How Much Does a Whole-House Generator Cost? An In-Depth Analysis

How Much Does Whole-House Generator Cost

The typical whole-house generator cost ranges from $1,500 to $15,000, with most homeowners paying $4,800. We’re going over the factors that influence the cost of a standby generator for your home, including the power capacity, brand, and installation costs.


The Rise in Popularity of Whole-House Generators

In the last 20 years, the number of homes with whole-house generators has risen from less than 1% to almost 6%. Extreme weather events and increased demand on power grids have contributed to the popularity of whole-house generators. 

Experts in the industry attribute the rise in popularity to several other factors, including the number of people working from home and the increased number of people with electric vehicles and critical medical devices. 

Having a standby generator for your entire home isn’t just for storms anymore, although people who live in hurricane-prone regions like here in Florida are often more driven to purchase whole-house generators than others. More and more, people purchase one simply for the peace of mind they provide.

Factors in Calculating Whole-House Generator Cost

whole home generator

Several factors influence the cost of home generators. When selecting a unit for your home, the power capacity, brand name, and installation costs are the primary factors to consider. Here’s a rundown of each of those considerations so you know what to look for.


Power Capacity (kW)

The size of a generator, also referred to as its power capacity, is a primary determiner of home generator cost. Whole-house generators are typically sized from 9 to 48 kilowatts (kW). The average home uses 30 kW per day, or about 900 kW per month.

The higher the power capacity, the more a generator costs. Here’s a breakdown of the average costs of typical generator sizes:

Power capacity (kW)Average cost
1 to 10 kW$500 to $3,500
14 to 18 kW$4,000 to $5,500
20 to 24 kW$5,000 to $6,500
26 to 32 kW$6,500 to $15,000
36 to 48 kW$14,000 to $21,000

Brand and Manufacturer

A few name brands stand above all others when it comes to generators. Generac, Briggs & Stratton, Champion, Honda, and Cummins are among the highest-rated generators for whole-house use.

These top-name brands offer various sizes of generators, starting at about $1,300 for Honda generators. Generac is the leading manufacturer of whole-house generators, with a wide range of products available. Their lowest-priced generators start at around $6,000.

Installation Complexity

Installation costs vary depending on several factors. Some municipalities require permits for generator installations, typically running between $50 and $200.

Choosing the best spot for your generator will lower installation costs. The best spot for your generator is near your electric panel, and you could incur extra costs if it has to be farther away.

The average installation cost for a whole-house generator is $1,500 to $5,000. Many contractors will charge a flat rate for whole-house generator installation, and it’s crucial to know what is involved in the installation to avoid hidden costs.

Additional Costs and Considerations

Generac Home Backup Generators

Site Preparation and Foundation

Site preparation involves creating a place for your generator and the fuel storage tank. Whole house generators aren’t portable and require a heavy-duty concrete pad to prevent vibration. 

Concrete pads protect the unit from weather damage. The concrete pad costs $50 to $75 per square foot but could be included if your installer charges a flat installation fee.

Electrical Wiring and Transfer Switch Installation

Unlike a portable generator, a whole-house generator is designed to be installed permanently, with wiring that goes directly to your electric panel. That way, when the power goes out, you only have to flip the generator switch, and you’re set to power your house on standby mode.

An electrician will have to install a transfer switch in your home. The transfer switch prevents electricity from traveling in the wrong direction, protecting your home and generator. The average cost of a transfer switch installation is about $1,200 and takes three to four hours to install.

Electric wiring costs for standby generator installations vary depending on how far away the generator is from the electric panel and the size and type of the generator.

Fuel Source Setup (Natural Gas, Propane, Diesel)

The type of fuel you choose will affect the cost of fuel storage setup. Homes connected to natural gas infrastructure will pay much less for installations than homes that require a diesel tank setup, for example. 

Various types of fuel sources have different requirements. For example, many propane companies lease their tanks for $50 to $250 annually and install and maintain the tank without charging you extra.

Whole-House Generator Cost by Fuel Type

types of generators

The cost of whole-house generators can vary widely depending on the type of fuel used for power. Here’s a look at the cost of whole-house generators by various fuel types.

Natural Gas Generators

A natural gas whole-house generator connects to your house’s existing gas line, so it doesn’t require additional fuel storage.

Pros, Cons, and Cost Estimates

A natural gas generator is one of the least expensive to operate, at about $90 per day. They are more environmentally friendly, but they require more maintenance.  

A natural gas whole-house generator costs $2,000 to $6,000, not including installation.

Propane Generators

Liquid propane generators burn fuel cleanly, but the fuel is more expensive. Installation must include a large fuel tank.

Benefits, Limitations, and Pricing

Propane generators are the best choice when you don’t have access to natural gas infrastructure. However, the engine has a shorter life expectancy, and costs about $200 per day to operate.

A propane gas whole-house generator costs $2,000 to $6,000, not including installation.

Diesel Generators

Diesel, while still explosive, is much safer than other types of fuel. It’s also more efficient and reliable than propane or natural gas.

Features, Potential Issues, and Cost Ranges

Diesel generators can run longer and provide more energy than other types of generators, so they’re often chosen for remote locations and off-grid applications. 

