How Long Do Generators Last


Home generators can be a lifesaver during a blackout or extended power outage.

They’re also a substantial investment depending on what fuel type and model you choose.

Assessing how long a generator will last is crucial to making an informed purchase decision.

The answer depends on numerous factors.

Read on to find out what they are!

What Factors Affect How Long a Generator Can Last

There’s no definitive answer to how long a generator will last. 

All generators are not created equal.

Individual usage and maintenance habits go a long way toward determining the lifespan of your home generator.

However, numerous factors should be considered when estimating how long a generator should last.

Fuel Type

There are two primary types of home generators. Both output electricity, but that’s where the similarity ends. 

Fossil fuel generators use an internal combustion engine that burns gasoline, diesel, propane, or natural gas and converts kinetic (mechanical) energy into electricity.  

Renewable energy generators rely on intermittent power sources like solar and wind to generate electricity. Both utilize batteries for storage when the sun isn’t shining, or the air is still. 

Wind turbines are primarily used for utility-scale electricity production. The turbines are impractical for most residential applications. 

(Source: Energy Education)

Solar power systems are by far the most prevalent solution for residential applications. Solar panels capture photons from sunlight using the photovoltaic effect. A portable power station or other balance of system stores and converts the DC electricity produced by solar panels into AC electricity for use in your home.

Fuel type is the most significant factor in determining how long a generator will last.      

Brand and Model of Generator

There are so many different models and brands of generators available to choose from.

Even two generators of the same make and model won’t last for exactly the same amount of time.

Some generators are also more expensive than others, but some cheaper generators can easily cost you more in the long run with repairs. And remember, when it comes to gas and propane-powered generators, you have to factor in fuel costs (which isn’t the case for solar generators).

Of course, higher-quality generators will likely be more reliable, too. You’re probably buying a generator so you have reliable access to power when you need it, so make sure that the model you end up purchasing is up for the task. 

Keep in mind that some brands are more reliable than others. 

Check out independent online reviews and choose carefully to ensure you end up with a product you’re happy with. 


Regular maintenance is essential to keep fossil fuel generators running. 

With fossil fuel generators, routine maintenance is essential. Gas, diesel, natural gas, and propane use an internal combustion engine, just like a car or truck.

Depending on the specific model, recommended maintenance can consist of cleaning an air filter or monitoring, changing, and refilling oil and water.

The size of a fossil fuel generator also plays a role here. Depending on where you live and the fuel type, you may be required to get permits and inspections every six months to a year.

If you want a generator without all the fuss, consider a portable power station and solar panels. 

Solar generators are practically maintenance-free and can provide decades of regular use without noticeably diminishing in performance. 

Environmental Conditions

Your location and environment can also significantly impact the lifespan of your generator. 

As a general rule, ensure your generator is installed in a clean, dry place and protected from external elements. 

For fossil fuel generators, this can be a challenge. Depending on the size of the generator, you may be legally required to install it a minimum of 20 feet away from your house. 

Regardless of the size, fossil fuel generators must NEVER be operated indoors. Carbon monoxide poisoning and other emissions can quickly lead to illness or even death. 

Operating a generator in a location that has extreme temperatures — hot or cold — or substantial humidity tends to shorten its lifespan compared to more temperate climates.

Whatever type of generator you opt for, make sure only to use generators safely and according to the manufacturer’s instructions. 

Except for the PV panels, all the components of a solar generator are designed to be installed indoors. 

Unless you purchase a weather-resistant solar power system, shield all components other than the PV panels from the elements per the manufacturer’s instructions and preferably install the balance of the system indoors. 

Installation Quality

Generator installation can significantly impact your generator’s reliability and longevity. Proper installation that ensures adequate ventilation and moisture protection will prolong the lifespan of your generator. 

Professional installation is a must — and likely required by law — for a whole-house standby solar or fossil fuel generator. Unless you’re a licensed electrician, attempting to integrate a backup generator with your home electrical system can be a fatal mistake.

Depending on your location, you may need to have a sturdy cement pad built to protect against seismic activity. 

Of course, not all generators require complex installation. 

Portable power stations, like the EcoFlow DELTA Pro and portable solar panels, for example, don’t require professional installation at all. 


