Wind Turbine Payback in Grant County, IN
Wind turbine payback in Grant 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 Grant 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 Grant County
A home turbine is not worth buying for savings in Grant 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 1,150 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
Grant 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 Grant County
January is the strongest month here, at 6.86 m/s and about 2,211 kWh. August is the weakest, 4.44 m/s and 762 kWh, so the best month makes 2.9 times the worst. November to March brings in 52% of the year's output in Grant County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.86 m/s | 2,211 kWh | $377 |
| February | 6.71 m/s | 1,912 kWh | $326 |
| March | 6.64 m/s | 2,073 kWh | $353 |
| April | 6.92 m/s | 2,176 kWh | $371 |
| May | 5.96 m/s | 1,649 kWh | $281 |
| June | 5.20 m/s | 1,140 kWh | $194 |
| July | 4.47 m/s | 780 kWh | $133 |
| August | 4.44 m/s | 762 kWh | $130 |
| September | 5.06 m/s | 1,065 kWh | $181 |
| October | 6.21 m/s | 1,805 kWh | $308 |
| November | 6.65 m/s | 2,017 kWh | $344 |
| December | 6.64 m/s | 2,073 kWh | $353 |
What a taller tower would buy
Measured at 10 m the wind in Grant County averages 4.65 m/s; at 50 m it is 6.72 m/s. That gives a shear exponent of 0.229, typical of ordinary open country. Going from 20 m to 50 m takes output from 15,663 to 25,020 kWh a year, 60% 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 | 5.45 m/s | 15,663 kWh | 38 years |
| 30 m | 5.98 m/s | 19,542 kWh | 30 years |
| 40 m | 6.39 m/s | 22,560 kWh | 26 years |
| 50 m | 6.72 m/s | 25,020 kWh | 24 years |
Counties around Grant County
None of the 6 closest counties is windier than Grant County.
- Blackford County, IN: 5.98 m/s, 19,556 kWh, payback 30 years (18 mi)
- Huntington County, IN: 5.95 m/s, 19,334 kWh, payback 30 years (23 mi)
- Wabash County, IN: 5.95 m/s, 19,334 kWh, payback 30 years (24 mi)
- Delaware County, IN: 5.87 m/s, 18,742 kWh, payback 31 years (24 mi)
- Howard County, IN: 5.95 m/s, 19,334 kWh, payback 30 years (24 mi)
- Madison County, IN: 5.87 m/s, 18,742 kWh, payback 31 years (24 mi)
Sun versus wind in Grant County
Grant County gets 3.94 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,150 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 1.7 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.