Will a 20kW Generator Run My House?

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Will a 20kW Generator Run My House

A 20kw generator can provide enough electricity for a small house. A larger generator may be needed to power an entire home or business.

The size of the generator you need will depend on how much power your household needs and the amount of time used. It’s essential to consider these factors when purchasing a new generator, so you don’t end up with one that is not powerful enough for your needs.

This blog post will discuss how to measure electricity usage and what kind of generator it may require.

Average Home Power Requirements

Depending on the size of the home and the number of appliances in use at any one moment, different homes require varying amounts of electricity. The typical household power consumption, on the other hand, is around 9000KWs per hour.

Because of this, a 20KW generator would be capable of running a home for 2 hours if it were to continue operating normally.

However, when the power goes out, it’s usually a good idea to reduce the number of appliances in use since this will allow the 20KW generator to operate vital household items (such as refrigerators, lighting, and heating) for a more extended amount of time.

Finally, going for a whole house generator of less than 20 KW will result in a more significant fuel expense since you’ll have to refill it more frequently. Not to mention that using a generator puts you at risk of overloading it and causing it to overheat.

When this happens, the likelihood of severely damaging the generator rises significantly, as does the danger of significant damage to your expensive appliances.

How To Calculate The Generator Size You Need For Your Home

To have a good idea of the generator size needed for your home, you’ll need to calculate a few things. The length of time you plan to use it will determine how much wattage your appliances require.

Each appliance has a different electrical draw, measured in watts (W) and amps (A). In general, a standard appliance operates at between 800 and 1200 watts.

Here is a step-by-step guide on how to calculate your generator requirements:

  • Find the wattage values for all of your appliances and add them up. The easiest way to do this is by using a list of appliance wattages (see Resources section below). You can also determine how much electricity each appliance uses by reading its manual.
  • Once you have totaled the wattage values of all of your appliances, you can determine what kind of generator size will be needed. Calculate the starting and running wattage of all devices by multiplying them by 1.5. This ensures that your appliances have enough power even when there are fluctuations in the available electricity.
  • To determine how long a 20KW generator will last, simply divide the generator’s fuel capacity by its fuel consumption rate for a rough estimate.

In conclusion, it’s important to choose a generator based on your household wattage requirements and the length of time you plan to use it. By doing this, you can ensure that your generator is powerful enough for your needs while being less expensive on fuel consumption.

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How Much Power Do Appliances Use? – Appliances and Their Power Requirements

A list of some common appliances that run on electricity and the power requirements for each:

  • Coffee maker – A standard coffee maker uses about (750 to 1200 watts) to heat water and brew a pot of coffee. If you’re brewing three pots in one day, it’s best to leave this appliance off while you’re using the generator.
  • Furnace (600 watts) – The furnace will account for around 10-15% of your total energy consumption, making it one of the biggest power guzzlers in a household. This is why powering a furnace with a 20KW generator can be difficult. However, if you only run the furnace at certain times of day (and keep it off during others), then it’s possible to keep your house warm without much difficulty.
  • Microwave oven – Microwaves are one of the most energy-intensive appliances in a household since they use around 850 to 1800 watts to run, depending on the model. If you want to provide continuous electricity to the microwave, it may be best to unplug it while you use the generator.
  • Refrigerator (500 watts) – A standard refrigerator will need around 500W to work, so powering one with a 20KW generator should be easy if it’s running for no more than an hour at a time. However, if the refrigerator is going to be used for several hours in a row, it may require a generator with more power.
  • Computer (300 watts) – A computer uses around 300W of electricity, which isn’t too much considering that you can turn it off while using the generator.
  • LED TVs (100-120 watts) – Watching TV only accounts for about 1-3% of household electricity usage, making it another appliance that you can use while powering your generator.
  • Water heater (2,200-4500 watts) – If you plan to take a hot shower or run the dishwasher while using the generator, it’s best to skip appliances such as the hot water heater. However, if you’re just going to be using the generator for short periods, then powering a electric hot water heaters will not cause too much of a problem.
  • Portable electric heater (1500 watts) – A standard space heater only uses about 1500W on its highest setting, so it’s pretty energy efficient. If you’re willing to wait a bit longer for your water to heat up, then powering a space heater is possible.
  • Lighting (200 watts) – Lighting accounts for around 5-10% of household energy consumption, so it shouldn’t be too difficult to keep the lights on while using the generator to power other appliances.

