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7 Best Whole House Generators [2020]

Best Whole House Generator

Whole house generators are great sources of backup power for your entire home and all its appliances.

These generators produce power in the upwards of 10,000 watts, with some models exceeding the output of 20,000 watts from their propane or natural gas-powered engines.

Such power is a huge upgrade from that of the smaller portable generators and is ideal for supporting your entire home during outages.

Dive into our top 7 whole house generator reviews and buying guide where we’ll help you chose the model that will meet all your household power needs.

7 Best Whole House Generators – Reviews

IMAGE

​PRODUCT

​FEATURES

Generac 7042

1. Generac 7042 (Smart and Advanced Whole House Generator)

  • Evolution Controller with LCD
  • Self-test quiet-test mode
  • Mobile Link Remote Monitoring
  • High 22,000W/19,500W output
Kohler 20RESCL-200SELS

2. Kohler 20RESCL-200SELS (Fast-response Whole House Generator)

  • High 10-second response time
  • Superior 20,000W output
  • Has an automatic transfer switch
  • Low 5%THD for clean power
Kohler 14RESAL-100LC16

3. Kohler 14RESAL-100LC16 (Whole House Generator with a Multi-circuit Transfer Switch)

  • 16-circuit automatic transfer switch
  • Fast 10-second response time
  • A corrosion-proof enclosure
  • Easy propane-natural gas fuel switching
Champion 100177

4. Champion 100177 (Most Affordable Whole House Generator)

  • Most reasonably priced
  • Automatic transfer switch included
  • Low 59.5 dBA noise level
  • Performs weekly self-diagnosis
Champion 100294

5. Champion 100294 (All-season Whole House Generator)

  • Seamless starting in extreme weather
  • Performs weekly self-diagnosis
  • Has an automatic transfer switch
  • Reduced 63 dBA noise output
Briggs & Stratton 40450

6. Briggs & Stratton 40450 (Best Compact Whole House Generator)

  • Compact size for tight installation
  • Installable 18 inches from the house
  • Automatic transfer switch included
  • Front air ventilation system
Briggs & Stratton 076180

7. Briggs & Stratton 076180 (High-performance Whole House Generator)

  • Superior 25,000W output
  • Symphony II Power Management
  • Air-cooled dependable engine
  • Durable galvannealed steel build

PRODUCT

1. Generac 7042

(Smart and Advanced Whole House Generator)

Generac 7042
  • Evolution Controller with LCD
  • Self-test quiet-test mode
  • Mobile Link Remote Monitoring
  • High 22,000W/19,500W output

2. Kohler 20RESCL-200SELS

(Fast-response Whole House Generator)

Kohler 20RESCL-200SELS
  • High 10-second response time
  • Superior 20,000W output
  • Has an automatic transfer switch
  • Low 5%THD for clean power

3. Kohler 14RESAL-100LC16

(Whole House Generator with a Multi-circuit Transfer Switch)

Kohler 14RESAL-100LC16
  • 16-circuit automatic transfer switch
  • Fast 10-second response time
  • A corrosion-proof enclosure
  • Easy propane-natural gas fuel switching

4. Champion 100177

(Most Affordable Whole House Generator)

Champion 100177
  • Most reasonably priced
  • Automatic transfer switch included
  • Low 59.5 dBA noise level
  • Performs weekly self-diagnosis

5. Champion 100294

(All-season Whole House Generator)

Champion 100294
  • Seamless starting in extreme weather
  • Performs weekly self-diagnosis
  • Has an automatic transfer switch
  • Reduced 63 dBA noise output

6. Briggs & Stratton 40450

(Best Compact Whole House Generator)

Briggs & Stratton 40450
  • Compact size for tight installation
  • Installable 18 inches from the house
  • Automatic transfer switch included
  • Front air ventilation system

7. Briggs & Stratton 076180

(High-performance Whole House Generator)

Briggs & Stratton 076180
  • Superior 25,000W output
  • Symphony II Power Management
  • Air-cooled dependable engine
  • Durable galvannealed steel build

1. Generac 7042 – Smart and Advanced Whole House Generator

Generac 7042
  • Power Source: Liquid Propane/Natural Gas
  • Rated Watts: 22,000 Watts/19,500 Watts
  • Rated Volts: 120 Volts/240 Volts
  • Engine: 999cc V-Twin

Generac 7042 is one of the smartest, technologically-advanced, and powerful whole house generators you can buy today.

We start with its Generac Evolution Controller, which includes a multilingual LCD display that helps in battery status monitoring and maintenance tracking.

Then comes its quiet-test self-test mode, which enables the generator to run at lower RPMs for a period of 5-12 minutes ensuring the unit consumes less fuel while running significantly quieter.

You’ll also love the mobile link remote monitoring feature, which allows you to track your generator’s performance from anywhere in the world using your phone, PC or tablet.

