3 Best 8000-8500 Watt Generators – Reviews & Buying Guide

Power outages are common nowadays. Natural disasters, infrastructural problems, and malfunctions at the grid stations can leave you in the dark for hours, days, and maybe weeks. To navigate such a tough situation, you need alternate power. A generator is a perfect answer to keep you going in such rough circumstances.

If your power needs are high and you want a reliable generator to power most of your home appliances or work machines, then an 8000-8500 watts generator is perfect for you.

Why go for an 8000-8500 watts generator, and what appliances can it run?

An 8000-8500-watt generator can run almost all appliances in your home. With some load management, you can treat it as a whole house generator. You can run an AC, refrigerator, freezer, well pump, water heaters, microwave ovens, heat pumps, TV, lights, fans, and many other appliances. For worksites, an 8000-8500 watt generator can be an ideal option for powering most of your tools. It has enough power to run machines with a big motor and 5-6 medium-sized machines.

Finding the best unit can get pretty challenging when you hunt for the best 8000-8500 watts generator. To help you search for the right machine and make a well-educated and informed decision, we have developed this guide. This guide will review the top three 8000-8500 generators and present you with a buying guide along with a FAQ section. After reading this article, you will be able to select the best unit according to your needs.

Let’s check out the three best 8000-8500 watts generators.

8000-8500 Watt Generators (Comparison)





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Westinghouse WPro8500 Super Duty Industrial Portable Generator

  • Less than 5% THD rating

  • automatic idle control

  • automatic low oil shutdown

DuroMax XP8500E Gas Powered Portable Generator

  • Electric and recoil start

  • Runtime up to 8 hours

  • 16HP fuel-efficient engine

Champion 8.5-KW Home Standby Generator

  • Lower than 5% THD

  • Low-oil shutdown

  • Automatic start

8500-watt Generator Reviews

1. Westinghouse WPro8500 Super Duty Industrial Portable Generator – Overall Best

Westinghouse portable super-duty generator

Fuel Source:This Westinghouse WPro8500 is a portable gas-powered generator.

Start System: You can either turn on the generator manually, electrically, or remotely. There is a simple pull cord mechanism for a recoil start. For an electric start, there is a 3-way ignition switch. And with a remote, you can easily turn on and off your generator from up to 109 yards away.

Engine and Output Power: The 457cc Westinghouse 4-stroke OHV engine can produce 11500 watts of peak power and 8500 watts of rated power.

THD Rating: It is safe to power your sensitive electronics as the generator features less than a 5% THD rating. THD is Total Harmonic Distortion that determines the percentage of distortion present in a signal. The lower the percentage is, the better it will be for smartphones, tablets, and PCs.

Tank Capacity and Runtime: Westinghouse WPro8500 can run up to 17.5 hours on a 6.6-gallon gasoline tank. The automatic idle control feature helps the engine to idle down when no load is applied. This helps in saving fuel and extending the runtime.

Power Outlets: There are two 5V USB ports, one 120V AC 30A outlet, and one 120/240V AC 30A outlet. Also, we have four 120V AC 20A GFCI-protected outlets.

GFCI (Ground Fault Circuit Interrupter) is a circuit breaker that breaks down the circuit when it senses an imbalance between outgoing and incoming current. GFCI protected outlets are for the safety of the users. They protect them from electric shocks.

Certifications and Warranty: It is an EPA (Environmental Protection Agency) and CARB (California Air Resources Board) compliant unit and has a 3-year limited warranty. 

Weight: The weight of this WPro8500 is 192 pounds.

Operational Sound: Its operational sound is not mentioned.

Portability: For easy transportation, there is a lifting hook included, a foam grip fold-down handle, and two never-flat tires. 

Other Features: The other features of this generator include; a fuel gauge, automatic low oil shutdown, and VFT data center.

A fuel gauge helps you to check the fuel levels. The automatic low oil shutdown feature shuts down the engine in no time when it senses the generator is running out of oil. And the VFT data center displays the real-time performance and keeps you up to date with maintenance intervals.

My Opinion:

Pros: Westinghouse WPro8500 is a powerful and reliable generator that gives extremely high surge output. It offers impressive runtime at high power, starts remotely from 108 yards distance, and features GFCI-protected outlets. Also, the unit can be tied into your house through a transfer switch. 

Cons: Its commercial warranty is only for one year.

2. DuroMax XP8500E Gas Powered Portable Generator – Best Lightweight 8500-watt Generator

DuroMax portable generator

Fuel Source:DuroMax XP8500E also runs on gasoline.

Engine and Output Power: It is powered by a 16HP fuel-efficient engine that generates 8500 surge watts and 7000 continuous watts.

Tank Capacity and Runtime: Its 7-gallon gasoline tank capacity is a little higher than the Westinghouse WPro8500. And with this fuel capacity, XP8500e can give a runtime of up to 8 hours at 50% load.

