When your power goes out, whether due to a storm or grid failure, time seems to stop. There's the mad scramble to put all perishable food into coolers, find flashlight and lantern battery replacements, and set up your phone hotspot. However, if you install an automatic generator that can power your whole home, those worries will be a thing of the past. If you live in an area prone to heavy storms, power surges, or high winds, investing in a backup generator might be something to think about. In fact, it's such a good idea everyone would have one if the home generator cost weren't so high.
But how much does an automatic backup generator cost actually? Unlike storebought portable generators or smaller backup systems that you can set up yourself, a whole house generator is a larger system that requires professional setup and installation. According to the renovation resource site Angi, the average all-in cost for a home generator system is between $1,471 and $8,340, with homeowners spending $4,906 on average. Ahead, we break down the most common home generator costs you can expect when buying and installing a whole-home generator, as well as a few factors to consider when you're shopping and getting estimates from electricians.
What Size Generator Do You Need?
Before you can purchase and install a home generator, you have to determine what size generator you need. Measured in watts (or kilowatts), a generator's output is directly related to the size and energy usage of your home. A standby generator with about 25 kW can power a 2,500-square-foot home. While it's always best to get a professional opinion, you can estimate that 1 kilowatt can power 100 square feet. At Home Depot, a 7,500 watt whole-home generator costs $2,000.
Common Generator Costs
Buying a generator and having it installed aren't the only expenses to keep in mind. Running your generator when needed will also add to your energy bill.
Product
A typical whole home generator will cost between $1,458 and $8,239 without installation or maintenance. Whole home generators can be purchased from a hardware store or retailer, but they require an electrician or other professional installer.
Installation
A standby generator's installation cost averages $4,520, which includes permits, assembly, placement, and wiring. Permanent generators require a constant fuel source, typically propane or natural gas. You can expect to pay $15 to $20 per linear foot for a natural gas line hookup during installation.
Since whole-house units are permanent and hardwired to your electrical panel, they require transfer switches to function properly. It will take a local electrician about four hours to handle this wiring, so you can expect about $1,200 of your generator installation cost to go toward transfer switch installation (aka your electrician's labor charge).
Maintenance & Use
You can anticipate an additional $80 to $300 in maintenance costs for a home generator per year. You'll need to hire a generator service pro near you to inspect it before winter and summer to ensure that it's ready to run problem-free.
You'll also want to budget between $500 to $3,000 per year ($90 to $200 per day of use) to run a 15- to 20-kilowatt whole-house generator. But not all fuels are alike, and depending on the brand and fuel you choose, you might find yourself spending far more than you expected in fuel costs.
- Natural gas: $2,000–$21,000 per year
- Liquid propane: $2,000–$21,000 per year
- Diesel: $3,000–$20,000 per year
- Gasoline: $500–$3,000 per year
Kate McGregor is House Beautiful’s SEO Editor. She has covered everything from curated decor round-ups and shopping guides, to glimpses into the home lives of inspiring creatives, for publications such as ELLE Decor, Domino, and Architectural Digest’s Clever.