All these features are on top of the immense power the generator produces from its 999cc engine. Propane fuel will produce 22,000 watts of power while natural gas will yield 19,500 watts. You can power all your intensive household appliances simultaneously with this generator.

An issue we found limiting is the fact that the Generac 5819 26R battery required for starting this air-cooled is not included and has to be bought separately.

Pros:

  • Multilingual LCD controller
  • Self-test mode for generator efficiency
  • Remote generator monitoring
  • Superior power output

Cons:

  • The required battery is not included

2. Kohler 20RESCL-200SELS – Fast-response Whole House Generator

Kohler 20RESCL-200SELS
  • Power Source: Liquid Propane/Natural Gas
  • Rated Watts: 20,000 Watts/18,000Watts
  • Rated Volts: 120 Volts/240 Volts
  • Engine: 999cc V-Twin

Kohler 20RESCL-200SELS is a fast-response whole house generator that will kick in about 10 seconds after a power blackout.

It is ideal for homes with sensitive appliances that cannot go for long without being powered. This 20,000-watt generator will automatically start as soon as the power goes off.

This backup generator also comes with a 200Amp whole-house automatic transfer switch, which has load-shedding capabilities and is service-entrance rated. It is this tool’s efficient switching capability that enables the generator to respond in record time when power fails.

Another impressive feature you’ll love is the 100% corrosion-proof enclosure, which provides the generator with protection from even the harshest seaside conditions, which are notorious with causing components to corrode.

You also get premium power quality from this generator from its 999cc V-Twin engine, which has a +/-1% voltage regulation, and a less than 5% total harmonic distortion (THD), which protects you vulnerable and sensitive electronics by feeding them with clean and stable power.

Kohler 20RESCL-200SELS is, however, one of the priciest whole house generators we have reviewed. Budget buyers may find this model hard to access.

Pros:

  • High response time
  • Superior power output
  • Comes with an automatic transfer switch
  • Low THD for clean, stable power

Cons:

  • Pricey

3. Kohler 14RESAL-100LC16 – Whole House Generator with a Multi-circuit Transfer Switch

Kohler 14RESAL-100LC16
  • Power Source: Liquid Propane/Natural Gas
  • Rated Watts: 14,000 Watts/12,000 Watts
  • Rated Volts: 120 Volts/240 Volts
  • Engine: 725cc V-Twin

Kohler 14RESAL-100LC16 is a whole generator whose included automatic transfer switch offers multiple circuits for versatility and maximum appliance support.

This generator comes with an RXT 100Amp indoor-rated automatic transfer switch, which bears a 16-circuit center for maximum appliance support during power outages. This switch is also carb-compliant.

During power outages, this generator automatically starts in 10 seconds and restore power automatically to your heavy-duty appliances, including a 5-ton (60,000 BTU) air conditioner, and many others.

You don’t have to worry about installing this generator in your seaside home as it comes with a 100% corrosion-proof enclosure that will protect from the harsh seawater.

It runs on either liquid propane or natural gas, and switching between these two fuel sources has been simplified so that you don’t have to do any work in this process.

A disappointing discovery we made in the Kohler 14RESAL-100LC16 is that it requires a battery, Group 51, 6VSG, 8/10/12RESV(L), which is sold separately by Kohler.

Pros:

  • Multi-circuit automatic transfer switch
  • Fast response time
  • Has a corrosion-proof build
  • Easy fuel switching

Cons:

  • The required battery is not included

4. Champion 100177 – Most Affordable Whole House Generator

Champion 100177
  • Power Source: Liquid Propane/Natural Gas
  • Rated Watts: 8,500 Watts/7,500 Watts
  • Rated Volts: 120 Volts/240 Volts
  • Engine: 439cc 4-Stroke V-Twin

Champion 100177 is the most affordable whole house generator on our list and is ideal for homeowners on a budget, who need reliable backup power for their households.

We consider this generator a budget option because its price is 3 times lower than that of the most expensive model, the Briggs & Stratton 076180.

This generator will kick in automatically during a power outage, a capability made possible by the 50Amp Champion ATS50 Emergency Essential transfer switch that is included with the generator.

It also features a sound-dampening lining and low-tone muffler, which combine for superior noise reduction through a baffle system that makes this unique one of the quietest in its class. The generator produces only 59.5 dBA of noise.

For ease of maintenance, the unit produces weekly self-diagnostic tests on its 439cc OHV engine and power system. If you opt to use propane, the generator will give you 8,500 watts while natural gas will produce 7,500 watts of power, enough for light-to-medium home appliances.

The power of this affordable Champion 100177 is, however, in the lower range compared to that of rival models.

