Wind Turbine Payback in Union County, IN
Wind turbine payback in Union 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 Union County, IN averages 5.35 m/s (12 mph). A 10 kW turbine there would make about 14,963 kWh a year, worth $2,550 at IN's 17.04¢/kWh. Against an installed cost of about $100,000, that is a payback of 39 years, and the turbine is built to last about 20.
What to do in Union County
A home turbine is not worth buying for savings in Union County unless your spot is far windier than the county average, 7.3 m/s at the hub against 5.35 m/s here. Per kW, solar panels would make about 1,165 kWh a year here against the turbine's 1,496, so get a solar quote first.
What would have to change
- Power would have to cost 33¢/kWh, 2.0 times what IN pays now.
- Or the average wind at the hub would have to be 7.3 m/s instead of 5.35. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of IN
Union County is the 1,303rd 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 Union County
January is the strongest month here, at 6.26 m/s and about 1,837 kWh. August is the weakest, 3.99 m/s and 555 kWh, so the best month makes 3.3 times the worst. November to March brings in 54% of the year's output in Union County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.26 m/s | 1,837 kWh | $313 |
| February | 6.17 m/s | 1,609 kWh | $274 |
| March | 6.13 m/s | 1,754 kWh | $299 |
| April | 6.26 m/s | 1,778 kWh | $303 |
| May | 5.24 m/s | 1,205 kWh | $205 |
| June | 4.60 m/s | 817 kWh | $139 |
| July | 4.03 m/s | 570 kWh | $97 |
| August | 3.99 m/s | 555 kWh | $95 |
| September | 4.48 m/s | 760 kWh | $130 |
| October | 5.45 m/s | 1,332 kWh | $227 |
| November | 5.84 m/s | 1,521 kWh | $259 |
| December | 5.92 m/s | 1,621 kWh | $276 |
What a taller tower would buy
Measured at 10 m the wind in Union County averages 4.06 m/s; at 50 m it is 6.09 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 11,435 to 20,371 kWh a year, 78% 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 | 4.83 m/s | 11,435 kWh | 51 years |
| 30 m | 5.35 m/s | 14,994 kWh | 39 years |
| 40 m | 5.76 m/s | 17,910 kWh | 33 years |
| 50 m | 6.09 m/s | 20,371 kWh | 29 years |
Counties around Union County
2 of the 6 closest counties are windier at turbine height; the windiest, Wayne County, averages 5.92 m/s.
- Fayette County, IN: 5.35 m/s, 14,963 kWh, payback 39 years (14 mi)
- Franklin County, IN: 5.35 m/s, 14,963 kWh, payback 39 years (17 mi)
- Preble County, OH: 5.33 m/s, 14,821 kWh, payback 36 years (17 mi)
- Wayne County, IN: 5.92 m/s, 19,112 kWh, payback 31 years (17 mi)
- Butler County, OH: 5.33 m/s, 14,821 kWh, payback 36 years (23 mi)
- Rush County, IN: 5.58 m/s, 16,616 kWh, payback 35 years (29 mi)
Sun versus wind in Union County
Union 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 1,496. 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.