Wind Turbine Payback in Marshall County, MN
Wind turbine payback in Marshall 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 Marshall County, MN averages 6.31 m/s (14.1 mph). A 10 kW turbine there would make about 22,003 kWh a year, worth $3,617 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 Marshall County
A home turbine is not worth buying for savings in Marshall County unless your spot is far windier than the county average, 7.5 m/s at the hub against 6.31 m/s here. Per kW, solar panels would make about 1,101 kWh a year here against the turbine's 2,200, 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 6.31. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MN
Marshall County is the 460th 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 Marshall County
October is the strongest month here, at 6.67 m/s and about 2,097 kWh. July is the weakest, 5.62 m/s and 1,438 kWh, so the best month makes 1.5 times the worst. November to March brings in 43% of the year's output in Marshall County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.40 m/s | 1,928 kWh | $317 |
| February | 6.36 m/s | 1,716 kWh | $282 |
| March | 6.56 m/s | 2,024 kWh | $333 |
| April | 6.74 m/s | 2,067 kWh | $340 |
| May | 6.58 m/s | 2,035 kWh | $335 |
| June | 6.05 m/s | 1,647 kWh | $271 |
| July | 5.62 m/s | 1,438 kWh | $236 |
| August | 5.71 m/s | 1,494 kWh | $246 |
| September | 6.41 m/s | 1,872 kWh | $308 |
| October | 6.67 m/s | 2,097 kWh | $345 |
| November | 6.51 m/s | 1,931 kWh | $317 |
| December | 6.16 m/s | 1,776 kWh | $292 |
What a taller tower would buy
Measured at 10 m the wind in Marshall County averages 5.01 m/s; at 50 m it is 7.03 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 18,222 to 27,257 kWh a year, 50% 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 | 5.8 m/s | 18,222 kWh | 33 years |
| 30 m | 6.31 m/s | 22,039 kWh | 28 years |
| 40 m | 6.71 m/s | 24,934 kWh | 24 years |
| 50 m | 7.03 m/s | 27,257 kWh | 22 years |
Counties around Marshall County
4 of the 6 closest counties are windier at turbine height; the windiest, Grand Forks County, averages 6.4 m/s.
- Pennington County, MN: 6.34 m/s, 22,225 kWh, payback 27 years (25 mi)
- Kittson County, MN: 6.25 m/s, 21,558 kWh, payback 28 years (34 mi)
- Red Lake County, MN: 6.34 m/s, 22,225 kWh, payback 27 years (37 mi)
- Roseau County, MN: 5.74 m/s, 17,785 kWh, payback 34 years (37 mi)
- Polk County, MN: 6.34 m/s, 22,225 kWh, payback 27 years (41 mi)
- Grand Forks County, ND: 6.4 m/s, 22,669 kWh, payback 35 years (59 mi)
Sun versus wind in Marshall County
Marshall 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 2,200. 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.