What Size Generator Do I Need For 200 Amp Service?
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A 200 amp service is a lot of power. That’s why it’s extremely important to make sure you have the appropriate size generator before taking on such an installation.
In this article, we’ll give you some guidance on what size generator you need for a 200 amp service and how to get the most out of your installation.
What Size Generator Do I Need For 200 Amp Service?
For a 200 amp service, you will need a generator that can produce at least 15000 watts of power.
A generator that produces at least 15000 watts of power can produce up to 20 amps per hour, which is enough for a low-density 200 amp service.
Size | Running Watts | Recommended Generator |
---|---|---|
Minimum | 12000 | Champion 12000 Running Watts Generator |
Medium | 15000 | Generac 15000 Running Watts Generator |
Maximum | 20000 | Generac Home 19.5kW Air Cooled Standby Generator |

If you use major appliances like AC, Refrigerator, Microwave, Coffee Maker, Toaster, Electric Stove, Washing Machine, Sump Pump at a time, then you would need more than 20000 watts generator though the amp service is the same.
We made a chart for 200 amp service generators based on major appliance uses:
Major Appliances | Running Watts | Recommended Generator |
---|---|---|
10,000 BTU AC, Refrigerator – 24 Cu. Ft. (with Freezer), TV – 42″ Plasma, Microwave, Coffee Maker, Food Processor, Electric Stove – 8″, Furnace – 1/2 HP Fan, Toaster, Washing Machine, Steam Iron, Laser Printer, Electric Space Heater – 5100 BTU, Sump Pump – 1/3 HP, Garage Door – 1/2 HP. | 12000 | Champion 12000 Running Watts Generator |
10,000 BTU AC, Refrigerator – 24 Cu. Ft. (with Freezer), TV – 42″ Plasma, Microwave, Coffee Maker, Food Processor, Electric Stove – 8″, Furnace – 1/2 HP Fan, Toaster, Washing Machine, Steam Iron, Laser Printer, Electric Space Heater – 5100 BTU, Sump Pump – 1/3 HP, Garage Door – 1/2 HP, Steam Iron, Hair Dryer. | 15000 | Generac GP15000E 15000 Running Watts/22500 Starting Watts Generator |
21,000 BTU AC, Refrigerator – 24 Cu. Ft. (with Freezer), TV – 42″ Plasma, Microwave, Coffee Maker, Food Processor, Electric Stove – 8″, Furnace – 1/2 HP Fan, Toaster, Washing Machine, Steam Iron, Laser Printer, Electric Space Heater – 5100 BTU, Sump Pump – 1/3 HP, Garage Door – 1/2 HP, Steam Iron. | 17000 | Generac 7077 Guardian Series 20kW/17kW Air Cooled Standby Generator |
30,000 BTU AC, Refrigerator – 24 Cu. Ft. (with Freezer), TV – 42″ Plasma, Microwave, Coffee Maker, Food Processor, Electric Stove – 8″, Furnace – 1/2 HP Fan, Toaster, Washing Machine, Steam Iron, Laser Printer, Electric Space Heater – 5100 BTU, Sump Pump – 1/3 HP, Garage Door – 1/2 HP, Steam Iron, Hair Dryer, Laser Printer, Garage Door. | 19500 | Generac Home 22kW/19.5kW Air Cooled Standby Generator |
What To Look Before Buying A 200 AMP Service Generator?

If you need a generator for 200 amp service, what should you be looking out for?
There are important features and factors you need to consider before buying this type of equipment. Here is the checklist:
1) Fuel Tank Capacity
When there’s insufficient fuel supply, the generator will not be able to run, even if it is already turned on.
When you fill up your tank for the first time, don’t forget to put in a fuel stabilizer and additive.
This way, the gasoline won’t get contaminated when the temperature changes rapidly or reaches freezing point.
There are two types of fuel tanks: portable and stationary. Portable fuel tanks are mounted behind the generator and can be filled from a nearby gas station.
Stationary fuel tanks, on the other hand, are permanently installed in your home’s or office’s backyard.
2) Transfer Switch

