Guide to Selecting a Whole Home Generator

By April 8, 2020 February 8th, 2021 No Comments

The Complete Guide to Selecting a Whole Home Generator in 2020.

With so much uncertainty in the world today having a source of backup power is more important then ever. On any given week there are approximately 3.5 million Americans left without power because of outages. In the event your house goes “off grid” temporarily or long term a whole home generator will automatically restore power to your house as if nothing had happened.

Three Steps to Choosing the Right Generator

Generator Size
Fuel Source
Transfer Switch
Step One

Generator Size

Choosing the Right Generator Size

Selecting a generator that can produce enough energy to power all your electrical needs is arguably the most important factor of selecting the right generator. If you choose a generator that is too small, it may fail to perform when you need it most.

The first question you should ask yourself before buying a generator is which electronic devices do you want to power in the event of an outage. Do you want life to continue like nothings changed? Or do you just want to power essential systems such as heating, cooling, refrigeration, and sump pumps?

Calculating Wattage

In some cases, your appliances or electronic devices will only have the required amps or amperage and voltage rather than watts and you will have to manually convert this information into watts using the formula below.

Watts = Amps X Voltage

Example: A 20-amp clothes dryer with a 220-volt power source would require 4,400 watts to operate.

Starting Watts vs Running Watts

Many electronic devices have both a starting watt requirement to get running and a running watt requirement to stay in operation. Appliances and devices with motors typically having a higher starting watt requirement.

For example: A refrigerator typically uses around 750 watts to operate but can require up to 2000 watts to get started.

Below is the Estimate Watt Usage for Many Common Household Items

  • Refrigerator: 750 Watts
  • Microwave: 750-1100 Watts
  • Coffee Maker: 900-1200 Watts
  • Washing Machine (Clothes) 350-500 Watts
  • Dryer (Clothes) 1800-5000 Watts
  • CPU: 120 Watts
  • Laptop: 50 Watts
  • 36” TV: 133 Watts
  • Vacuum Cleaner: 1000-1200 Watts
  • Toaster: 800-1400 Watts
  • Water Heater (40 Gal) 4500-5500 Watts
  • Electric Tankless Water Heater: 6600-8800 Watts
  • Garage Door Opener: 300-400 Watts
  • LED Light Bulb: 10 Watts
  • Treadmill 280-900 Watts
  • Wall Fan: 45-60 Watts


Why you Should Purchase a Generator Slightly Larger then Your Wattage Needs. 

Many electronic devices have both a starting watt requirement to get running and a running watt requirement to stay in operation. Appliances and devices with motors typically having a higher starting watt requirement.

For example: A refrigerator typically uses around 750 watts to operate but can require up to 2000 watts to get started.

Step Two

Fuel Source

Selecting a Fuel Source for Your Generator

There are several options to choose from when selecting a fuel source for your generator system. The most common options include natural gas, propane, gasoline, and diesel fuels. Below we will review the pros and cons for each of these generator fuel sources.


Natural gas is a great option for whole home generators if available in your area. Natural gas can provide a low-cost clean burning fuel source in the event of a power outage.


  • Unlimited Fuel Source – (No refueling necessary)
  • Quieter engine noise level
  • Clean Burning


  • Higher up-front installation cost
  • May be unavailable for certain natural disasters (Earthquakes, tornados, etc.)
  • Natural gas may not be available in your area


Propane fuel can be a great for those who live in remote areas and don’t have access to natural gas. Large propane tanks can be easily rented or purchased with substantial storage capacities.


  • Long Shelf Life
  • Clean Burning
  • Easily Stored & Accessible
  • Home delivery options


  • Large propane tanks are not aesthetically pleasing
  • Shorter life expectancy then diesel fueled generators
  • Propane can be dangerous if fuel lines are broken


Gasoline is the most easily obtained fuel source and among the most common for portable generators which helps to increase the mobility of these smaller generators.


  • Increases portability of smaller generators
  • Common fuel source


  • Highly flammable
  • Short shelf life – 12 months or less
  • Can be expensive – especially during natural disasters


Diesel fuel is the least flammable fuel source and easily obtained in most areas. Diesel powered generators also tend to last significantly longer then their gasoline powered counterparts.


  • Diesel is easily obtainable
  • Can operate in artic conditions with fuel additives
  • Least flammable fuel source


  • 18-24-month shelf life
  • More engine noise then other fuel types
  • High emissions (Some area may restrict the use of diesel engines for extended periods of time)

Final Thoughts

Your specific needs will determine which fuel source is right for you for example: If you’re looking for a seamless fuel solution in town natural gas is the way to go. If you’re in a frigid climate or remote area you may consider either diesel or propane.

If you have questions about which fuel source to use, you can contact VPC Electric to guide you into making the best fuel decision.

Step Three

Transfer Switch

Choosing your Transfer Switch

What is a transfer switch?

A transfer switch is a device that “switches” an electric load between two sources. When it comes to generators these devices switch the power source to your home from grid power to your generator power.

There are two major options when it comes to selecting your transfer switch. An automatic transfer switch and a manual transfer switch.

Automatic Transfer Switches

Just like the name implies automatic transfer switches will automatically transfer your power source from the grid to your generator in the event of an outage. This transfer of power is almost seamless and requires no manual actions to implement.

This is incredibly valuable for places that rely on electricity to functions such as hospitals, data centers or residences that have electronic medical equipment.

When grid power is restored automatic transfer switches will switch your power source right back to grid power.

The only major drawback to automatic transfer switches is the increased cost to design, fabricate and install over manual transfer switches.

Manual transfer Switches 

Unlike their automatic counterparts a manual transfer switches requires a person to physically flip the switch to initiate use of the generator. The convenience tradeoff comes with a more affordable price tag which can sway generator owners to go with the manual option.

Wrapping UP

Generators come in many shapes and sizes and can fit a wide variety of power needs. Making sure you have the right generator for your needs is critical to making sure you have power when you need it most.

If you have any generator related questions please give VPC Electric a call at 844-715-7233 or email us at service@vpcelectric.com

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