Generator installation cost in Illinois
About $12,169 to $18,269 covers the installed price in Illinois for a 22 kW whole house generator burning natural gas. The US average hourly wage is $34.37, while local electricians earn $44.34, or 29% more. That wage determines the $3,900 to $7,100 electrician line.
Is 22 kW the right size for your home? Find your size in three questions.
Installed price in Illinois by size
Illinois prices and fuel at half load. Each model has a Generac fuel table. The hourly burn ratings for 18 kW, 24 kW and 26 kW stay at or below those of the next smaller size, so fuel use per hour doesn't climb in step with kW.
| Size | Natural gas, installed | Gas at half load | Propane, installed | Propane at half load | Fuel figures |
|---|---|---|---|---|---|
| 10 kW | $9,419 to $15,519 | $1.75/h | $9,819 to $16,119 | $1.89/h | Generac Guardian 10 kW |
| 14 kW | $10,749 to $16,849 | $3.38/h | $11,149 to $17,449 | $3.53/h | Generac Guardian 14 kW |
| 18 kW | $11,569 to $17,669 | $2.93/h | $11,969 to $18,269 | $3.31/h | Generac Guardian 18 kW |
| 22 kW | $12,169 to $18,269 | $3.53/h | $12,569 to $18,869 | $4.93/h | Generac Guardian 22 kW |
| 24 kW | $12,589 to $18,689 | $3.52/h | $12,989 to $19,289 | $4.93/h | Generac Guardian 24 kW |
| 26 kW | $13,019 to $19,119 | $3.26/h | $13,419 to $19,719 | $4.01/h | Generac Guardian 26 kW |
Which items make up the 22 kW price in Illinois?
Labor priced at the $44.34 hourly wage can cost up to $1,600 more than labor based on US average pay. That wage ranks 4th of 51 and is among the highest.
| Line, 22 kW | Natural gas | Propane | Basis |
|---|---|---|---|
| Generator | $6,309 | $6,309 | The 22 kW bundle at Generac list price, minus the switch |
| Transfer switch | $1,060 | $1,060 | the difference between Generac's listing that includes the switch and the one that doesn't |
| Electrician: switch, wiring, start-up | $3,900 to $7,100 | $3,900 to $7,100 | Installation ranges as published, adjusted for the Illinois hourly wage of $44.34 (BLS) |
| Fuel line | $600 to $2,600 | $1,000 to $3,200 | gas line starts at the meter, propane line at the tank |
| Pad and permit | $300 to $1,200 | $300 to $1,200 | composite pad or slab, local fees |
| Installed | $12,169 to $18,269 | $12,569 to $18,869 | propane leaves out the tank |
What fuel costs in Illinois
| Fuel | Price | 22 kW an hour | Three days |
|---|---|---|---|
| Natural gas | $17.32 per 1,000 ft³ | $3.53 | $254 |
| Propane | $1.95 a gallon | $4.93 | $355 (182 gal) |
In Illinois, a 22 kW generator at half load has a gas cost of $3.53 an hour. The propane cost is $4.93 an hour. Residential gas prices here rank 14th cheapest of 51.
| Propane tank | Usable at 80% | 22 kW at half load | Fill at Illinois price |
|---|---|---|---|
| 250 gal | 200 gal | 79 h | $390 |
| 500 gal | 400 gal | 158 h | $779 |
Power outages in Illinois
In 2025, Illinois customers averaged 146 minutes without power. That's below the US figure of 269 and puts the state 44th highest of 51. Major storms caused 57% of that; ordinary days gave 62 minutes. Of the last ten years, 2020 was the worst at 336 minutes; since the ten-year average is 158, 2025 came in 13 minutes under it.
Each year since 2016
| Year | Minutes out, all events | Rank of 51 states | Without major storms |
|---|---|---|---|
| 2025 | 146 | 44th | 62 |
| 2024 | 158 | 40th | 59 |
| 2023 | 210 | 27th | 56 |
| 2022 | 91 | 45th | 59 |
| 2021 | 127 | 40th | 64 |
| 2020 | 336 | 22nd | 57 |
| 2019 | 116 | 45th | 74 |
| 2018 | 144 | 36th | 73 |
| 2017 | 120 | 44th | 73 |
| 2016 | 136 | 42nd | 81 |
Illinois utilities and their 2025 outages
| Utility | Customers | Minutes out | Outages each | Minutes per outage |
|---|---|---|---|---|
| Commonwealth Edison Co | 4,194,773 | 77 | 0.66 | 116 |
| Ameren Illinois Company | 1,251,245 | 287 | 1.19 | 242 |
| MidAmerican Energy Co | 86,395 | 304 | 1.87 | 163 |
| City of Springfield | 69,427 | 71 | 0.79 | 90 |
| City of Naperville | 64,025 | 20 | 0.27 | 74 |
MidAmerican Energy Co customers went 304 minutes without power in 2025, while City of Naperville customers went 20. The 15.1 to one spread means your local utility matters more than the 146 minute figure for the state. Across all utilities, customer weighting gives an average of 0.87 power losses per customer during the year, compared with 1.35 across the US. Across Commonwealth Edison Co lines, outages averaged 116 minutes, which is about 1.9 hours. Running a 22 kW unit at half load during that period used $6.83 of gas.
Major disasters FEMA has declared in Illinois since 2016
Altogether 5 major disasters were declared: 4 floods and 1 severe storm, the most recent in September 2024, and COVID-19 is not counted. Set the pad for the generator above the local flood level, a level the permit office can supply for the lot, given 4 flood declarations.
The most declarations named Cook County (3), Henry County (2), St. Clair County (3), Morgan County (2), Calhoun County (2), Monroe County (2), Fulton County (2) and Hancock County (2).
| Declared | Disaster | FEMA number |
|---|---|---|
| September 2024 | Severe Storms, Tornadoes, Straight-Line Winds, and Floodng | DR-4819 |
| November 2023 | Severe Storms and Flooding | DR-4749 |
| August 2023 | Severe Storms and Flooding | DR-4728 |
| October 2022 | Severe Storm and Flooding | DR-4676 |
| September 2019 | Severe Storms and Flooding | DR-4461 |
Illinois and neighboring states
| State | 22 kW on gas, installed | Wage | Minutes out |
|---|---|---|---|
| Illinois | $12,169 to $18,269 | $44.34 | 146 |
| Iowa | $10,769 to $15,269 | $30.38 | 183 |
| Indiana | $11,169 to $16,069 | $34.05 | 379 |
| Kentucky | $10,669 to $14,969 | $29.52 | 396 |
| Missouri | $11,169 to $16,169 | $34.77 | 466 |
| Wisconsin | $11,269 to $16,369 | $35.49 | 264 |
Each neighboring state installs for less than Illinois does, and Kentucky begins $1,500 lower, at $10,669. Outage times vary more than prices do: Missouri saw 466 minutes in 2025, compared with 146 here.
Data: BLS pay figures (May 2025), EIA propane prices (October 26, 2026), EIA gas prices (March to August 2026), EIA outage records, EIA-861, FEMA. All states.