Wind Turbine Payback in Sibley County, MN
Wind turbine payback in Sibley 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 Sibley County, MN averages 6.27 m/s (14 mph). A 10 kW turbine there would make about 21,706 kWh a year, worth $3,569 at MN's 16.44¢/kWh. Against an installed cost of about $100,000, that is a payback of 28 years, and the turbine is built to last about 20.
What to do in Sibley County
A home turbine is not worth buying for savings in Sibley County unless your spot is far windier than the county average, 7.5 m/s at the hub against 6.27 m/s here. Per kW, solar panels would make about 1,145 kWh a year here against the turbine's 2,171, so get a solar quote first.
What would have to change
- Power would have to cost 23¢/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 6.27. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MN
Sibley County is the 510th 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 Sibley County
April is the strongest month here, at 6.98 m/s and about 2,213 kWh. August is the weakest, 5.20 m/s and 1,181 kWh, so the best month makes 1.9 times the worst. November to March brings in 45% of the year's output in Sibley County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.54 m/s | 2,010 kWh | $330 |
| February | 6.57 m/s | 1,836 kWh | $302 |
| March | 6.66 m/s | 2,088 kWh | $343 |
| April | 6.98 m/s | 2,213 kWh | $364 |
| May | 6.48 m/s | 1,976 kWh | $325 |
| June | 5.85 m/s | 1,531 kWh | $252 |
| July | 5.22 m/s | 1,191 kWh | $196 |
| August | 5.20 m/s | 1,181 kWh | $194 |
| September | 6.26 m/s | 1,776 kWh | $292 |
| October | 6.63 m/s | 2,071 kWh | $340 |
| November | 6.58 m/s | 1,972 kWh | $324 |
| December | 6.36 m/s | 1,898 kWh | $312 |
What a taller tower would buy
Measured at 10 m the wind in Sibley County averages 4.96 m/s; at 50 m it is 7 m/s. That gives a shear exponent of 0.214, typical of ordinary open country. Going from 20 m to 50 m takes output from 17,885 to 27,043 kWh a year, 51% 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 | 5.75 m/s | 17,885 kWh | 34 years |
| 30 m | 6.28 m/s | 21,744 kWh | 28 years |
| 40 m | 6.67 m/s | 24,681 kWh | 25 years |
| 50 m | 7 m/s | 27,043 kWh | 23 years |
Counties around Sibley County
1 of the 6 closest counties is windier at turbine height; the windiest, Brown County, averages 6.53 m/s.
- Nicollet County, MN: 6.27 m/s, 21,706 kWh, payback 28 years (15 mi)
- McLeod County, MN: 6.25 m/s, 21,558 kWh, payback 28 years (17 mi)
- Carver County, MN: 6.05 m/s, 20,075 kWh, payback 30 years (27 mi)
- Le Sueur County, MN: 6.23 m/s, 21,410 kWh, payback 28 years (28 mi)
- Brown County, MN: 6.53 m/s, 23,628 kWh, payback 26 years (34 mi)
- Scott County, MN: 6.23 m/s, 21,410 kWh, payback 28 years (35 mi)
Sun versus wind in Sibley County
Sibley County gets 3.92 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,145 kWh a year; one kW of the turbine above makes 2,171. 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.