A transfer switch will allow you to convert your portable or stationary generator into an uninterruptible power supply (UPS).
This also allows you to transfer the load on your generator to a backup source of power provided by your utility company.
3) Portable or Stationary Generator
Aside from these features, a portable and stationary generator will each have its own benefits.
A portable generator may be operated at different locations while a stationary one would need to be permanently installed in the backyard.
A portable generator boasts of being lightweight, easy to move around, and can be used to power up your home appliances when there’s an upcoming storm or emergency.
However, it has a low fuel economy since energy is lost in the transfer switch (up to 20%).
If on a tight budget, you might want to buy a cheaper portable generator. This way, you can still use it for home and office backup without spending a lot.
The only disadvantage of using portable generators is that they’re not as efficient as stationary ones when your power needs are bigger than what portable generators can provide.
Portable generators don’t have a high fuel economy since energy is lost in the transfer switch (up to 20%).
A stationary generator is ideal if you want a backup system that is long lasting and provides good value for the price.
Purchasing a permanent installation, on the other hand, won’t make you worry about storage or transportation during emergencies.
You can also customize its features to meet your power needs since it’s already permanently installed in your home or backyard.
However, you should consider the size and location of your installation as well as how it will affect the surrounding landscape.
Keep in mind that a permanent generator may be less expensive to purchase than a portable one but could cost you more when it comes to installation and maintenance fees.
4) Fuel Economy

According to the International Energy Agency, the world will be using more energy in the next few years.
Most of this energy will come from fossil fuels. Despite the negative impact of burning fossil fuels on our environment.
Sustainable sources like solar and wind power are not yet cost-efficient. With that said, we still have to rely on electric generators sooner or later.
Because of this, it is important to look for a generator with efficient fuel consumption.
Fuel economy is calculated by dividing the electricity delivered by the amount of fuel consumed.
A portable generator that uses fewer fossil fuels will work longer between refueling while lowering your electric and heating bills.
>> What generator size to power 5 ton ac?
5) Noise Level
Compared to other power sources like solar panels, a portable generator may be the only alternative during power outages.
You’ll probably want to get one that’s as quiet as possible so you can use it at any time of the day or night without disturbing your neighbors.
6) Power Output and Capacity
As I said earlier, there are two types of generators: portable and stationary. Stationary generators have capacities ranging from 1 to 10 kilowatts.
The power output of a portable generator ranges from 0.25 to 4.5 kilowatts for most models on the market today.
The capacity refers to the maximum amount of power that your generator can deliver at any given time under normal operating conditions while the power output simply describes how powerful a generator is.
The capacity of your generator refers to the maximum amount of power that it can deliver under normal operating conditions while its output is simply the total amount of power produced by your electric generator at any given time during operation.
Best Generator For 200 AMP Services
1. Champion Power Equipment 15,000/12,000-Watt Portable Generator with Electric Start and Lift Hook

The Champion Power Equipment 100111 15,000/12,000-Watt Portable Generator is a great product for those wanting to bring the power of their house with them.
This generator provides an amazing amount of watts that can be used up at home or on the go.
With no need for fuel oil, this generator will take care of everything you need.
This Champion Power Equipment Portable Generator features a gas powered engine that runs smoothly and quietly for hours at a time.
With a weight of 330 pounds, this generator is light enough to move around with ease.
This product also features an intelligent gauge that lets you monitor voltage, hertz and run-time hours so your power needs are met on the go or at home.
The Champion Power Generator includes four 120V 20A GFCI outlets that are protected by a safety system.
In addition, this product features two regular and one locking 220v 30 amp outlets for those with larger needs.
This Portable Generator also includes an easy access side door to the fuel tank reservoir. This allows for quick and easy refueling.
The Champion Power Equipment 100111 Generator is a great product that offers more than enough power for those who may need it on the go or at home.
The generator features nine hours of run time when used with an empty tank which provides plenty in an emergency.
This Generator is great for those who need a lot of power and with its three year limited warranty, you are guaranteed to get your money’s worth!
2. Generac GP15000E 15000 Running Watts/22500 Starting Watts Electric Start Gas Powered Portable Generator

