Buying Decision
Is a Whole-House Generator Worth It?
The honest answer is: it depends on three things — how often your power actually goes out, what you’re protecting when it does, and how long you’ll stay in the home. Here is the real 20-year cost, the value on the other side of the ledger, and a framework to decide.
What it costs to get in
A 22kW Generac Guardian — the right size for most Chicago-area homes — installed starts around $12,000 for a standard whole-home job, plus a permit. Some homes need one-time site work on top — a 200A panel upgrade ($1,800–$3,000), a long gas run, or difficult pad access — which is why the cost guide breaks the drivers out. That upfront number is the biggest single cost of ownership; almost everything after it is small by comparison. What sits on the other side of the ledger is easier to judge against the dated outage record than against a general sense that storms happen.
The 20-year cost of ownership
Air-cooled standby generators typically last 15–25 years with proper maintenance, so 20 years is a fair window. Here is what a typical 22kW whole-home unit costs across that span — ranges, not false precision.
| Cost category | Cadence | 20-year | Notes |
|---|---|---|---|
| Equipment + standard install (22kW whole-home) | once | ~$12,000 | Chicago-area starting price; equipment, labor, transfer switch, standard site conditions. |
| Permit + inspection | once | ~$85–$435 | Varies by municipality (e.g. Naperville $85; DuPage unincorporated $295–$435). |
| Maintenance (dealer plan or annual service) | $150–$400 / yr | $3,000–$8,000 | Dealer plans commonly $175–$300/yr; oil, filters, plugs, battery, ATS test. |
| Fuel (weekly exercise + outage hours) | usually $10–$60 / yr | ~$200–$1,200 | Small because the unit runs few hours a year — see the worked example below. |
| Post-warranty repairs + battery (yrs 6–20) | occasional | ~$1,000–$3,000 | Batteries every ~3–5 years plus the odd part after the 5-year warranty. Estimated. |
| 20-year total (base, no major site upgrades) | ~$16,000–$25,000 | Roughly $800–$1,250 per year of whole-home standby protection. |
Install price: Chicago-area starting cost (see cost guide). Maintenance $150–$400/yr: Angi 2026 whole-house generator maintenance data + published dealer plan pricing. Lifespan 15–25 years and post-warranty repair/battery costs: multiple installer/industry sources [OBSERVED]. Repair and fuel lines are estimates, labeled as such.
Why fuel is the smallest line item
The common fear is that a standby generator is expensive to run. It isn’t — because it runs so little. At heavy load a unit this size burns roughly 300 cubic feet of natural gas per hour (about 3 therms). At Nicor’s residential gas-supply rate — which ran about $0.36–$0.54 per therm across 2025–2026, with delivery on top — that is on the order of $1.50–$2.50 per hour at heavy load.
But the unit only runs a brief weekly exercise cycle (minutes) plus whatever outage hours your year actually brings. A quiet year costs a few dollars; only a long multi-day outage adds up — and in that outage the generator is doing exactly what you bought it for. For live prices, check Nicor; the fuel-vs-power tradeoff is covered on our natural gas vs. propane page.
Consumption ≈ verified spec-sheet figures (Generac 24kW 306 cfh; Kohler 26RCA 290 cfh). Gas rate: Nicor Gas / Citizens Utility Board 2025–2026. Runtime is illustrative, not a fixed cost.
The other side of the ledger
ROI on a generator isn’t a stock return — it’s avoided loss and avoided misery. In the Chicago suburbs, the biggest number is usually the one nobody quotes: a flooded basement.
Sump pump & basement flooding
The single most valuable thing a generator protects here. DuPage and Will County clay soils push water against foundations, and the storms that knock out power are the same storms that flood basements — the City of Naperville itself recommends backup power for sump pumps. One finished-basement flood can cost far more than a year of the generator. Exposure is very local: the Salt Creek corridor is why Elmhurst built the Elmhurst Quarry flood-control facility and why flooding around Graue Mill is a recurring problem in Hinsdale.
Food safety
USDA/FSIS guidance: refrigerated food is unsafe after about 4 hours without power, and a full freezer holds roughly 48 hours (24 if half-full). A single multi-day outage can spoil hundreds of dollars of food.
Frozen pipes, medical needs, remote work
A winter outage can freeze and burst pipes; a home medical device or a work-from-home income can’t wait on ComEd’s restoration queue. These are the outages where a generator stops being a convenience and becomes essential.
Resale value
National resale studies (Remodeling magazine’s Cost vs. Value work) put recovery at roughly two-thirds of a standby generator’s installed cost, with higher recovery in outage-prone markets. It won’t pay for itself at closing, but it recovers a meaningful share and is a genuine listing feature here.
Food-safety windows: USDA Food Safety and Inspection Service. Resale recovery: Remodeling magazine Cost vs. Value (national; varies by market). Flood-risk context: DuPage County stormwater + City of Naperville sump-pump guidance (see facts on our city guides).
So — is it worth it for you?
Usually worth it if…
- ✓You’ve lost power for a full day or more in the last few years (the 2020, 2021, and 2024 storms all did this across the western suburbs).
- ✓Your basement depends on a sump pump — DuPage/Will clay soils flood in the same storms that cut power.
- ✓Someone in the home relies on medical equipment, or you work from home.
- ✓You’re on a well (no power, no water).
- ✓You plan to stay 7+ years, so the cost spreads over many outage seasons.
- ✓Your home and its contents are high-value — more to protect, and better resale recovery.
Think twice if…
- •Your outages are rare and short (an hour or two, a couple times a year).
- •You’re likely to move within a year or two.
- •You have no basement or no sump/flood exposure.
- •Your critical loads are minimal and a portable unit or battery could cover them — see whole-house vs. portable for how that choice plays out here.
Why the math tilts positive in the western suburbs
The ROI question is really an outage-frequency question, and this market answers it. The August 2020 derecho left roughly 58,000 DuPage County homes dark for up to five days; a June 2021 EF-3 tornado and a July 2024 derecho each put tens of thousands more into multi-day outages. Add the sump-pump flood exposure that comes with the same storms, and the value a generator protects here is unusually concrete — which is exactly why so many of these homes have one. See your city’s outage history and permit rules: Naperville, Aurora, Wheaton, Downers Grove, Oak Brook.
See what it costs for your home
The worth-it math turns on your home’s size, loads, and site conditions. Tell us about your home and we’ll put it in front of installer coverage in your area for a real number — no national call center.
Get quotes for your suburb
Permit fees, inspection steps and the utility you deal with change from one suburb to the next. These pages carry the local details.