The idle control feature helps you to save fuel to get better runtime.

Start System: Electric and recoil start are the two start mechanisms featured in this generator.

Operational Sound: DuroMax XP8500E operates at 72 dB (A).

Power Outlets: The control panel of DuroMax XP8500E is featured with four 120V 20A GFCI-protected outlets, one 120/240V AC 30A twist-lock outlet, and one 12V DC outlet for battery charging only.

Certifications and Warranty: Its warranty period is 3 years, and it is an EPA and CARB-approved generator.

Weight: XP8500E weighs around 130 pounds that makes it lighter than Westinghouse WPro8500.

Portability: Two durable tires and drop-down handles make transportation easier. 

Other Features: A voltmeter is there, along with a voltage selector switch and a low-oil shutdown sensor. Also, there is a fuel gauge and a built-in spark arrestor.

The voltage selector switch is powered with DuroMax MX2 technology that allows you to switch between full 120V and 120V and 240V simultaneously. And the built-in spark arrestor prevents sparks from coming out of the muffler that allows you to use the generator in parks. 

My Opinion:

Pros: DuroMax XP8500E has a powerful engine that generates impressive output power. It features a big fuel tank that gives a good runtime at half load. It is also lighter in weight and powered by DuroMax MX2 technology. 

Cons: Sometimes, the idle control becomes useless. Also, its customer support service is very poor.

3. Champion 8.5-KW Home Standby Generator – Best 8500-watt Standby Generator

Champion Standby generator for home

Fuel Source: This Champion 100177 home standby generator can run on both natural gas and propane. It is a dual fuel generator.

Start System: A 24V automatic start system allows the generator to turn on when the power goes out. Whether the temperature is -22 F or 104 F, the generator will automatically turn on without a need fora warming kit.

Also, the unit performs self-diagnostic tests every week to make it ready to power every time.

Engine and Output Power: It is featured with a 439cc Champion OHV engine that generates 8500 continuous watts on propane and 7500 continuous watts on natural gas.

THD Rating: Champion 100177 is quite safe for delicate electronics as its THD rating is lower than 5%.

Transfer Switch: There is a sub-panel style 50A transfer switch that comes with eight available circuits.

Fuel Consumption: If you are running your generator on propane, it will consume 1-gallon per hour at the half and 1.5-gallon per hour at full load. But the unit will consume 97.5 cubic feet of natural gas per hour at half load and 139.8 cubic feet per hour at full load.

Related guide: Generator Fuel Consumption Guide

Warranty and Weight: It is obviously a heavyweight unit with 460 pounds of weight and offers a 10-year limited warranty with free lifetime technical support.

Operational Sound: Champion 100177 operates as low as 59.5 dB (A), thanks to its advanced sound dampening system and low-tone muffler.

Other Features: Low-oil shutdown and all-weather composite mounting pad and steel enclosure 

My Opinion:

Pros: Champion 100177 is quite a fantastic home standby generator that produces clean power. It starts automatically in no time, features a 50A 8 circuit transfer switch, and consumes less fuel. Also, it operates quietly.

Cons: The batteries are not included. Also, it cannot run on gasoline.

Buyer’s Guide

Type of generator

One of the most important things to consider while buying an 8000-8500 watts generator is the generator type. Either you can buy a portable generator or go for a standby unit. Each has its pros and cons.

A portable generator is best for people who need a power backup on the go. If you want to use the same unit for powering your home and RVs, then go for a portable generator. It is also best for worksites. You can mount the generator on the back of your truck and power your tools.

Standby generators are best for people who don’t want downtime when the power goes out. It is best for businesses such as banks, restaurants, schools, and colleges. A standby generator starts automatically when grid power is turned off. It is expensive than a portable generator and has more features. It comes with a fully advanced control panel and offers various features like an odometer, fuel gauges, wattage reading, total running hours, and warning lights for low oil and overloading. It needs to be connected through a transfer switch and is wired to your home’s main electrical system.

Type of Fuel

Large portable generators usually run on gasoline, whereas standby units can run on duel fuel. The 8000-watt standby unit on our list can be run on gasoline and natural gas. Gasoline has a higher energy rating than natural gas, but it is difficult to find during a natural disaster and infrastructural problems. During such times, you can power your generator with natural gas. Natural gas is cheaper and has no availability issues. You don’t need to store it; however, its pressure may reduce during winters. Natural gas burns cleaner than gas, but its power output is less than gas.

Peak and Rated Watts

Peak wattage is the maximum power a generator can provide, whereas the rated wattage is the maximum running wattage. Before buying a generator, make sure that all your appliances (individually) have a starting wattage below the generator’s peak wattage. Similarly, calculate the running wattage of your appliances and ensure that it falls under your generator’s maximum running power. If the total starting wattage exceeds your generator’s peak power, you can deal with it by doing load management. Load management means to add motorized machines one by one to the generator and turn off the ones not required at that particular time.

