5 Largest Portable Generators On The Market

Discover the largest portable generators on the market so you can fulfill your biggest power needs in a relatively mobile way.

Largest portable generators overview

1. Westinghouse wGen20000 – Largest portable generator (28000 peak watts, <5% THD)
2. Powerhorse 27000 (27000 peak watts, <5% THD)
3. Generac GP17500E (26250 peak watts, high THD)
4. Westinghouse wGen12000DF – Largest portable dual fuel generator (15000 peak watts, <5% THD)
5. AIVOLT 10000 – Largest portable inverter generator (10000 peak watts, dual fuel)
6. Bonus: Westinghouse wGen9500 – Best large portable generator (12500 peak watts, high THD)

I also included a bonus option and the largest portable generators in specific subcategories to give you a good idea of all the options out there.

Other details I looked at

Besides the bonus option, the list above basically contains the portable generators with the biggest starting watts in their subcategory.

That being said, to help you find the right model for your situation, I also looked at other details for the in-depth reviews below.

Some of these details include:

• Run time, fuel efficiency, outlets, noise levels, etc.
• User reviews
• Anecdotal reviews from experts
• Price
• Brand trustability and reputation
• The performance categories below

If a pick seems interesting click it to see the online prices.

*Compared to similar generators and sometimes based on customer input

5 Largest portable generators reviewed in-depth

Having a big amount of power available can be valuable but you likely care about the overall performance of your portable generator too.

The in-depth reviews of all the options can make it easier to find the right model for your preferences and needs.

1. Westinghouse wGen20000 – Largest portable generator

The Westinghouse wGen20000 is the largest portable generator on the market with an impressive 28000 starting watts and 20000 running watts.

That being said, even if you need this much power, it is likely smarter to get two smaller models since you would have to use multiple outlets anyway.

The main reason for this is the above-average rate of technical issues customers have with the Westinghouse wGen20000.

Since you likely don’t want to take the 540 pounds (245 kg) to the store or risk a big investment like this, you likely want to go for smaller portable generators anyway.

At the same time, it is worth noting that the Westinghouse wGen20000 also has positive points.

For example, the electric and remote start make operating the Westinghouse wGen20000 relatively convenient.

Additionally, it may come as a surprise but this large portable generator actually has a low THD rating.

In simpler words, this means the Westinghouse wGen20000 should be able to power sensitive electronics like a microwave, refrigerator, or AC safely.

So the Westinghouse wGen20000 is still an alright portable generator but there are enough reasons to consider other options.

2. Powerhorse 27000

The Powerhorse 27000 is only slightly smaller than the Westinghouse wGen20000 but more promising in terms of reliability.

Additionally, with 27000 starting watts and 18000 running watts, this portable generator should still be big enough for your power needs.

One thing you do want to keep in mind is that there are not that many Powerhorse 27000 customers yet.

Powerhorse tends to be a good generator brand but it is still possible the quality at a bigger scale is suboptimal.

Additionally, the weight of 510 lb (231.33 kg) will take some effort to move around.

The main thing that positively stands out in the Powerhorse 27000 is its relatively low THD of less than 5%.

This makes it so you should be able to run sensitive electronics with this large portable generator.

Besides that, the Powerhorse 27000 is somewhat average in other areas.

This is not necessarily bad considering everything you get for the reasonably sized investment.

3. Generac GP17500E

The Generac GP17500E definitely deserves a spot on the list of largest portable generators with its 26250 starting watts and 17500 running watts.

At the same time, you will likely prefer investing in another model with the rate of technical issues customers have with the Generac GP17500E.

Additionally, the Generac GP17500E produces high THD power.

This means you need your own way to “clean up” the energy if you want to run sensitive electronics safely.

If the Generac GP17500E would be outstanding in other areas, you could potentially risk it.

However, while the run time of 10 hours at 50% load and electric start are nice, these are also not the most exceptional details when it comes to large portable generators.

On top of that, the two years limited residential and one year (or 1000 hours) limited commercial warranties could be better too.

So if you are a big Generac fan, you could theoretically consider the GP17500E.

In practice, you likely want to play it safer at this price point and invest in a more reliable model that is potentially more budget-friendly too.

4. Westinghouse wGen12000DF – Largest portable dual fuel generator

There are a few stronger gasoline-only large portable generators too but it is worth mentioning the Westinghouse wGen12000DF as the biggest dual fuel model available.

The Westinghouse wGen12000DF also does not only offer a lot of power.

There are a few exceptional cases of technical issues but overall, the Westinghouse wGen12000DF is relatively reliable.

You get a nice run time of 11 hours at 50% too.

Although you could consider it, the noise levels of 74 dBA likely make it so you (and your neighbors) don’t want to run the Westinghouse wGen12000DF overnight.

However, the nice run time does allow you to enjoy your power for a long time before having to refuel.

In other areas, the Westinghouse wGen12000DF is very similar to the biggest Westinghouse on this list.

That means convenient operation thanks to the electric and remote start and an optional CO sensor if you want to add a layer of safety.

Something that positively stands out from certain alternatives is the nice warranties of the Westinghouse wGen12000DF.

That being said, with how quality this large dual fuel portable generator is, you should get a lot of power without too many issues.

5. AIVOLT 10000 – Largest portable inverter generator

The AIVOLT 10000 is not the only big option with low THD power but it is the largest portable inverter generator.

In simpler words, the AIVOLT 10000 should be just a bit safer for your sensitive electronics and as you can see, relatively quiet.

With noise levels of 61 dBA (typically measured at 25% load and 23 feet away), this portable generator is barely louder than a standard conversation (typically around 60 decibels).

In combination with the 19 hours run time at 25% load, this makes the AIVOLT 10000 a good option if you want to run bigger AC systems and/or refrigerators overnight.

Because propane typically stores longer than gasoline, the dual fuel feature makes it easier to stay prepared for power outages and live off-grid too.

You do want to know that AIVOLT is not the most proven generator brand out there.

At the time of writing, the reviews are still reasonable overall.

However, it will be interesting to see how the AIVOLT 10000 holds up with more customers.

In short, the AIVOLT 10000 looks like an alright large portable inverter generator with quiet noise levels for now.

If you want to play it safe and don’t mind a bit less power, it could be smart to go for other good large inverter generators.

Bonus: Westinghouse wGen9500 – Best large portable generator

The Westinghouse wGen9500 is somewhat less powerful than many other options on the list but since it is our top pick for the best large portable generator, it does deserve a mention.

Something to note before going into the positives is that the Westinghouse wGen9500 produces high THD power that is not suited for sensitive electronics.

There are also a few very exceptional cases of shipping and technical issues.

That being said, the Westinghouse wGen9500 is still the most reliable big portable generator on this list.

With 12500 starting watts and 9500 running watts, the Westinghouse wGen9500 should provide enough power for many situations too.

Besides that, the Westinghouse wGen9500 is very similar to the other Westinghouse generators on this list.

One exception is that the run time of 8 hours at 50% load is not as impressive.

However, this could still be enough for a comfortable portable generator experience.

Especially if you consider the relatively budget-friendly price of the Westinghouse wGen9500.

Related posts:

• 7 Best Portable Generators For Home Backup
• 5 Quietest Large Generators For A Lot Of Power

FAQ

What is the largest output portable generator available?

The Westinghouse wGen20000 is the largest output portable generator available with 28000 peak watts and 20000 running watts.

If you want the best overall performance and 12500 starting watts is enough for your needs, the Westinghouse wGen9500 is generally the smarter choice.