How many outages until your
whole-house generator pays for itself?
A 22kW Generac runs $10K-$15K installed. Whether it's worth the spend depends entirely on how often your power actually goes out and what each outage costs you (spoiled food, hotel stays, missed work, water-damage from sump-pump failure). This calculator stacks the numbers.
Generator installed cost ($)
Annual maintenance ($)
Outages per year
Avg hours per outage
Cost per outage to you ($)
Ownership horizon (years)
Per-outage cost: spoiled fridge/freezer ($150-$300), hotel night ($120-$200), missed work hours, sump-pump failure damage if applicable.
SKIP / RECONSIDER
Break-even beyond your ownership horizon, or lifetime ROI negative. A portable generator (~\$800-\$1,500) or battery backup is the rational path.
Outages to break even
27
cumulative
Years to break even
20.0
at your outage rate
Annual net value
+$600
outage value − maintenance
15-yr net
-$3,000
-25% ROI
Math: break-even years = generator_cost ÷ (outages × cost_per_outage − annual_maintenance). At 2 outages/yr × $450/outage − $300 maintenance = $600/yr net → break-even 20 years on a $12K generator. Most US households with 1-2 outages/yr see 15-25 year break-even, pure-cost rationale rarely justifies a standby generator outside the Gulf Coast / hurricane belt.