Wind Turbine Payback in Grant County, MN
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, MN averages 6.37 m/s (14.2 mph). A 10 kW turbine there would make about 22,447 kWh a year, worth $3,690 at MN's 16.44¢/kWh. Against an installed cost of about $100,000, that is a payback of 27 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, 7.5 m/s at the hub against 6.37 m/s here. Per kW, solar panels would make about 1,162 kWh a year here against the turbine's 2,245, so get a solar quote first.
What would have to change
- Power would have to cost 22¢/kWh, 1.4 times what MN pays now.
- Or the average wind at the hub would have to be 7.5 m/s instead of 6.37. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MN
Grant County is the 380th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in MN is Lincoln County at 6.68 m/s, payback 25 years.
Month by month in Grant County
April is the strongest month here, at 7.03 m/s and about 2,242 kWh. July is the weakest, 5.51 m/s and 1,366 kWh, so the best month makes 1.6 times the worst. November to March brings in 42% of the year's output in Grant County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.31 m/s | 1,872 kWh | $308 |
| February | 6.38 m/s | 1,726 kWh | $284 |
| March | 6.63 m/s | 2,069 kWh | $340 |
| April | 7.03 m/s | 2,242 kWh | $369 |
| May | 6.80 m/s | 2,174 kWh | $357 |
| June | 6.11 m/s | 1,686 kWh | $277 |
| July | 5.51 m/s | 1,366 kWh | $225 |
| August | 5.59 m/s | 1,416 kWh | $233 |
| September | 6.50 m/s | 1,926 kWh | $317 |
| October | 6.82 m/s | 2,185 kWh | $359 |
| November | 6.54 m/s | 1,948 kWh | $320 |
| December | 6.23 m/s | 1,821 kWh | $299 |
What a taller tower would buy
Measured at 10 m the wind in Grant County averages 5.06 m/s; at 50 m it is 7.09 m/s. That gives a shear exponent of 0.210, typical of ordinary open country. Going from 20 m to 50 m takes output from 18,587 to 27,684 kWh a year, 49% 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 | 5.85 m/s | 18,587 kWh | 33 years |
| 30 m | 6.37 m/s | 22,438 kWh | 27 years |
| 40 m | 6.77 m/s | 25,351 kWh | 24 years |
| 50 m | 7.09 m/s | 27,684 kWh | 22 years |
Counties around Grant County
4 of the 6 closest counties are windier at turbine height; the windiest, Otter Tail County, averages 6.59 m/s.
- Stevens County, MN: 6.34 m/s, 22,225 kWh, payback 27 years (23 mi)
- Traverse County, MN: 6.37 m/s, 22,447 kWh, payback 27 years (25 mi)
- Douglas County, MN: 6.52 m/s, 23,554 kWh, payback 26 years (26 mi)
- Otter Tail County, MN: 6.59 m/s, 24,069 kWh, payback 25 years (36 mi)
- Pope County, MN: 6.39 m/s, 22,595 kWh, payback 27 years (36 mi)
- Wilkin County, MN: 6.45 m/s, 23,038 kWh, payback 26 years (37 mi)
Sun versus wind in Grant County
Grant County gets 3.98 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,162 kWh a year; one kW of the turbine above makes 2,245. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.9 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.