Operating your generator near or at its maximum load capacity for extended periods may put additional stress on it, shortening its lifespan. 

Any generator — fossil fuel or solar — will decline in performance based on how often (how little) — it’s used.

For example, the LiFePO4 batteries in the EcoFlow DELTA Pro Ultra whole home backup solution last up to  3,500 cycles before diminishing to 80% of their original storage capacity.

That’s up to 10 years of daily use. 

Keep in mind that doesn’t mean the EcoFlow DELTA Pro Ultra’s overall performance will diminish by 20%. It simply means the batteries will require more frequent charging. 

If you have enough solar panels installed to recharge the battery during the day, you’ll probably never notice the difference for many more years. However, no currently available battery lasts forever.

But neither does any fossil fuel generator. Even if you never run out of fuel, there are so many moving parts. Eventually, the entire generator — or at least specific components — must be replaced.

How Long Can a Generator Run? 

How long your generator can run depends on numerous factors. 

Once again, fuel type plays the most significant role here.

In the short term, at least, both fossil fuel and solar generators run until their fuel or battery power runs out.

The size of the fuel tank or the battery’s capacity determines the runtime of your generator. 

As a general rule of thumb, units with more storage capacity or bigger fuel tanks run longer without recharging or refueling than units with less storage capacity or a smaller fuel tank when operating the same devices or appliances.

The other primary factor determining runtime is how much electricity you consume. The more appliances you run simultaneously, the more quickly you’ll run out of fuel or stored electricity.

A lesser consideration is how close a generator is to operating at its full load capacity. Typically, when you max out a generator, it will run down faster than if you use it at 75% of its rated load or less.  

Here are some other factors to consider by generator type.

Gasoline Powered

In a gas generator, fuel efficiency can significantly impact runtime — and your wallet. 

Generators with higher fuel efficiency use less gas than those with poor fuel efficiency and the same-sized gas tank. The less fuel consumed to produce the same amount of electricity, the better.

Follow the manufacturer’s instructions to get the best results from your gas generator

That includes performing routine maintenance tasks as directed and operating the generator within suggested limits. 

Diesel Generator 

Diesel is often the go-to choice for commercial backup generators — especially at facilities like hospitals and data centers, where even milliseconds of downtime can be a matter of life and death.

Diesel generators are less commonly used in residential applications. 

As with any fossil fuel generator, fuel storage, supply, and consumption are the most crucial factors to consider when determining how long a diesel generator will run.

Propane Powered

Propane is a cleaner option than diesel or gas, has a longer shelf life, and is easier to store. 

How long your propane generator will run without refueling is determined by the same factors as gas and diesel generators. 

Want the benefits of propane and gasoline? Consider the EcoFlow Smart Generator (Dual Fuel)

Natural Gas Powered

Natural gas generators are connected to the utility grid using a gas line. 

If the electrical grid is down and natural gas infrastructure is unaffected, the generator should run indefinitely or until it suffers a mechanical failure.  

Solar Powered

The runtime of solar generators also depends on supply, storage, and consumption. 

But instead of burning gas, propane, or diesel, solar power relies on how much electricity your photovoltaic modules produce and how much electricity your solar battery can store in excess of your daily consumption.

Renewable energy sources are intermittent by nature. Solar panels don’t work at night. Wind turbines don’t produce electricity when the wind doesn’t blow. 

A solar battery is necessary for a solar generator to operate during a blackout. Grid-tied systems do not operate during outages — unless they also have battery storage. Off-grid solar generators don’t work at all — at least not at night. 

Your runtime with a solar generator is primarily determined by the following factors.

  • Peak sun hours (supply)
  • Solar battery capacity (storage)
  • The starting and running watts of the appliances you wish to operate simultaneously (watts/kilowatts) and for how long (consumption)

You can learn more about how to calculate how many solar panels (watts) and how much battery storage (Wh/kWh) you require to meet your consumption needs here.

The essential factors that determine a generator’s runtime are actually very similar.

What is the biggest difference between fossil fuels and solar?

Fossil fuels are a finite resource that costs money every time you use your generator.

Solar energy is an infinite, clean, renewable fuel source.

Once you’ve achieved solar payback, you can eliminate utility and fuel costs altogether. 

Or at least until your solar generator breaks down or the sun stops shining — whatever comes first.  

