How many Watt Generator Do I Need To Run Home Appliances

Have you had enough of being hampered while doing your important work during power cuts? A complete house generator is a solution for you. Do you know how many watt generator do you need for your entire house?  However, not everyone’s house is the same size. Though there are variations in sizes of houses, the average size is 1200-1500sqf. 

If you need to run multiple essential appliances for an average house, get a 10,000-watt generator. You can run small appliances, water pump, air-conditioner, refrigerator, and lights with this size generator. 

You will see generators available in the market of different features and sizes. While buying a generator, our common misconception is to choose it by its physical size. 

But, in actuality, generators are categorized based on their electrical output.  Watts or kilowatts are the basic measurements of generators (1KW = 1,000W).  

There is no time for sitting idle in the darkness with zero charged electrical gadgets. And, if it is summer, we can’t think without the air conditioner. And, what about your refrigerator that you just filled with fresh food yesterday; without electricity supply, I have a doubt how long they’ll remain fresh. 

So, what is the solution? It’s high time you bring home a backup system that prevents your lifestyle from collapsing. Yes, you got me right; an alternative power source is all you need in such circumstances. 

But do you know how many watt generator do you need? 

Size matters. You can’t pick any random size generator for your home. Why? Let me explain. Too small or extra-large, both types have their drawbacks. 

Why to Choose the Right Size & Watt Generator?

What do you understand about the right size of generator?

The terms of size refer to the wattage as well as the physical dimension of a generator. The measurements of the electrical power of the machine are kilowatts or watts. You have to be very careful at comparing the electricity power of several generators based on how much power any home appliance requires. 

What happens if you use a smaller inverter compared to your appliance? When a generator provides less power than the requirement, the device may face a voltage drop. Additionally, it becomes hard for that particular generator to maintain the required voltage. As a result, it gets slows down, strangling the electricity to the appliance. 

Asking to provide more electric power than its capacity leads a generator to perform poorly and can cause damage to your home appliances. Due to overworking, it may get overheated. A malfunctioned generator can result in bursting that shortens the lifespan of any connected device. 

How would you know that the generator is overworking? Not only is the connected appliance, a generator that doesn’t match the minimum watt requirement also harmful to itself. While trying so hard to provide more power than its range, the low-watt generator may get overloaded, emitting excessive heat.

 If you notice a flaky or deep black powdery substance along with amorphous carbon in the generator’s exhaust, it is clear evidence of overworking.  This sign confirms that a clog is occurring inside, resulting in the machine struggling for the filter. 

How dangerous could this situation get? This kind of over-heating stage may result in an explosion. If you find a gas tank close to the unit of your generator, be careful as a spark can provoke the fire. 

Are the exploded generator parts replaceable? Immoderate overuse significantly decreases the longevity of a generator. And, if the expensive parts of a generator like a stator, alternator get burned, replacing is better than buying a new one. 

What if you buy an extra high-watt generator? Overly big wattage generators can come in high-price based on the brand, installer, and fuel type. For example, a 16kW generator price will be higher than an 11kW one. So, if your purpose fulfills with an 11kW alternator, then why do you need to go for an extra wattage product. 

Have you counted on the operating costs of a generator that would increase with the capacity? For example, if yours is a liquid propane alternator, then the requirement of fuel will be more to fill the big tank. Additionally, you have to pay extra money for the maintenance cost of a bigger unit. 

So, why not act smartly? Go for the appropriate size of generator for your home. 

Now the common question is- how big of a generator do I need for my house?  Let’s find the answer together. 

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What are the Types of Generators?

Do you know that some of your home appliances can draw more wattage than your approximation while operating? Yes, it is true. 

Though you can get an approximation of the required wattage for running your home appliances during a power cut, you should also include the extra wattage in your calculation. 

Here you will get to know different types of generators and what will they run in your home- 

Recreational Inverter (up to 2,000 watts)

This generator can run- laptop (200W), Fridge (700W), 5-10 lights (250W), home security system (100W), and Smartphone charger (20W). 

Champion Power Equipment 100692 2000-Watt Portable Inverter Generator, Ultralight

Champion Power Equipment 100692 2000-Watt 

  • Wattage: 2000 watts
  • Weight: 39.5 Pounds
  • Fuel Type: Gasoline

Mid Sized Inverter (up to 3,500 watts)

This type of generator gets you- laptop (200W), fridge (700W), 5-10 lights (250W), home security system (100W), and Smartphone charger (20W). Additionally, you can get a 1,000W air conditioner or one of these appliances- hairdryer (1,200W), toaster oven (1,200W), space heater (1,500 W), washing machine (1,200 W), and coffee maker (1,000 W).

Westinghouse Outdoor Power Equipment WGen3600v

  • Wattage: 3600 watts
  • Weight: 99 Pounds
  • Fuel Type: Gasoline

Portable or Large Inverter (up to 7,500 watts)

You can get a laptop (200W), Fridge (700W), 5-10 lights (250 W), home security system (100W), Smartphone charger (20W), and 10K BTU AC (1,000W) to run. Additionally, you can get- sump pump (900W), a Well pump (1,250W), and propane or gas furnace (800W), or one of these items- an electric range (2,000W), dishwasher (1,500 W), or 8-inch burner. 

