What Size Generac Generator Do I Need

You've decided that you're set up to invest in a standby generator, or a permanent unit capable of powering your essentials during an outage.

Y'all considered a less expensive portable unit of measurement or another low wattage standby, simply yous fear the smaller generator may not have the power you need to support your wattage.

But how much wattage do y'all actually need— and what size home generator exercise yous need to fuel your business firm-full of electronics?

We're here to help you choose the right size generator for your electrical needs.

How Many Watts Exercise You Need?

The first step in choosing your ideal dwelling house generator size is to brand a list of all the electronics you'd like to power during the outage.

Jot down some bullets with the essentials first, such equally keeping your fridge running, a few lights on and your AC pumping (hither in Florida, this is a must!). Adjacent to that, create a column of "nice-to-haves," similar powering your hair dryer or microwave, etc. If you'd like the luxury of having everything run as normal, sharpen your pencil and marking down all the items you'd use in the consequence of a few-day outage.

Adjacent to each particular you lot wrote down, jot downward 2 numbers: the starting wattage and the running wattage of each particular. These calculations are the amount of juice you need to get the device on as well as how much energy you'll need to keep them powered.

Not sure how many watts your hot water heater or TV requires? Honda compiled a listing of common household electronics to help you determine your generator wattage. Or, type in your appliance type on Free energy.gov to discover each device's wattage rating manually.

Generator Sizing Guide

Don't Forget Your Automated Transfer Switch

Now that yous take a list of all the electronics in your firm and their wattage requirements, y'all can start doing some math. Simply kickoff, let's not forget to gene in your automated transfer switch (ATS), if y'all accept one.

While some generators need to be manually turned on in the event of an outage, many standby units tin can find a disruption in electric current all on their own, and kick on automatically with the assistance of an ATS.

This switch needs juice to operate— usually the equivalent of your breaker panel's amperage. For example, if yous have a 200-amp breaker console, then y'all'll likely have a 200-amp switch to friction match.

Since amps are non the same as watts, y'all'll need to do a lilliputian conversion: watts = amps × volts.

Once you've adamant the wattage of your ATS, tack that onto your list and practise some unproblematic improver to discover your necessary wattage load.

Generator Sizing Guide

A Generator Sizing Scenario

Let'southward walk through a fictitious situation to help you calculate your abode generator's wattage requirements.

Scenario 1:

The Smiths take very different ideas almost what they would like powered during an outage.

Mr. Smith only wants to power the "essentials" and he made the following wattage list to keep his Fort Myers domicile running in the event of a few-twenty-four hours outage:

Electronic	Wattage
2 calorie-free fixtures	175W (far less if they are using LED bulbs)
Electrical water heater	4,000W
Key A/C	four,500W
Refrigerator	1,500W
Phone and tablet charger	50W
Total WATTAGE:	10,225W

Scenario 2:

Mrs. Smith, yet, wants to relish more luxuries if the ability were to exist out for many days in a row! She doesn't want to exist without entertainment, her kitchen or basic domicile care tech similar her washer and dryer.

Here's Mrs. Smith'due south list:

Electronic	Wattage
fifteen light fixtures (all the lights in their home)	one,225W
Electric water heater	4,000W
Central A/C	4,500W
Fridge	1,500W
Telephone and tablet charger	50W
2 laptop computers	150W
Microwave	1,000W
Stove/range	3,000W
Dishwasher	i,500W
Clothes washer and dryer	three,000W (collectively)
3 LCD TVs	450W
WiFi and cable modem	40W
Garage door opener	2,300W
Total WATTAGE:	22,715W

Now that they've adamant their wattage in "watts," the Smiths must convert their power requirements into kilowatts.

Watts vs. Kilowatts

Habitation generators are sold in measurements of kilowatts, which is why the Smiths accept to do i final conversion to find the right home generator size.

Google provides a nice tool for converting Westward or kW when yous search watts vs. kilowatts. Using Mrs. Smith'due south example above, we can come across that 22,715W would require 22.715 kilowatts. And then all you have to do it swap your comma for a catamenia, equally it'due south a 1,000 to 1 ratio.

If Mr. Smith had his manner, he'd only need a 11 or 12 kW generator to power his 10,225W load (it's always safer to add an extra kilowatt or two just in example!). If Mrs. Smith got to choose, they'd need a 25 kW abode generator.

And that's information technology! At present yous know how to summate your domicile generator wattage requirements and cull the correct sized generator for your electric needs.

More Decisions: Fuel Blazon, Brand & More

Fifty-fifty though y'all've figured out how to determine your home's generator wattage requirements, that's not all you lot have to consider before purchasing a new power unit.

Practise y'all know if you lot'll become a propane vs. gas generator? How about much your generator cost volition increase as your wattage requirements too increases? And then at that place's another large decision: which brand do you choose?

Nosotros discuss all of these things and more on our Choosing a Domicile Generator page. Simply click the image below for free advice from your friendly Southwest Florida electricians at SWFL Electric.

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Topics: Domicile Generators, Standby Generators, Generator Size