The number, straight
What a Whole-House Generator Costs in Maine
Most whole-house standby systems in Greater Portland cost $8,000 to $15,000 installed, complete. This page breaks down exactly where that money goes and what makes your number land at the bottom or the top of the range, so a quote reads like information instead of a mystery.
Free estimates · Written pricing · No oversizing, ever
The Real Ranges, Installed
- Essentials-only systems (10 to 14kW): roughly $6,000 to $9,000 complete. Heat, well pump, sump pump, refrigeration, kitchen and some lights. The safety-first budget option that handles a Maine outage's actual dangers.
- Whole-house air-cooled systems (18 to 26kW): roughly $8,000 to $15,000 complete. The sweet spot for most Greater Portland homes: every circuit covered, one-day install.
- Large-home and liquid-cooled systems (30kW+): $18,000 and up. Big square footage, pools, elevators, multiple heat-pump arrays, or estate-scale electrical services.
Where the Money Actually Goes
- The generator itself is typically only 40 to 55 percent of the total. A 22kW unit lists in the $5,000 to $7,000 neighborhood before anything touches your house.
- Automatic transfer switch: the brains of the system, wired into your panel by a Maine-licensed electrician. Hardware plus skilled labor.
- Fuel work: tying into natural gas, or setting and plumbing a propane tank. Long pipe runs and high-demand units push this line up. This is the most commonly underestimated line item.
- Site prep and placement: pad, code-required clearances from windows and vents, and sometimes crane time when the only spot is behind a fence.
- Permits, inspection, and startup: the boring paperwork that makes it legal, insurable, and warrantied. If a quote skips this line, that's not a discount; it's a red flag.
What Moves Your Number Up or Down
- Distance: feet of wire and feet of gas pipe between the unit, the meter, and the panel are the quiet multipliers.
- Fuel situation: natural gas at the house is the cheap path; a new propane tank adds cost but works everywhere.
- Electrical service condition: older panels sometimes need work before a transfer switch can go in. Better to learn that at the estimate than on install day.
- Coverage choice: essentials-only vs. whole-house is a several-thousand-dollar decision, and honest sizing beats big sizing. (The homepage's sizing section covers this.)
- Brand: Generac and Kohler price within shouting distance of each other; the house drives the number more than the badge does.
The Cost Nobody Puts on a Quote
Now the other column: a multi-day winter outage without backup power. Frozen and burst pipes routinely run five figures with drywall and flooring. A flooded basement when the sump pump died in a spring storm: four to five figures plus the mold remediation. A freezer of food, hotel nights, lost work days for a home office. Southern Maine reliably produces the outages that produce those bills. A standby system is the version of that money you spend once, on purpose, and it's why the payback question usually answers itself the first time the machine runs for real. When you're ready for a number specific to your house, the estimate is free, written, and comes from a Maine-licensed installer, with annual upkeep priced up front too, so there are no surprises later.
Common questions
Generator Cost FAQs
Can I save money by buying the generator myself and hiring an installer?
Usually not as much as people hope, and sometimes nothing. Package pricing through an installer typically includes the unit at competitive cost plus the parts of the job you can't buy at a box store: correct sizing, gas work, licensed electrical, permits, startup, and someone who owns the whole outcome. A box-store unit with no installer attached also tends to wait in the garage a surprisingly long time.
Does a whole-house generator add home value?
In outage-prone markets like southern Maine, yes: buyers understand exactly what it means, and appraisers increasingly do too. Industry estimates generally put recovery at a meaningful fraction of the installed cost, plus faster sales in storm-aware neighborhoods. It's one of the few mechanicals a listing agent will lead with.
What are the ongoing costs after installation?
Three things: fuel when it runs (natural gas on your utility bill, or propane from your tank), annual service in the $200 to $400 range to keep the warranty valid, and eventually a battery every few years. Weekly self-tests use a negligible amount of fuel. There are no subscriptions required, though remote monitoring apps are available.
Is a portable generator a cheaper alternative?
Cheaper up front, absolutely: a decent portable costs a fraction of a standby system. But it starts nothing automatically, backfeeds nothing safely without a transfer switch, runs hours per gas can you fetch in the storm, and can't carry a furnace, well pump, and sump pump together. For camps and short outages, portables make sense. For a primary residence in an outage-prone area, they're the reason standby systems exist.
Get your real number, in writing
Free on-site estimate: load calculation, fuel check, and a complete written price for your house. The ranges on this page end where your driveway starts.