 20 years. However, much of this relies on repair parts being available. If they aren’t, the first tiny hiccup could spell the end for your machine. Therefore, checking on the availability of parts is a vital part of purchasing a generator.

Can a Generator Run 24 hours a Day?

For the most part, it depends on the generator. Some generators can run for 24 hours a day. However, others simply aren’t made to do this. Therefore, you should read your machine’s owner manual to determine how long you can safely run it.

Gas-powered generators can run anywhere from a few hours to a whole day. However, most of them cannot run for more than 24 hours at a time. Therefore, it is recommended that you turn them off during certain periods of the day if you’re up against a long-term loss of power. Most people don’t run their generators at night for this reason (and to lower the amount of sound produced).

Some gas-powered generators have large fuel tanks. These are designed to run for days. Therefore, if you want a long-running machine, some options are available.

If you want to run a generator for a few days, though, your best option is a diesel standby generator. These can usually last for a few days before they shut down. Their motors are large and more efficient, allowing them to go through less fuel. Usually, they can also hold a lot of fuel. In the end, this means that they can run for a pretty long time before they need to be re-fueled or shut off.

These generators cannot be run forever, either. It is usually recommended that you only run them for up to 500 hours at a time. Assuming you run the generator continuously, you can use it for 3 weeks.

Of course, if you shut the machine down at night, you can run it much longer.

Usually, at this point, you’re mostly limited by the fuel you have. Therefore, it is recommended that you stock up on fuel to ensure that you can continue to power your generator.

Portable Generator CARB compliant
Photo Credit By: N-sky, Shutterstock

Is It OK to Run a Generator All Night?

It depends on the type of generator. Some backup generators that use diesel are made to be run all the time for weeks on end. These generators are expensive, but they are available for use in your home. Plus, many hospitals and police stations also use them, as they need to ensure that their supply of power never gets interrupted.

However, there are some potential problems with running a generator all night. One of them is carbon monoxide poisoning, which most generators emit. This substance is deadly and nearly impossible to detect. If you have the generator professionally installed, you usually don’t have to worry about this problem. However, for those with portable generators, you often have to consider ventilation.

Furthermore, many generators are not made to be run for more than a few hours at a time. Most portable generators fall into this category. These generators should not be run for an extended period, as they can break as the internal components heat up.

Your user manual should help determine how long your particular machine can run without risking its lifespan.

The gas usage of the machine can also get expensive if it is used all night. Unless you have an extremely efficient machine, you will probably want to turn it off at night to reduce costs. Otherwise, you’ll find yourself needing to refill the tank at night and going through hundreds in gas.

Plus, generators are extremely noisy. During the day, this is less of a problem but at night, it may prevent you and others from sleeping. In some places, you may receive complaints from neighbors (and even a ticket for noise disturbance).

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The time generators are made to run varies widely. Some are only made to run for a few hours and power very few things, such as those advertised for camping. On the other hand, diesel-powered generators are usually made to power a whole home for an extended period. How long your particular generator is made to run at a time can be found in the user manual in most cases.

However, just because a generator can run continuously for days doesn’t mean you should leave it on constantly. In many cases, turning them off at night is recommended. This reduces the fuel you’ll run through, allowing you to use the generator for longer before you run out. It also lowers the noise produced, which can be a serious problem at night.

Often, the main issue with larger generators is running out of fuel. Therefore, having plenty of fuel stocked can prevent you from running dry.

Featured Image Credit: Abhijeet Gaikwad, Unsplash


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