Wind Turbine Payback in DeKalb County, IN
Wind turbine payback in DeKalb 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 DeKalb County, IN averages 5.98 m/s (13.4 mph). A 10 kW turbine there would make about 19,556 kWh a year, worth $3,332 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 DeKalb County
A home turbine is not worth buying for savings in DeKalb County unless your spot is far windier than the county average, 7.3 m/s at the hub against 5.98 m/s here. Per kW, solar panels would make about 1,115 kWh a year here against the turbine's 1,956, 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 5.98. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of IN
DeKalb County is the 873rd 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 DeKalb County
January is the strongest month here, at 6.83 m/s and about 2,192 kWh. August is the weakest, 4.56 m/s and 826 kWh, so the best month makes 2.7 times the worst. November to March brings in 52% of the year's output in DeKalb County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.83 m/s | 2,192 kWh | $374 |
| February | 6.74 m/s | 1,930 kWh | $329 |
| March | 6.60 m/s | 2,048 kWh | $349 |
| April | 6.88 m/s | 2,153 kWh | $367 |
| May | 5.92 m/s | 1,623 kWh | $277 |
| June | 5.17 m/s | 1,126 kWh | $192 |
| July | 4.62 m/s | 854 kWh | $146 |
| August | 4.56 m/s | 826 kWh | $141 |
| September | 5.16 m/s | 1,121 kWh | $191 |
| October | 6.26 m/s | 1,836 kWh | $313 |
| November | 6.57 m/s | 1,966 kWh | $335 |
| December | 6.58 m/s | 2,037 kWh | $347 |
What a taller tower would buy
Measured at 10 m the wind in DeKalb County averages 4.67 m/s; at 50 m it is 6.71 m/s. That gives a shear exponent of 0.225, typical of ordinary open country. Going from 20 m to 50 m takes output from 15,748 to 24,947 kWh a year, 58% 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 | 5.46 m/s | 15,748 kWh | 37 years |
| 30 m | 5.98 m/s | 19,567 kWh | 30 years |
| 40 m | 6.38 m/s | 22,532 kWh | 26 years |
| 50 m | 6.71 m/s | 24,947 kWh | 24 years |
Counties around DeKalb County
2 of the 6 closest counties are windier at turbine height; the windiest, Noble County, averages 5.99 m/s.
- Steuben County, IN: 5.98 m/s, 19,556 kWh, payback 30 years (17 mi)
- Allen County, IN: 5.9 m/s, 18,964 kWh, payback 31 years (21 mi)
- Noble County, IN: 5.99 m/s, 19,630 kWh, payback 30 years (21 mi)
- Williams County, OH: 5.92 m/s, 19,112 kWh, payback 28 years (25 mi)
- Defiance County, OH: 5.92 m/s, 19,112 kWh, payback 28 years (27 mi)
- LaGrange County, IN: 5.99 m/s, 19,630 kWh, payback 30 years (28 mi)
Sun versus wind in DeKalb County
DeKalb County gets 3.82 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,115 kWh a year; one kW of the turbine above makes 1,956. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.8 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.