Another way of looking at it?

A fossil fuel generator will only ever cost you money over time.

A solar generator can make you money.

A dollar saved is a dollar earned.

How Long Does a Generator Last During a Power Outage? 

Just like how long you can expect your generator to run, how long you can expect a generator to last in the event of a power outage depends on factors like what you’re using it to run, how large your fuel tank or capacity is, and more. 

Because there’s no one-size-fits-all answer to this question, it’s best to determine how long you’d like your generator to run when searching for your generator. 

Consider factors like AC output, what you wish to power, the capacity/fuel tank size, and more when making your ideal selection. 

In terms of the lifespan of your generator, this can also vary hugely based on factors like those we discussed above, including frequency of use, the specific generator you have, maintenance, environmental conditions, and more. 

How To Extend the Lifespan of a Generator

Here are some tips to help extend your generator’s lifespan. 

There might be additional steps you can take for your specific generator, and not all of the steps below will apply, depending on the fuel type and generator model. 

  • Follow Manufacturer Instructions (RTFM): Always adhere to the guidelines provided by the manufacturer.
  • Maintenance: Always perform routine maintenance in a timely fashion as instructed by the manufacturer
  • Protect Your Generator from the Elements: Do not operate your generator in conditions the manufacturer doesn’t recommend. An excellent place to start figuring out what NOT to do is by looking at what voids the generator’s warranty. 
  • Professional Installation: Hire a licensed professional for any generator installation that integrates with your home’s circuit board and wiring. If you DIY, you could be injured or killed. And you’re probably breaking the law. 
  • Storage: Both rechargeable battery and fuel-based generators should come with instructions on how to store them between extended periods without use. Just like parking your car in a garage for three months, when the time comes to use it, it may not work.  
  • Follow Fuel Recommendations: Follow the manufacturer’s instructions regarding the fuel grade and quality you use 
  • Avoid Overloading: Aim to run your generator at 75% of its rated load capacity for gas, diesel, and propane generators. Solar and natural gas generators may be more forgiving.
  • Depth of Discharge: Generators fueled by renewable energy sources (wind, solar) rely on batteries. Depending on the battery chemistry, discharging your battery below 50% can permanently damage your generator. This is particularly true of older battery chemistries — like lead-acid and nickel-cadmium. Lithium-ion and LiFePO4 batteries (like those used in Ecoflow Power Kits) offer a depth of discharge of 80% or higher, effectively increasing your usable storage capacity by a minimum of 60%.

Frequently Asked Questions

What Is the Life Expectancy of a Generator? 

Numerous factors determine the life expectancy of a generator. The most crucial considerations are fuel type, maintenance, electricity consumption, and availability. Fossil fuel generators rely on internal combustion, meaning there are significantly more points of failure. Solar generators have fewer moving parts and require virtually no maintenance.

How Long Do Home Backup Generators Last? 

There is no one-size-fits-all answer to this question. The primary determining factors behind a home backup generator’s lifespan are fuel type, fuel supply, storage capacity, and electricity consumption. Depending on the fuel type, various other factors come into play. As a general rule, solar generators last longer. They’re a better long-term investment because there are no ongoing fuel costs and very few mechanical moving parts — which inevitably fail.

Final Thoughts

There is no definitive answer to how long a home backup generator lasts.

The most essential factors to consider are:

  • Fuel source
  • Fuel supply
  • Electricity consumption

Fossil fuel generators tend to be cheaper upfront.

Solar generators tend to yield a better return on investment over the long term. 

With numerous government incentives fueling the transition to renewable energy sources, there’s never been a better time to switch to solar.

Investing in a solar-powered whole-home generator solution now could save you up to 30% on your purchase and installation costs. 

And that’s with the Residential Clean Energy Credit alone.

Depending on where you live, you may also be eligible for state, local, and utility company incentives.

Not only that, but if you buy directly from the manufacturer, you can finance your purchase over many years.

If making a wise investment in a home backup generator appeals to you, EcoFlow has the answer.

EcoFlow is a portable power and renewable energy solutions company. Since its founding in 2017, EcoFlow has provided peace-of-mind power to customers in over 85 markets through its DELTA and RIVER product lines of portable power stations and eco-friendly accessories.

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