Wind Turbine Payback in Daviess County, IN
Wind turbine payback in Daviess 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 Daviess County, IN averages 4.61 m/s (10.3 mph). A 10 kW turbine there would make about 10,008 kWh a year, worth $1,705 at IN's 17.04¢/kWh. Against an installed cost of about $100,000, that is a payback of 59 years, and the turbine is built to last about 20.
What to do in Daviess County
A home turbine is not worth buying for savings in Daviess County unless your spot is far windier than the county average, 7.3 m/s at the hub against 4.61 m/s here. Per kW, solar panels would make about 1,206 kWh a year here against the turbine's 1,001, so get a solar quote first.
What would have to change
- Power would have to cost 50¢/kWh, 2.9 times what IN pays now.
- Or the average wind at the hub would have to be 7.3 m/s instead of 4.61. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of IN
Daviess County is the 1,685th 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 Daviess County
March is the strongest month here, at 5.38 m/s and about 1,287 kWh. July is the weakest, 3.41 m/s and 339 kWh, so the best month makes 3.8 times the worst. November to March brings in 56% of the year's output in Daviess County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.33 m/s | 1,256 kWh | $214 |
| February | 5.33 m/s | 1,135 kWh | $193 |
| March | 5.38 m/s | 1,287 kWh | $219 |
| April | 5.45 m/s | 1,286 kWh | $219 |
| May | 4.55 m/s | 818 kWh | $139 |
| June | 3.90 m/s | 500 kWh | $85 |
| July | 3.41 m/s | 339 kWh | $58 |
| August | 3.42 m/s | 342 kWh | $58 |
| September | 3.88 m/s | 490 kWh | $83 |
| October | 4.65 m/s | 872 kWh | $149 |
| November | 5.03 m/s | 1,045 kWh | $178 |
| December | 5.06 m/s | 1,100 kWh | $187 |
What a taller tower would buy
Measured at 10 m the wind in Daviess County averages 3.28 m/s; at 50 m it is 5.4 m/s. That gives a shear exponent of 0.310, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 6,907 to 15,319 kWh a year, 122% 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 | 4.06 m/s | 6,907 kWh | 85 years |
| 30 m | 4.61 m/s | 10,003 kWh | 59 years |
| 40 m | 5.04 m/s | 12,799 kWh | 46 years |
| 50 m | 5.4 m/s | 15,319 kWh | 38 years |
Counties around Daviess County
4 of the 6 closest counties are windier at turbine height; the windiest, Sullivan County, averages 5.61 m/s.
- Martin County, IN: 4.61 m/s, 10,008 kWh, payback 59 years (15 mi)
- Knox County, IN: 5.53 m/s, 16,254 kWh, payback 36 years (19 mi)
- Pike County, IN: 5.53 m/s, 16,254 kWh, payback 36 years (22 mi)
- Greene County, IN: 4.68 m/s, 10,445 kWh, payback 56 years (25 mi)
- Dubois County, IN: 4.61 m/s, 10,008 kWh, payback 59 years (25 mi)
- Sullivan County, IN: 5.61 m/s, 16,834 kWh, payback 35 years (33 mi)
Sun versus wind in Daviess County
Daviess 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 1,001. Kilowatt for kilowatt, panels make 1.2 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.