Fuel Tank Size and Runtime

Fuel tank size is also an important feature to consider before buying a generator. Standby generators come with a big fuel tank as compared to portable generators. This doesn’t mean that 8000-watt generators have a small tank. Their fuel tank is also impressive and will provide you with an excellent run time but can’t be compared to a standby unit. Standby generators are large and have space to accommodate larger fuel tanks.

Runtime depends on the size of the fuel tank and the load applied to the unit. If a generator has a large fuel tank, it will give you a higher runtime. When the load applied is above 50% of the generator’s total output, the runtime decreases. To get maximum fuel efficiency and increased runtime, keep the load at or below 50% of the generator’s total output.

Control Panel

Standby generators have a more advanced control panel than portable units. You will get fuel and oil gauges, meter readings for wattage drawn, total running hours, the load applied, on/off button, and warning lights for low oil and overloading. Portable generators also offer such features, but they are not as advanced as standby units. They come with power outlets on the control panel.

Power Outlets

If you are buying a portable 8000-8500-watts generator, look for all the power outlets you may need in the long run. It must have AC/DC outputs for commercial use, along with a conversion output for selecting 120/240V. It helps in powering heavy machines for worksites. For residential use, it must be transfer switch ready.


Portable generators must have all the features that help in moving the unit around. The portable units on our list come with big wheels and carry handles, which facilitate movement. Please keep in mind that if you are going for a heavy generator without wheels, it will be challenging to move it, and you will need 2-3 people for this task. Standby generators are not portable. They are only moved at the time of installation. You will need cranes and lifters to move them from one place to another.

Noise Level

One of the benefits of having a standby unit is a low running sound. They come with high-quality mufflers and silencers, which reduce the operational sound and make the generator quieter. The noise they produce depends on the size of the generator and the power output. For portable generators, make sure their running sound is less than the maximum allowed limit in your area. Anything below 75 DB is fine.

Starting Mechanism

Standby generators have an automatic on/off mechanism. They start automatically within 1-2 seconds of a power outage. For portable generators, you have the option of the electric start or recoil starting models. It would help if you bought a generator with both options, so you have the luxury of not pulling the starting rope every time you need alternate power.


Standby units come equipped with all the latest safety features such as auto shutdown in response to overloading, overheating, low oil, and low fuel. They also have surge voltage protection and keep your sensitive appliances safe from short-circuiting. An advanced portable generator will have all these features as well. However, it would help if you double-checked them before making the purchase. Portable generators must also have covered outlets.

Warranty and Certifications

Another important thing to consider before buying the generator is the warranty. Large generators are costly to maintain; therefore, a warranty is crucial when buying one. It will help save a lot of money on repairs in the first 1-3 years of purchase. It is better to buy a unit approved by EPA and CARB (for California). They help in environmental conservation.


Standby units are costly than portable generators. They are equipped with all the latest features and are more user-friendly. The price of portable generators varies from one model to another and depends on the build quality and the features. We suggest you buy the most advanced unit. What’s the point of saving a few bucks at the time of purchase when you have to spend hundreds on repairs and bear a high running cost?


Which is better; a portable or standby 8000-8500 watts generator?

The answer to this question depends on your needs. If you want to power only your home during blackouts, then go for a standby unit. For RVs, outdoors, and worksites, a portable generator is more appropriate.

Can I use 8000-8500 watts generators for commercial purposes?

Yes. A large-sized generator is perfect for running commercial premises. You can use it to power your offices, construction sites, and off-grid worksites. It can power large and small appliances without any issues.

How long can I run my generator?

It is best to run your generator for a maximum of 6-8 hours continuously. After 8 hours, you must give some rest to your generator. If you have to refuel your generator, make sure it cools down before adding gas to the tank.

What are the maintenance needs and safety protocols of a large generator?

For standby generators, you must take special care while selecting the installation space. It must have a shed overhead to protect the generator from rain and dust. Secondly, you must raise the installation space at least 4-6 inches from the ground and provide ample exhaust and heat exchange space. For portable generators, never run your generator without a generator tent in rain or snow. Always place your generator on flat ground and maintain a distance of at least 15 feet (for standby units as well). The maintenance needs of both the units are almost the same. You need to check the spark plugs, change engine oil and inspect the battery regularly. For standby models, you need to take care of the cooling mechanism as well. Please refer to the user guide for more detail on maintenance and safety standards.

Are there any limitations of the 8000-8500-watt generator?

They are costly to buy and have a high operation cost. Secondly, portable generators are difficult to move around. You will need an additional pair of hands to drag them.


We have explained everything you need to know about 8000-8500 watts generators. The rest is up to you now. Select one from the list above and never stay in the dark. All the generators in our list are high-quality, durable, and will always provide power when needed.

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