Wind Turbine Payback in Carroll County, IN
Wind turbine payback in Carroll 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 Carroll County, IN averages 5.97 m/s (13.4 mph). A 10 kW turbine there would make about 19,482 kWh a year, worth $3,320 at IN's 17.04¢/kWh. Against an installed cost of about $100,000, that is a payback of 30 years, and the turbine is built to last about 20.
What to do in Carroll County
A home turbine is not worth buying for savings in Carroll County unless your spot is far windier than the county average, 7.3 m/s at the hub against 5.97 m/s here. Per kW, solar panels would make about 1,159 kWh a year here against the turbine's 1,948, so get a solar quote first.
What would have to change
- Power would have to cost 26¢/kWh, 1.5 times what IN pays now.
- Or the average wind at the hub would have to be 7.3 m/s instead of 5.97. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of IN
Carroll County is the 891st 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 Carroll County
April is the strongest month here, at 6.95 m/s and about 2,195 kWh. August is the weakest, 4.49 m/s and 788 kWh, so the best month makes 2.8 times the worst. November to March brings in 52% of the year's output in Carroll County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.73 m/s | 2,132 kWh | $363 |
| February | 6.63 m/s | 1,871 kWh | $319 |
| March | 6.62 m/s | 2,065 kWh | $352 |
| April | 6.95 m/s | 2,195 kWh | $374 |
| May | 6.01 m/s | 1,680 kWh | $286 |
| June | 5.21 m/s | 1,149 kWh | $196 |
| July | 4.50 m/s | 793 kWh | $135 |
| August | 4.49 m/s | 788 kWh | $134 |
| September | 5.12 m/s | 1,098 kWh | $187 |
| October | 6.22 m/s | 1,815 kWh | $309 |
| November | 6.68 m/s | 2,031 kWh | $346 |
| December | 6.56 m/s | 2,027 kWh | $345 |
What a taller tower would buy
Measured at 10 m the wind in Carroll County averages 4.64 m/s; at 50 m it is 6.72 m/s. That gives a shear exponent of 0.230, typical of ordinary open country. Going from 20 m to 50 m takes output from 15,627 to 25,020 kWh a year, 60% 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 | 5.44 m/s | 15,627 kWh | 38 years |
| 30 m | 5.98 m/s | 19,520 kWh | 30 years |
| 40 m | 6.38 m/s | 22,549 kWh | 26 years |
| 50 m | 6.72 m/s | 25,020 kWh | 24 years |
Counties around Carroll County
None of the 6 closest counties is windier than Carroll County.
- Cass County, IN: 5.94 m/s, 19,260 kWh, payback 31 years (16 mi)
- White County, IN: 5.97 m/s, 19,482 kWh, payback 30 years (19 mi)
- Clinton County, IN: 5.95 m/s, 19,334 kWh, payback 30 years (20 mi)
- Tippecanoe County, IN: 5.97 m/s, 19,482 kWh, payback 30 years (22 mi)
- Howard County, IN: 5.95 m/s, 19,334 kWh, payback 30 years (25 mi)
- Miami County, IN: 5.94 m/s, 19,260 kWh, payback 31 years (30 mi)
Sun versus wind in Carroll County
Carroll County gets 3.97 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,159 kWh a year; one kW of the turbine above makes 1,948. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.7 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.