What Size Generator Do I Need to Run My House: Factors to Consider

Wondering “what size generator do I need to run my house?” Generators are a fantastic way to ensure you have an alternative energy source in case there is a blackout or other power source faults in your residence. There are different questions like “what size standby generator do I need for my house?” that people also think about.

I am going to cover it all in this detailed article on choosing the right size generator. Let us start by mentioning some of the basic factors you should consider while choosing the right size generator and then I will mention some of my top options for generators.

Factors to Consider While Choosing the Right Size Generator

Following are the factors you should consider while choosing a generator:

Power and Wattage

Wattage is the first thing you will need to consider as it represents the total power your generator can support. It also includes the number of appliances including fans, lights, refrigerators, etc it can support. Bigger appliances usually take more wattage. You can refer to the table below to calculate the total wattage support you need before making a purchase.

What Size Generator Do I Need to Run My House? – Comparison Table

The following table represents the performance of generators based on the size of the generator and the load on the generator at 100 percent capacity. There are several factors like elevation, temperature, fuel quality, age, wire size and length, etc which can reduce this performance.

kW Times 1000 divided by (Volts*1.73) *.80

However, this table is just an approximation and can only help make estimations to determine generator performance.

Load  on Generator at 100% Capacity with Performance


The numbers in the above-mentioned table determine the performance in kW of generators with various kVA sizes under their respective voltages. The best way to determine the right size is to add all the lights together. For example, if you have 10 lights, 100 W fits. Refrigerators on the other hand have a high starting current and cycle between on and off. This can be 5 amps adding to 575 watts at 120 volts. However, the starting current can be 6x higher than this.

Similarly, a television draws 80 to 400 watts depending on your TV model. So your standard need will be 1 kW for lights and another kilowatt for television and refrigerator (Approx). However, you need to add another kW for the starting power of the fridge. Therefore, a 6 kVA generator can support these requirements easily.

You should also consider the following other factors for your next generator purchase:

  • Noise produced
  • Fuel Consumption
  • Weight
  • Portability


RELATED: Best Portable Inverter Generators | Best Solar Powered Generators


Types of Generators by Size

Recreational Inverter

  • Offers up to 2,000 watts and costs around $1000
  • Weighs around 60 pounds
  • No installation required
  • Easy transportation

Recommended Product:


Mid Sized Inverter

  • Offers 3500 watts, costs up to $1700
  • Weighs around 150 pounds or lower
  • Runs up to 18 hours with heavier appliances
  • Mostly powers 110-volt appliances only.

Recommended Product:

Westinghouse – WGen9500DF Dual Fuel Portable Generator

Portable Generator

  • Offers up to 7,500 watts, costs up to $2800
  • Weighs around 300 pounds or less
  • Best for occasional power outages
  • Supports an average household easily.

Recommended Product:

DuroMax XP4400E Gas Powered Portable Generator

Large Inverter

  • Offers up to 7,500 watts and costs up to $4000
  • Weighs up to 350 pounds
  • Runs on gasoline instead of natural gas
  • Best for frequent power outages.

Recommended Product:

GoWISE Power PS1004 3000W

Home Standby

  • Offers up to 20,000 watts, costs up to $600
  • Weight up to 600 pounds
  • Automatic power support
  • Nonsuitable for flooding as they are fixed

Recommended Product:

WEN DF475T Dual Fuel Portable Generator

Now that I mentioned these generators in general, have a look at some of the best generator options.

Best Generators for Users

Following are some of the best generator options for users looking for a constant power supply.

Champion 12.5-kW Home Standby Generator

Champion is a relatively new company in the generator industry but tops my list primarily because of its prolonged 10-year warranty. It also has a whisper-quiet 63 DBS of noise that ensures no disturbance in your surroundings while the machine works.

It is a reliable option with operating temperatures ranging between -22° Fahrenheit to 104° on average. The design also has gull-wing access doors, which allows easier maintenance.

Moreover, its weight is 425.5 lb, which isn’t a lot considering the kind of support it provides. I used this generator some time ago and still do. I have to say that I loved it It gave me over 5-6 hours of continuous backup with lighting, fridge, heading, and TV until the local grid power was restored a few years. It also helped my children stay calm in the dark, which would have been a complete disaster otherwise.

Here are a few pros and cons of the generator.

  • 10-year limited warranty
  • Affordable price
  • Extreme temperature start
  • Exhaust pipe points out the side
  • Automatic transfer switch only has 12 ports

Briggs & Stratton 10 kW Automatic Home Standby Generator

Briggs & Stratton 10 kW generator is ideal for residential use because of its compact size and affordable price. Its performance has kept my friend’s house powered up for hours when he had a power outage a few months back. Briggs and Stratton is a company that has provided generators for over a century and has an A+ ranking according to the Better Business Bureau. Here are a few pros and cons he found with his experience with these generators.

  • Convenient installation
  • Quieter than similar units
  • Excellent price point
  • Low power output
  • Unsuitable for large residences

Generac 22000-Watt (LP)/19500-Watt (NG) Air-Cooled

Generac is a good option for me because my uncle needed serious power for a larger home that he lived in. I kept wondering “what size generator do I need to run my refrigerator?” because I needed to recommend him something, and then I found Generac 22000-Watt (LP) generator. It allowed my uncle to power his complete property (which was fairly large). It also offered the MSRP per kilowatt that he could find in the market for an air-cooled generator.

The Generac 2000 offers a consistent power supply, making it ideal for the more delicate appliances inside your home. He stopped thinking “what size portable generator do I need?” and went for a long-term investment with the Generac 2200 and he still admits he is not disappointed. Following are some pros and cons of the generator that you should know about.

  • Lowest cost per kilowatt of
  • 24/7/365 live customer support
  • Easy switch between natural gas and liquid propane
  • Larger footprint means(needs to be placed away from the home)
  • High noise-level

Bottom Line

Choosing the right generator size for your home isn’t difficult if you have the right generator size for your home. It doesn’t matter if you are wondering “what size generator do I need for my RV?” or “what size generator do I need to run my refrigerator?” you can refer to this guide and find the right pick for your needs.

I hope this guide also helps you answer “what size generator do I need to run my house” the next time you go out to make a purchase.

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