Wind Turbine Payback in Otter Tail County, MN
Wind turbine payback in Otter Tail 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 Otter Tail County, MN averages 6.59 m/s (14.7 mph). A 10 kW turbine there would make about 24,069 kWh a year, worth $3,957 at MN's 16.44¢/kWh. Against an installed cost of about $100,000, that is a payback of 25 years, and the turbine is built to last about 20.
What to do in Otter Tail County
A home turbine is not worth buying for savings in Otter Tail County unless your spot is far windier than the county average, 7.5 m/s at the hub against 6.59 m/s here. Per kW, solar panels would make about 1,101 kWh a year here against the turbine's 2,407, so get a solar quote first.
What would have to change
- Power would have to cost 21¢/kWh, 1.3 times what MN pays now.
- Or the average wind at the hub would have to be 7.5 m/s instead of 6.59. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MN
Otter Tail County is the 119th 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 Otter Tail County
April is the strongest month here, at 7.19 m/s and about 2,331 kWh. July is the weakest, 5.65 m/s and 1,454 kWh, so the best month makes 1.6 times the worst. November to March brings in 43% of the year's output in Otter Tail County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.76 m/s | 2,150 kWh | $353 |
| February | 6.79 m/s | 1,957 kWh | $322 |
| March | 6.83 m/s | 2,195 kWh | $361 |
| April | 7.19 m/s | 2,331 kWh | $383 |
| May | 6.87 m/s | 2,217 kWh | $364 |
| June | 6.25 m/s | 1,769 kWh | $291 |
| July | 5.65 m/s | 1,454 kWh | $239 |
| August | 5.77 m/s | 1,527 kWh | $251 |
| September | 6.66 m/s | 2,021 kWh | $332 |
| October | 6.99 m/s | 2,289 kWh | $376 |
| November | 6.78 m/s | 2,091 kWh | $344 |
| December | 6.53 m/s | 2,004 kWh | $329 |
What a taller tower would buy
Measured at 10 m the wind in Otter Tail County averages 5.3 m/s; at 50 m it is 7.29 m/s. That gives a shear exponent of 0.198, typical of ordinary open country. Going from 20 m to 50 m takes output from 20,300 to 29,090 kWh a year, 43% 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 | 6.08 m/s | 20,300 kWh | 30 years |
| 30 m | 6.59 m/s | 24,060 kWh | 25 years |
| 40 m | 6.97 m/s | 26,863 kWh | 23 years |
| 50 m | 7.29 m/s | 29,090 kWh | 21 years |
Counties around Otter Tail County
1 of the 6 closest counties is windier at turbine height; the windiest, Becker County, averages 6.62 m/s.
- Douglas County, MN: 6.52 m/s, 23,554 kWh, payback 26 years (35 mi)
- Grant County, MN: 6.37 m/s, 22,447 kWh, payback 27 years (36 mi)
- Wilkin County, MN: 6.45 m/s, 23,038 kWh, payback 26 years (36 mi)
- Wadena County, MN: 6.45 m/s, 23,038 kWh, payback 26 years (37 mi)
- Becker County, MN: 6.62 m/s, 24,289 kWh, payback 25 years (37 mi)
- Todd County, MN: 6.45 m/s, 23,038 kWh, payback 26 years (45 mi)
Sun versus wind in Otter Tail County
Otter Tail County gets 3.77 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,101 kWh a year; one kW of the turbine above makes 2,407. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 2.2 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.