Wind Turbine Payback in Vanderburgh County, IN
Wind turbine payback in Vanderburgh 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 Vanderburgh County, IN averages 5.42 m/s (12.1 mph). A 10 kW turbine there would make about 15,462 kWh a year, worth $2,635 at IN's 17.04¢/kWh. Against an installed cost of about $100,000, that is a payback of 38 years, and the turbine is built to last about 20.
What to do in Vanderburgh County
A home turbine is not worth buying for savings in Vanderburgh County unless your spot is far windier than the county average, 7.3 m/s at the hub against 5.42 m/s here. Per kW, solar panels would make about 1,206 kWh a year here against the turbine's 1,546, so get a solar quote first.
What would have to change
- Power would have to cost 32¢/kWh, 1.9 times what IN pays now.
- Or the average wind at the hub would have to be 7.3 m/s instead of 5.42. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of IN
Vanderburgh County is the 1,264th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in IN is Lake County at 6.17 m/s, payback 28 years.
Month by month in Vanderburgh County
April is the strongest month here, at 6.45 m/s and about 1,896 kWh. July is the weakest, 3.98 m/s and 551 kWh, so the best month makes 3.4 times the worst. November to March brings in 54% of the year's output in Vanderburgh County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.22 m/s | 1,810 kWh | $308 |
| February | 6.18 m/s | 1,614 kWh | $275 |
| March | 6.32 m/s | 1,876 kWh | $320 |
| April | 6.45 m/s | 1,896 kWh | $323 |
| May | 5.42 m/s | 1,316 kWh | $224 |
| June | 4.57 m/s | 803 kWh | $137 |
| July | 3.98 m/s | 551 kWh | $94 |
| August | 3.99 m/s | 555 kWh | $95 |
| September | 4.50 m/s | 768 kWh | $131 |
| October | 5.53 m/s | 1,381 kWh | $235 |
| November | 5.98 m/s | 1,607 kWh | $274 |
| December | 5.97 m/s | 1,655 kWh | $282 |
What a taller tower would buy
Measured at 10 m the wind in Vanderburgh County averages 4.11 m/s; at 50 m it is 6.17 m/s. That gives a shear exponent of 0.252, typical of ordinary open country. Going from 20 m to 50 m takes output from 11,852 to 20,965 kWh a year, 77% 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 | 4.9 m/s | 11,852 kWh | 50 years |
| 30 m | 5.42 m/s | 15,496 kWh | 38 years |
| 40 m | 5.83 m/s | 18,467 kWh | 32 years |
| 50 m | 6.17 m/s | 20,965 kWh | 28 years |
Counties around Vanderburgh County
2 of the 6 closest counties are windier at turbine height; the windiest, Posey County, averages 5.53 m/s.
- Posey County, IN: 5.53 m/s, 16,254 kWh, payback 36 years (15 mi)
- Henderson County, KY: 5.42 m/s, 15,462 kWh, payback 46 years (16 mi)
- Warrick County, IN: 5.42 m/s, 15,462 kWh, payback 38 years (18 mi)
- Gibson County, IN: 5.53 m/s, 16,254 kWh, payback 36 years (21 mi)
- Spencer County, IN: 4.53 m/s, 9,519 kWh, payback 62 years (31 mi)
- Union County, KY: 5.26 m/s, 14,327 kWh, payback 49 years (32 mi)
Sun versus wind in Vanderburgh County
Vanderburgh County gets 4.13 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,206 kWh a year; one kW of the turbine above makes 1,546. 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.