The Generac GP15000E Gas Powered Portable Generator is a powerhouse for the heavy-duty power needs of today’s homeowners.
This generator is capable of supplying up to 22500 starting watts and 15000 running watts. Perfect for disaster preparedness in your home.
This Generator features a heavy-duty steel frame and 16 gallon fuel tank for up to ten hours of run time at 50% load, as well as an idle control that reduces noise and conserves fuel.
The generator is equipped with 120 volts and has two 3000 watt outlets (one L14-30R twist-lock and one L14-30P plug), which are capable of handling all your household needs.
The generator is engineered with a low oil-level shutdown and hour meter to ensure your peace of mind.
Included are two 12V outlets, one 120 volt outlet (L14-30R twist lock) and four heavy duty rubber feet for ultimate stability on the Jobsite or in other demanding environments.
The Generac GP15000E Gas Powered Portable Generator is backed by a two-year warranty on parts and labor as well as an additional year of protection against power outages so you can be confident in this purchase.
It has a 992cc OHVI engine that provides plenty of power for the toughest job sites.
This generator is also equipped with an electric start, so you can get back to work as soon as possible without wasting precious time cranking a hand crank.
3. Generac 7077 Guardian Series 20kW/17kW Air Cooled Standby Generator with Aluminum Enclosure – 3 phase

The Generac Guardian Series is the perfect generator for any homeowner.
This series provides 20kW and 17kW models that are capable of powering an average home with 200 amp service during a blackout or power outage.
As well as provide emergency backup when camping, boating, hunting or using other recreational vehicles.
The Guardian Series is equipped with a variety of features that will make your time without power as smooth and comfortable as possible, while also helping to extend the lifetime of sensitive electronics.
The Generac 7077 guardian series comes in a 20kW/17kW Air Cooled Standby Generator for 200 amp service.
The generator has an automatic transfer switch (Sold Separately) and has a tough, durable all-weather aluminum enclosure with removable sides for easy access.
It includes Generac’s ‘TruePower Technology’ which delivers best in class power quality while delivering smoother operation of sensitive electronics and appliances.
The generator also offers a variety of useful features that can be easily controlled via the Generac evolution controller.
The features include generator status, utility power presence or maintenance required which are all visible on LED indicators.
Pros: This series offers two sizes of generators that can handle most households’ needs with 200 amp service and provides emergency backup when camping, boating, hunting or using other recreational vehicles.
The generator is also equipped with a variety of features that will make your time without power as smooth and comfortable as possible, while also helping to extend the lifetime of sensitive electronics.
Cons: Some customers have noted an issue where generators won’t start when they are hot. These units should not be started until they have cooled down for a few hours.
4. Generac 7043 Home Standby Generator 22kW/19.5kW Air Cooled with Whole House 200 Amp Transfer Switch, Aluminum
The Generac 7043 Home Standby Generator 22kW/19.50kW Air Cooled is the perfect power backup for your home or office, and it includes all of the features you want in a generator!
It has a powerful engine that provides smooth operation and less than five percent total harmonic distortion (THD), which means this unit operates smoothly while powering sensitive electronics and appliances.
This generator also includes a durable, all-weather aluminum enclosure that provides three removable sides for convenient service access.
The Generac evolution controller features LED indicators for generator status, utility power presence or maintenance required.
It has a 200 amp NEMA (indoor/ outdoor rated) whole house smart transfer switch that can be mounted indoors or outdoors.
If you’re looking for a generator to use during an extended power outage, the Generac Home Standby Generator 22kW/19.50kW Air Cooled is worth your consideration!
The unit features a powerful engine that provides smooth operation and less than five percent total harmonic distortion (THD), which means this unit operates smoothly while powering sensitive electronics and appliances.
This generator also includes a durable, all-weather aluminum enclosure that provides three removable sides for convenient service access.
The Generac evolution controller features LED indicators for generator status, utility power presence or maintenance required.
It has a 200 amp NEMA (indoor/ outdoor rated) whole house smart transfer switch that can be mounted indoors or outdoors.
If you’re looking for a generator to use during an extended power outage, the Generac Home Standby Generator 22kW/19.50kW Air Cooled is worth your consideration!
Final Words
The size of the generator you need is going to depend on a few factors. For example, the wattage and voltage rating of your service will determine what size generator you need for it.
If you are unsure about how many watts or volts your service has, contact an electrician in your area who can help with this question for you.
Alongside that information, if there are any other appliances plugged into the same circuit as the one feeding power to your home then they too may be drawing current from it which means a larger sized generator would be needed than if only lights were powered by that outlet.
Finally, consider where the generator will be located when deciding its capacity (for instance; running off solar panels).