Wind Turbine Payback in Bartholomew County, IN
Wind turbine payback in Bartholomew 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 Bartholomew County, IN averages 4.82 m/s (10.8 mph). A 10 kW turbine there would make about 11,341 kWh a year, worth $1,933 at IN's 17.04¢/kWh. Against an installed cost of about $100,000, that is a payback of 52 years, and the turbine is built to last about 20.
What to do in Bartholomew County
A home turbine is not worth buying for savings in Bartholomew County unless your spot is far windier than the county average, 7.3 m/s at the hub against 4.82 m/s here. Per kW, solar panels would make about 1,165 kWh a year here against the turbine's 1,134, so get a solar quote first.
What would have to change
- Power would have to cost 44¢/kWh, 2.6 times what IN pays now.
- Or the average wind at the hub would have to be 7.3 m/s instead of 4.82. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of IN
Bartholomew County is the 1,546th 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 Bartholomew County
January is the strongest month here, at 5.61 m/s and about 1,430 kWh. July is the weakest, 3.58 m/s and 394 kWh, so the best month makes 3.6 times the worst. November to March brings in 55% of the year's output in Bartholomew County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.61 m/s | 1,430 kWh | $244 |
| February | 5.58 m/s | 1,277 kWh | $218 |
| March | 5.59 m/s | 1,419 kWh | $242 |
| April | 5.68 m/s | 1,426 kWh | $243 |
| May | 4.69 m/s | 894 kWh | $152 |
| June | 4.09 m/s | 577 kWh | $98 |
| July | 3.58 m/s | 394 kWh | $67 |
| August | 3.58 m/s | 397 kWh | $68 |
| September | 4.07 m/s | 570 kWh | $97 |
| October | 4.87 m/s | 994 kWh | $169 |
| November | 5.25 m/s | 1,170 kWh | $199 |
| December | 5.32 m/s | 1,250 kWh | $213 |
What a taller tower would buy
Measured at 10 m the wind in Bartholomew County averages 3.54 m/s; at 50 m it is 5.57 m/s. That gives a shear exponent of 0.282, typical of ordinary open country. Going from 20 m to 50 m takes output from 8,186 to 16,544 kWh a year, 102% 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 | 4.3 m/s | 8,186 kWh | 72 years |
| 30 m | 4.82 m/s | 11,359 kWh | 52 years |
| 40 m | 5.23 m/s | 14,118 kWh | 42 years |
| 50 m | 5.57 m/s | 16,544 kWh | 36 years |
Counties around Bartholomew County
3 of the 6 closest counties are windier at turbine height; the windiest, Decatur County, averages 5.58 m/s.
- Brown County, IN: 4.32 m/s, 8,289 kWh, payback 71 years (18 mi)
- Jennings County, IN: 4.82 m/s, 11,341 kWh, payback 52 years (20 mi)
- Jackson County, IN: 4.32 m/s, 8,289 kWh, payback 71 years (22 mi)
- Decatur County, IN: 5.58 m/s, 16,616 kWh, payback 35 years (22 mi)
- Johnson County, IN: 5.09 m/s, 13,146 kWh, payback 45 years (23 mi)
- Shelby County, IN: 5.58 m/s, 16,616 kWh, payback 35 years (23 mi)
Sun versus wind in Bartholomew County
Bartholomew 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 1,134. Kilowatt for kilowatt, panels make 1.0 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.