Pros:

  • Reasonably priced
  • An automatic transfer switch is included
  • Low noise level
  • Easy self-maintenance

Cons:

  • Lower power compared to rival models

5. Champion 100294 – All-season Whole House Generator

Champion 100294
  • Power Source: Liquid Propane/Natural Gas
  • Rated Watts: 14,000 Watts/12,500 Watts
  • Rated Volts: 120 Volts/240 Volts
  • Engine: 754cc 4-Stroke V-Twin

Champion 100294 is a whole house generator built to thrive through all seasons of the year because of its high build quality and protective features.

This backup generator comes with a 24-volt starting system capable of operating efficiently in extreme or sub-zero heat, between -22 degrees Fahrenheit and 104 degrees Fahrenheit. No warming kit is necessary for this generator.

To ensure it is running smoothly and optimally at all times, Champion 100294 performs weekly self-diagnosis tests so minimal motoring and maintenance are required from you.

It also comes with an ATS200 automatic transfer switch with 8 available circuits included. This unit is also service-entry rated. Combined with an onboard battery, the whole unit triggers seamlessly during power outages.

A sound-dampening lining and a low-tone muffler have been included to reduce noise output, making this one of the quietest generators in its class.

Setting up the Champion 100294 may, however, require some costly plumbing to connect the unit to a propane fuel supply.

Pros:

  • Starts flawlessly in extreme weather
  • Performs regular self-diagnosis
  • An automatic transfer switch included
  • Reduced noise output

Cons:

  • Setup may incur additional costs

6. Briggs & Stratton 40450 – Best Compact Whole House Generator

Briggs & Stratton 40450
  • Power Source: Liquid Propane/Natural Gas
  • Rated Watts: 10,000 Watts/9,000 Watts
  • Rated Volts: 120 Volts/240 Volts
  • Engine: 570cc V-Twin

If you have limited available installation space for your backup generator, then you’ll love the Briggs & Stratton 40450, which is the most compact whole house generator on our list.

The unit measures only 28 x 24.4 x 35.1 inches in size. In case you have tight lot lines, you can install it just 18 inches from your house as it adheres to the National Fire Protection Agency 37 standard. The generator is ideal for households of up to 4,200 square feet in size.

Also included with this generator is a 200Amp Symphony II automatic transfer switch, which enables seamless switching of emergency backup when a power blackout occurs. This combination of a generator and transfer switch gives you great value for money.

Its front air ventilation feature directs engine exhaust fumes out the unit’s front and away from your home.

A disappointing discovery we made about the Briggs & Stratton 40450 is that its required battery, 540 CCA, is not included and has to be bought separately.

Pros:

  • Compact for little space occupation
  • Can be installed close to the house
  • Comes with an automatic transfer switch
  • Efficient ventilation system

Cons:

  • The required battery is not included

7. Briggs & Stratton 076180 – High-performance Whole House Generator

Briggs & Stratton 076180
  • Power Source: Natural Gas/Liquid Propane
  • Rated Watts: 25,000 Watts
  • Rated Volts: 120 Volts/240 Volts
  • Engine: 1600cc

Briggs & Stratton 076180 takes the crown of the leading high-performance whole house generator with its powerful engine and superior power output.

This standby generator produces 25,000 watts of power, which is the highest output of all the models we have reviewed on our list. This power is enough to support both high and low-demand appliances in your home.

All this power is managed by the Symphony II Power Management system and a 200Amp transfer switch, which orchestrates power between high-demand appliances such as air conditioners and ovens, and lighter ones, efficiently.

It boasts of a 1600cc air-cooled engine that is efficient and dependable. The engine offers you easy conversion options between natural gas and liquid propane fuel during installation.

To ensure your generator provides long-lasting reliability, its base and enclosure are made using galvannealed steel that is rust-resistant. A powder-coated paint layer is added to provide abrasion-resistance.

A key downside of the high-performance Briggs & Stratton 076180 is that the recommended Briggs & Stratton 200Amp Symphony I​I automatic transfer switch has to be bought separately.

The generator is also the cost expensive on our list and is not accessible to budget buyers.

Pros:

  • Superior power output
  • Smart management of power demands
  • Efficient engine cooling and fuel switching
  • Strong and durable build

Cons:

  • Recommended automatic transfer switch sold separately
  • Very expensive

Standby (Whole House) vs. Portable Generator

Standby (Whole House) vs. Portable Generator

Although both portable and standby (whole house) generators serve the same basic purpose of providing you with backup or emergency power, they differ significantly in features, cost, and performance.

Below, we highlight the main differences in features between the two types of generators and help you decide which one is best for your home.