There may be more appliances that use electricity in your home; this is just a list of the few more common ones.

How Many Amperes Does a 20kw Generator Provide?

A 20KW generator will typically give you 83 amps of power which is usually enough to power most houses. It will depend on how your home is wired, so it may be best to check with an electrician to make sure that the generator you buy will have enough amperage to run everything you need.

Generator Safety Tips

To ensure that you’re able to use your generator safely and efficiently, there are a few tips that you should keep in mind:

Only Purchase Gasoline With a Rating of 93 Octane or Higher

While it may be tempting to go with the cheaper 87 octane gasoline, this is not recommended as it can cause damage to the internal parts of the generator.

Keep the Generator Dry and Covered

This is especially important when sitting out in cold or wet conditions for an extended period. Moisture and high winds can cause damage to the internal parts, which may lead to your generator not working correctly when you need it most.

Do Not Start or Run the Generator Indoors

Generators can produce carbon monoxide, which is extremely dangerous and potentially fatal. If you plan on using your generator during an emergency, it’s best to do so outside of the house.

Make Sure That Everyone Knows Where the Transfer Switch for the Generator Is Located

This will ensure that nobody turns off or unplugs your generator accidentally, which will cause it to stop working.

Be Careful With Extension Cords

If you decide to use an extension cord for your generator, make sure that the one you purchase is suitably rated. If not, it can potentially damage the generator due to overheating and/or overloading, leading to a fire or other problems.

Use the Right Size Cord

Using a cord that’s too big for your generator can overload it and cause damage, which is why you should purchase the right sized cord for your generator. The same goes with using an extension cord as well.

Important Considerations When Purchasing a Generator

You should keep in mind a few things before you choose which generator to purchase.


When it comes down to it, the generator’s price will be one of the most important considerations when purchasing a generator for your home. This is because you need to make sure that you buy a generator that’s both safe and efficient while still being within your budget.


Since you’ll be purchasing the generator to be used in an emergency, you want to make sure that it’s sturdy and durable enough to handle different weather conditions. If the generator isn’t built to last, it may not be reliable when you need it most, which is why durability is so important.


If your generator is not very efficient, then it’s going to cost you a lot more money in the long run. You don’t want to have to replace the generator after just a few uses because it was inefficient, so it’s best to research different models before making your purchase.


Your generator needs to be equipped with the necessary safety features and precautions so that you and your family can use it without any problems.

Frequently Asked Questions

What size generator do I need to run my AC?

If you have a 5-ton (50-Amp, 60,000 BTUs) air conditioner, you’ll require at least a 20 KW generator.

What size generator do I need to run a refrigerator and freezer?

In order to run a refrigerator and freezer, you’ll need a generator that has an electrical capacity of eight (8) kW.

Will a 2000 watt generator run an air conditioner?

Yes, a 2000 watt generator will run an air conditioner, but you’d need to ensure that the air conditioner’s size matches the generator’s capacity.

How many homes can 100 KW power?

100 KW can power up to five homes.

What size generator do I need for a 200 amp service?

To power a home with 200 amps, you’ll need a generator that has an electrical capacity of at least 15-20 kW.

Final Thoughts

Power generators are an essential home appliance that you should have in your household. While they can be used for several different reasons, their main purpose is to produce power when the electricity goes out, which ensures that you won’t be without power when there’s a major storm or other events that cause the ability to go out for several hours or even days at a time.

Remember that your generator should only be used during an emergency, and it’s essential always to follow all safety precautions when operating a generator to prevent injuries or other problems from occurring.

If you’re unsure about the different types of generators out there, how much power each one has, what capacity they need to be at for you to have enough power, amongst other things, then it’s best to do some research before you make your purchase.

This way, you can ensure that you’re making an educated decision when purchasing a generator, and you know exactly what type of generator will suit your entire household needs!