Wind Turbine Payback in White County, IL
Wind turbine payback in White County
No. The turbine wears out before it pays for itself.
At 30 m, the height a home turbine tower usually reaches, the wind in White County, IL averages 5.53 m/s (12.4 mph). A 10 kW turbine there would make about 16,254 kWh a year, worth $3,126 at IL's 19.23¢/kWh. Against an installed cost of about $100,000, that is a payback of 32 years, and the turbine is built to last about 20.
What to do in White County
A home turbine is not worth buying for savings in White County unless your spot is far windier than the county average, 6.8 m/s at the hub against 5.53 m/s here. Per kW, solar panels would make about 1,215 kWh a year here against the turbine's 1,625, so get a solar quote first.
What would have to change
- Power would have to cost 31¢/kWh, 1.6 times what IL pays now.
- Or the average wind at the hub would have to be 6.8 m/s instead of 5.53. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of IL
White County is the 1,195th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in IL is Cook County at 6.73 m/s, payback 21 years.
Month by month in White County
April is the strongest month here, at 6.57 m/s and about 1,967 kWh. July is the weakest, 4.10 m/s and 602 kWh, so the best month makes 3.3 times the worst. November to March brings in 53% of the year's output in White County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.28 m/s | 1,850 kWh | $356 |
| February | 6.25 m/s | 1,651 kWh | $317 |
| March | 6.43 m/s | 1,944 kWh | $374 |
| April | 6.57 m/s | 1,967 kWh | $378 |
| May | 5.53 m/s | 1,382 kWh | $266 |
| June | 4.68 m/s | 858 kWh | $165 |
| July | 4.10 m/s | 602 kWh | $116 |
| August | 4.12 m/s | 610 kWh | $117 |
| September | 4.61 m/s | 822 kWh | $158 |
| October | 5.67 m/s | 1,469 kWh | $282 |
| November | 6.10 m/s | 1,683 kWh | $324 |
| December | 6.05 m/s | 1,706 kWh | $328 |
What a taller tower would buy
Measured at 10 m the wind in White County averages 4.2 m/s; at 50 m it is 6.29 m/s. That gives a shear exponent of 0.251, typical of ordinary open country. Going from 20 m to 50 m takes output from 12,519 to 21,855 kWh a year, 75% more, before counting the extra cost of the taller tower. Why tower height decides it explains the shear behind these numbers.
| Hub height | Average wind | Output | Payback |
|---|---|---|---|
| 20 m | 5 m/s | 12,519 kWh | 42 years |
| 30 m | 5.53 m/s | 16,276 kWh | 32 years |
| 40 m | 5.95 m/s | 19,314 kWh | 27 years |
| 50 m | 6.29 m/s | 21,855 kWh | 24 years |
Counties around White County
2 of the 6 closest counties are windier at turbine height; the windiest, Edwards County, averages 5.61 m/s.
- Posey County, IN: 5.53 m/s, 16,254 kWh, payback 36 years (17 mi)
- Hamilton County, IL: 5.51 m/s, 16,109 kWh, payback 32 years (20 mi)
- Gallatin County, IL: 5.53 m/s, 16,254 kWh, payback 32 years (22 mi)
- Edwards County, IL: 5.61 m/s, 16,834 kWh, payback 31 years (24 mi)
- Wayne County, IL: 5.61 m/s, 16,834 kWh, payback 31 years (28 mi)
- Saline County, IL: 5.51 m/s, 16,109 kWh, payback 32 years (31 mi)
Sun versus wind in White County
White County gets 4.16 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,215 kWh a year; one kW of the turbine above makes 1,625. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.3 times. Panel output assumes an 80% system performance ratio. Wind or solar runs the same comparison for every county.
How this is worked out
Wind is NASA's Power climate record, the 2001-2025 average at 10 m and 50 m for the county's centre, carried to 30 m with this county's own measured wind shear and spread into hours with a Rayleigh distribution. The turbine is a generic 10 kW, 7 m rotor machine with 10% losses. Cost is $10,000 per kW installed with no tax credit, because the federal one ended in 2025. One county-centre number cannot see your hilltop or your tree line, so treat it as the starting point for a site survey, not a substitute. The full method and its weak spots are in how the numbers are made.