Wind Turbine Payback in Ripley County, IN
Wind turbine payback in Ripley 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 Ripley County, IN averages 3.91 m/s (8.7 mph). A 10 kW turbine there would make about 6,134 kWh a year, worth $1,045 at IN's 17.04¢/kWh. Against an installed cost of about $100,000, that is a payback of 96 years, and the turbine is built to last about 20.
What to do in Ripley County
A home turbine is not worth buying for savings in Ripley County unless your spot is far windier than the county average, 7.3 m/s at the hub against 3.91 m/s here. Per kW, solar panels would make about 1,165 kWh a year here against the turbine's 613, so get a solar quote first.
What would have to change
- Power would have to cost 82¢/kWh, 4.8 times what IN pays now.
- Or the average wind at the hub would have to be 7.3 m/s instead of 3.91. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of IN
Ripley County is the 2,125th 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 Ripley County
January is the strongest month here, at 4.62 m/s and about 858 kWh. August is the weakest, 2.92 m/s and 201 kWh, so the best month makes 4.3 times the worst. November to March brings in 58% of the year's output in Ripley County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.62 m/s | 858 kWh | $146 |
| February | 4.62 m/s | 775 kWh | $132 |
| March | 4.58 m/s | 832 kWh | $142 |
| April | 4.58 m/s | 809 kWh | $138 |
| May | 3.76 m/s | 461 kWh | $79 |
| June | 3.29 m/s | 291 kWh | $50 |
| July | 2.93 m/s | 203 kWh | $35 |
| August | 2.92 m/s | 201 kWh | $34 |
| September | 3.25 m/s | 279 kWh | $48 |
| October | 3.87 m/s | 503 kWh | $86 |
| November | 4.19 m/s | 621 kWh | $106 |
| December | 4.30 m/s | 696 kWh | $119 |
What a taller tower would buy
Measured at 10 m the wind in Ripley County averages 2.58 m/s; at 50 m it is 4.74 m/s. That gives a shear exponent of 0.378, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 3,766 to 10,826 kWh a year, 187% 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 | 3.35 m/s | 3,766 kWh | over 100 years |
| 30 m | 3.91 m/s | 6,122 kWh | 96 years |
| 40 m | 4.36 m/s | 8,498 kWh | 69 years |
| 50 m | 4.74 m/s | 10,826 kWh | 54 years |
Counties around Ripley County
3 of the 6 closest counties are windier at turbine height; the windiest, Decatur County, averages 5.58 m/s.
- Dearborn County, IN: 3.91 m/s, 6,134 kWh, payback 96 years (16 mi)
- Decatur County, IN: 5.58 m/s, 16,616 kWh, payback 35 years (19 mi)
- Ohio County, IN: 3.91 m/s, 6,134 kWh, payback 96 years (19 mi)
- Jennings County, IN: 4.82 m/s, 11,341 kWh, payback 52 years (21 mi)
- Switzerland County, IN: 3.91 m/s, 6,134 kWh, payback 96 years (23 mi)
- Franklin County, IN: 5.35 m/s, 14,963 kWh, payback 39 years (24 mi)
Sun versus wind in Ripley County
Ripley County gets 3.99 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,165 kWh a year; one kW of the turbine above makes 613. Kilowatt for kilowatt, panels make 1.9 times as much here as the turbine. 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.