Wind Turbine Payback in Cass County, MN
Wind turbine payback in Cass 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 Cass County, MN averages 6.38 m/s (14.3 mph). A 10 kW turbine there would make about 22,521 kWh a year, worth $3,702 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 Cass County
A home turbine is not worth buying for savings in Cass County unless your spot is far windier than the county average, 7.5 m/s at the hub against 6.38 m/s here. Per kW, solar panels would make about 1,101 kWh a year here against the turbine's 2,252, 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 6.38. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MN
Cass County is the 359th 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 Cass County
April is the strongest month here, at 6.89 m/s and about 2,158 kWh. July is the weakest, 5.61 m/s and 1,430 kWh, so the best month makes 1.5 times the worst. November to March brings in 43% of the year's output in Cass County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.54 m/s | 2,013 kWh | $331 |
| February | 6.63 m/s | 1,869 kWh | $307 |
| March | 6.59 m/s | 2,046 kWh | $336 |
| April | 6.89 m/s | 2,158 kWh | $355 |
| May | 6.49 m/s | 1,979 kWh | $325 |
| June | 6.07 m/s | 1,662 kWh | $273 |
| July | 5.61 m/s | 1,430 kWh | $235 |
| August | 5.73 m/s | 1,503 kWh | $247 |
| September | 6.50 m/s | 1,926 kWh | $317 |
| October | 6.71 m/s | 2,119 kWh | $348 |
| November | 6.54 m/s | 1,948 kWh | $320 |
| December | 6.26 m/s | 1,837 kWh | $302 |
What a taller tower would buy
Measured at 10 m the wind in Cass County averages 5.11 m/s; at 50 m it is 7.07 m/s. That gives a shear exponent of 0.202, typical of ordinary open country. Going from 20 m to 50 m takes output from 18,782 to 27,542 kWh a year, 47% 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 | 5.88 m/s | 18,782 kWh | 32 years |
| 30 m | 6.38 m/s | 22,498 kWh | 27 years |
| 40 m | 6.76 m/s | 25,300 kWh | 24 years |
| 50 m | 7.07 m/s | 27,542 kWh | 22 years |
Counties around Cass County
3 of the 6 closest counties are windier at turbine height; the windiest, Hubbard County, averages 6.51 m/s.
- Hubbard County, MN: 6.51 m/s, 23,481 kWh, payback 26 years (29 mi)
- Crow Wing County, MN: 6.41 m/s, 22,743 kWh, payback 27 years (34 mi)
- Wadena County, MN: 6.45 m/s, 23,038 kWh, payback 26 years (40 mi)
- Aitkin County, MN: 6.32 m/s, 22,077 kWh, payback 28 years (50 mi)
- Itasca County, MN: 5.88 m/s, 18,816 kWh, payback 32 years (50 mi)
- Morrison County, MN: 6.34 m/s, 22,225 kWh, payback 27 years (64 mi)
Sun versus wind in Cass County
Cass 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 2,252. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 2.0 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.