Portable Generator

Backup Generator

1. Fuel Source

Powered by either natural gas or liquid propane

Mostly run on gasoline, but some are battery-powered

2. Price

Mostly affordable

Significantly pricey

3. Power Output

Ranges from 150 watts (low) to 4000 watts (high)

Produces 5,000 watts to 25,000 watts of power (or more)

4. Weight

Most weigh below 100 pounds

Most weigh over 200 pounds and get heavier with bigger engine sizes

5. Noise Levels

Low noise levels in the range of 50 dBA to 60 dBA

Most have higher noise levels of over 60 dBA

6. Installation

  • Portable and can be used in multiple settings
  • Don’t require professional installation
  • Installed in fixed locations
  • Require professional installation

7. Weatherproofing

Not pre-installed and may require additional accessories

Most have weather-proof housing

8. Run time

Varies depending on the fuel tank and engine size

Varies depending on engine size and fuel type

9. Load support

Small-to-medium appliances

Simultaneous power-intensive appliance support

From the comparison above, the differences between the two types of generators become clearer.

If you’re looking for a generator that will support almost all of your home’s power demands, you can opt for a standby generator, which produces more power and has simultaneous multi-appliance support. However, standby generators are significantly pricier than portable ones.

Portable generators are, on the other hand, more affordable, less noisy and lighter than standby ones. You also don’t need a professional or fixed installation of portable generators.

However, they are not as powerful and versatile in supporting multiple appliances as standby ones are. 

How to Buy the Best Whole House Generator

How to Buy the Best Whole House Generator

1. Your Power Demand

Your home power demands will determine, to a great extent, the generator model you’ll buy.

If you run high-consumption appliances such as air conditioners, microwaves, and advanced lighting systems, a powerful generator exceeding a wattage of 15,000 watts is the ideal choice.

On the other hand, if you just need a backup generator to power your essential tool long enough for the power to resume, then 5000-watt to 10,000-watt one will serve such needs.

It’s worth noting that whole-house backup generators get pricier as their power output increases. The most powerful generator on our list, Briggs & Stratton 076180, almost hits the 10,000-dollar mark.

2. Power Source

For whole house generators, there are two main options for power sources: liquid propane (LPG) or natural gas.

Something you’ll notice from our reviews is that propane-powered generators produce more power (in watts) than a natural gas-powered one. This occurrence is attributed to the fact that propane has a higher BTU (British Thermal Unit) than natural gas.

A higher BTU means more fuel-burning efficiency and cleaner energy. In the case of the 2 fuel sources, propane has a higher BTU than natural gas.

You may prefer natural gas because it is readily available through a pipeline to your house.

3. Rated Watts/Rated Volts

Rated watts are the power outputs of your whole house generator while rated volts are the equivalent voltage outputs.

The outputs of your unit will depend on its engine strength and other factors that combine to make the generator whole, such as the fuel source.

In the case of propane-powered generators, the power output (watts) higher than the same in natural gas-powered units.

Powerful engines, such as those exceeding 900cc can produce rated power in excess of 15,000 watts, while smaller ones can manage outputs of 5,000 watts to 12,000 watts.

Almost all whole house generators will support both 120-volt and 240-volt outputs for maximum appliance compatibility.

4. Engine

As noted above, whole-house backup generators are powered by natural gas or liquid propane engines.

Your engine strength is measured using displacement, in cubic centimeters (cc).

High-performance engines have a displacement of 900cc and above. Such engines will produce power between 18,000 watts and 25,000 watts depending on the fuel sources.

Mid-range engines of 700cc-900cc have outputs of between 10,000 watts and 14,000 watts while the low-performance ones of 400cc-500cc can manage 5,000 watts to 10,000 watts in power output.

It’s worth noting that powerful engines make the whole generator unit both heavy and expensive.

5. Fuel Consumption

It’s important to consider how much fuel your generator unit will consume so that you are fully aware of its operating costs.

For propane-powered generators, fuel consumption is calculated in gallons per hour (gal/h) because the fuel is usually compressed into a liquid. Natural gas consumption is measured in cubic feet per hour (ft³/h). Both fuel consumption rates can be calculated at half or full load.

Although fuel consumption rate of natural gas or propane will most certainly model-specific, perhaps the most important thing to note is that the higher the power output of your generator, the more the fuel it consumes.

6. Noise Level

Whole-house backup generators produce a considerable amount of noise, especially compared to portable ones, which are less noisy.

The reason for the noise is because larger backup generators have powerful engines that run on either propane or natural gas.

Luckily for you, a lot of technology goes into making backup generators quiet. Some of the high-performing models we’ve reviewed have noise levels in the 60-dBA range, which is near the portable generator territory.

Conclusion

Having explored the leading whole house generator models and their range of features, you’re well-equipped to proceed and get one for your home.

Remember to check the rated power and voltage output, fuel source and consumption rates, which will help determine if the generator can meet your energy requirements.

From our reviews, we recommend the Generac 7042 backup generator because of its advanced features, high output power, and mid-range pricing combination.

You can always count on our top 7 whole house generator review and buying guide to help you choose the model that suits your home’s power needs best.