DuroMax XP13000E Gas Powered Portable Generator

  • Wattage: 10500 watts
  • Weight: 227 Pounds
  • Fuel Type: Gasoline

Home standby (up to 20,000 watts)

This size generator will get you to run all the appliances in the home.

Generac 70422 Home Standby Generator Guardian Series 22/19.5kW Air-Cooled with Wi-Fi, Aluminum

  • Wattage: 19500 watts
  • Weight: 525 Pounds
  • Fuel Type: Natural Gas/LP

What size generator do I need for my house?

You run multiple devices in your home like refrigerator, AC, TV, desktop, laptop, mobile, microwave oven, washing machine, and more. You need to choose a generator that provides power support to all these home appliances. When you’re deciding what size generator do I need for a 3- bedroom house, you must keep in consider these 3-things below- 

  • Number of people
  • How often do you need to run the generator, and 
  • What you want to get powered during power-cut

Many family members use different home appliances as well as electricity. If there is no use of any large wattage appliance such as an air-conditioner, dryer, microwave oven, etc., then a 3,000 watts generator will do well for a typical house consisting of 3 bedrooms. But if you run essential appliances at a time, you would need the more powerful generator, about 6,000 watts. 

What size generator to run a refrigerator and freezer?

We all have different models of refrigerators at home requiring different wattage. If you have any queries about- what size generator do I need to run a freezer; you can check the manufacturer’s guide

AKA surge wattage or starting wattage and running wattage- you should keep these two things you have to keep in consideration while buying a generator.  Starting wattage means the energy your freezer needs to get started. And, running wattage refers to the power that the refrigerator requires after startup to run continuously.

Based on the size, refrigerators require around 1000-2000 AKA surge wattage on average. That means, if you choose a generator providing at least 2000 wattage at the initial starting, there will be no issue running your freezer or refrigerator.

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How to calculate what size generator do I Need For My house

Do you know how many amps your home appliances use on average? Yes, it is another essential step that will help you to figure out the generator size. You can gather this information from the manufacturer of a particular appliance. 

For example- an air conditioner uses 10-15 Amps, a Dishwasher takes 3-4 Amps, and a refrigerator uses 1 Amp. 

While calculating how many watt generators you need, you have to consider two main points-

  1. Running wattage or continuous power that your appliances need to operate under regular load.
  2. Startup watts or extra peak power is what appliances require at the highest level of power consumption or startup.

Though we generally don’t run all the home appliances at a time, here is a chart for your convenience- 

Home AppliancesStarting WattageRunning Wattage
Washing Machine1,2001,200
Clothes dryer6,5705,400
Refrigerator 2,900 700
2-ton Central AC8,7503,800
Electric Water Heater4,5004,500
Security System550550
2 TV’s (46”)380380
Refrigerator- (Dorm Size)350500
Microwave Oven (800 W)1,3001,300
Dishwasher (cool dry)540216
Light fixtures (5-10)1,1001,100
Garage door opener1,420720

You can figure out the right size of generator you need by following these simple steps- 

  • Make a list of the appliances in your home you want to run during an outage. 
  • Find out the running and starting wattage of those appliances. You can get the numbers on the label of each device in your home. 
  • Now, finally, count out the wattage all together to determine the generator size that you need. 

Remember, this process will give you the estimated wattage only.  For a perfect calculation, you can ask help from a professional electrician. 

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What size generator do I need for a 1,500 square foot house?

Generally, a 2200 watts to 4000 watts generator will suit a 1,500 square feet house based on the appliances you want to run through power-cut. And, if you won’t run the air conditioner and only use the daily essential equipment, you should go for a 2250 watts inverter. 

Should I use the sizing calculator for determining the size of the right generator?

It is all right to use a sizing calculator to select the appropriate one. But, it is wise to go for proper research first. Though you’ll get an estimated result from a sizing calculator, it won’t give you guidance on your requirement, budget, and features of different sizes of the generator. 

How big a generator do I need to run AC?

If it is a 2 ton (10Amp) air conditioner, a 5 KVA generator will suffice. For 3 ton (30 Amp) AC, a 14KW generator will be perfect. For a 4 ton (40 Amp) air conditioning, you would need a 17 kW generator. And, if yours is a 5-ton (50 Amp) AC, go for a 20KW generator. 

How expensive are generators?

5-12 KW comes between $3k and $5k. 12-20KW or mid-sized generators are available within $5k to $20,000. And, larger converters, 20-50 KW generators will be between $5k and $20k.

What appliances will a 10 000 watt generator run?

While you want to run conservatively most of the appliances of your home, starting from the small one to the refrigerator, air conditioner, sump pump, washing machine, and microwave oven, etc. a 10,000-watt generator will do that for you without any issue.

Final Thoughts

An alternator power supplier is all about electrical output; there is nothing to do with exterior dimensions. Too smaller size means lower wattage compared to the requirement of your home appliances can cause overload for the machine. As a result, it can get switched off automatically, or make noise or create other issues. 

On the other hand, bringing home the large one without research can cost a lot of money and require more maintenance. 

So, it is very imperative to know how many watt generator do I need for a whole house backup. Simply follow our tips and choose the right one for you.