A diesel whole-house generator costs $5,000 to $18,000, not including installation, making it the most expensive type of generator.

Do I Need a Whole-House Generator?

how much whole home generator

Are you having trouble deciding if you should pull the plug on a whole-house generator? Here are a few things to think about to help you decide.

Increased extreme weather events across the United States are leading to more power outages. If you’re in a region prone to power outages, that’s a good reason to consider a whole-house generator. 

Assessing Personal Needs and Dependence on Power

Nobody but you knows your personal needs, and there are many valid reasons for a dependence on power. For example, if you have a CPAP machine or an electric car, having a whole-house generator is more critical for your health and well-being.

Financial Cost-Benefit Analysis

A whole-house generator’s average return on investment is about 150%, so it’s an excellent way to build equity in your home. 

To do a cost-benefit analysis, brainstorm the benefits and assign each benefit a monetary value. After you analyze the cost of installing a whole-house generator, it’s easier to compare the two values to help you decide if it’s worth it.

What Size Whole-House Generator Do I Need?

Generac dual fuel backup system

Calculate your home’s energy consumption to determine what size generator you need.

Calculating Your Home’s Energy Consumption

Conducting an energy audit of your home is always an excellent idea. To determine your home’s energy consumption, list all the electrical appliances you need to operate with your whole-house generator.

Importance of Sizing for Peak Loads

Understanding the importance of sizing for peak demand hours is critical. Add up all of the appliances that will be used during peak demand hours.

Future-Proofing: Planning for Additions or Increased Usage

It’s smart to size your generator to plan for increased usage as time passes. Once you’ve calculated the peak load, add an additional 20% to 25% to account for potential additions to your home or family.

DIY Whole-House Generator Installation vs Hiring a Professional

professional installed whole home generator

DIY generator installations are not typically a DIY-friendly project. Instead, this is a job for a licensed electrician or contractor. 

Whole-house generator installation involves specialized knowledge about plumbing, electricity, placement, and permits. In many municipalities, you will also be required to confirm through the permitting process that a licensed electrician is hooking up your emergency standby generator.

As a homeowner, understanding the installation process is critical because it helps you make the right purchasing decision. 

How to Save Money on Whole-House Generator Cost

Use these money-saving tips when shopping for a whole-house generator.

Seasonal Shopping: When to Buy a Generator

You can save up to half the price of a generator by shopping during the off-season, but the best time to buy a generator depends on where you live. 

If you live in Hurricane Alley, you’ll need a generator from June to November, but if you live in the colder regions in the northern parts of the United States, you’ll want a generator during the opposite time of the year. Try to time your purchase so you’re not buying when demand is at its peak.

Take Advantage of Manufacturer Promotions or Rebates

When shopping for expensive items like generators, it pays to look for manufacturer promotions and rebates. You may also qualify for a rebate for a generator from your power company.

Maintenance and Longevity: Getting the Most from Your Investment

Taking care of your generator will ensure that you maximize the life expectancy, which is typically about 20 to 40 years, or between 10,000 and 30,000 hours of run time. 

It’s a good idea to purchase a DIY generator maintenance kit for $20 to $110, and follow an annual maintenance schedule, addressing these common maintenance tasks:

  • Change air, fuel, and oil filters
  • Flush fuel tanks
  • Inspect crankcase breathers
  • Clean or replace spark plugs
  • Test and replace belts and hoses 
  • Check and refill oil

In addition, stay in compliance with your warranty by performing routine maintenance after every 100 hours of use and recording the results of your inspections. You can also sign up for annual maintenance contracts, which cost about $200 to $650 per year.

The Assurance of Continuous Power in Uncertain Times

As more and more extreme weather events leave people feeling vulnerable about power outages, it’s no mystery why there’s a rise in the popularity of whole-house generators.

When you have to hunker down, there’s no place like home, and having a reliable source of continuous power, regardless of external factors, provides a peace of mind that can’t be matched. 

Frequently Asked Questions About Whole-House Generator Installation

How often will I need to maintain my generator?

Like all major equipment, whole-house generators require regular maintenance. You should use an annual maintenance checklist for routine maintenance tasks like spark plug replacement and oil changes, and then be sure to follow the manufacturer guidelines for maintaining your generator after 100 hours of use.

What’s the lifespan of a typical whole-house generator?

Whole-house generators are long-lasting machines. The typical lifespan of a standby generator is between 20 and 40 years, usually between 10,000 and 30,000 hours of run time.

How noisy are these generators?

The average standby generator ranges in loudness from about 50 decibels (dB) to 100 dB. While noise is a concern, it’s usually much lower than most people expect. To compare, 50 dB is about the level of a quiet refrigerator, and 100 dB equates to a hair dryer or lawn mower.

Are there environmental concerns with certain fuel types?

All types of fossil fuels contain pollutants that harm the environment and human health. Because of this, some people invest in alternative solutions like solar generators or home battery backup systems.

Can I upgrade an existing smaller generator to a whole-house unit?

A small generator that produces about 5,000 to 7,500 watts is enough to power most households, including an air conditioner, refrigerator, and television. Whether or not you can upgrade an existing small generator to use as a whole-house generator depends on the energy needs of your house and what you absolutely need to power during an emergency. 

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