Wind Turbine Payback in Dunn County, ND
Wind turbine payback in Dunn 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 Dunn County, ND averages 6.57 m/s (14.7 mph). A 10 kW turbine there would make about 23,922 kWh a year, worth $2,981 at ND's 12.46¢/kWh. Against an installed cost of about $100,000, that is a payback of 34 years, and the turbine is built to last about 20.
What to do in Dunn County
A home turbine is not worth buying for savings in Dunn County unless your spot is far windier than the county average, 9.1 m/s at the hub against 6.57 m/s here. Per kW, solar panels would make about 1,156 kWh a year here against the turbine's 2,392, so get a solar quote first.
What would have to change
- Power would have to cost 21¢/kWh, 1.7 times what ND pays now.
- Or the average wind at the hub would have to be 9.1 m/s instead of 6.57. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of ND
Dunn County is the 130th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in ND is Bowman County at 6.79 m/s, payback 31 years.
Month by month in Dunn County
October is the strongest month here, at 7.07 m/s and about 2,337 kWh. July is the weakest, 5.76 m/s and 1,521 kWh, so the best month makes 1.5 times the worst. November to March brings in 44% of the year's output in Dunn County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.92 m/s | 2,249 kWh | $280 |
| February | 6.37 m/s | 1,723 kWh | $215 |
| March | 6.83 m/s | 2,194 kWh | $273 |
| April | 6.84 m/s | 2,128 kWh | $265 |
| May | 6.64 m/s | 2,076 kWh | $259 |
| June | 6.20 m/s | 1,741 kWh | $217 |
| July | 5.76 m/s | 1,521 kWh | $190 |
| August | 5.87 m/s | 1,589 kWh | $198 |
| September | 6.50 m/s | 1,922 kWh | $239 |
| October | 7.07 m/s | 2,337 kWh | $291 |
| November | 7.00 m/s | 2,224 kWh | $277 |
| December | 6.81 m/s | 2,183 kWh | $272 |
What a taller tower would buy
Measured at 10 m the wind in Dunn County averages 5.27 m/s; at 50 m it is 7.28 m/s. That gives a shear exponent of 0.201, typical of ordinary open country. Going from 20 m to 50 m takes output from 20,115 to 29,020 kWh a year, 44% 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 | 6.06 m/s | 20,115 kWh | 40 years |
| 30 m | 6.57 m/s | 23,919 kWh | 34 years |
| 40 m | 6.96 m/s | 26,761 kWh | 30 years |
| 50 m | 7.28 m/s | 29,020 kWh | 28 years |
Counties around Dunn County
3 of the 6 closest counties are windier at turbine height; the windiest, Billings County, averages 6.76 m/s.
- Mercer County, ND: 6.52 m/s, 23,554 kWh, payback 34 years (37 mi)
- Stark County, ND: 6.7 m/s, 24,874 kWh, payback 32 years (37 mi)
- Billings County, ND: 6.76 m/s, 25,311 kWh, payback 32 years (43 mi)
- McKenzie County, ND: 6.59 m/s, 24,069 kWh, payback 33 years (46 mi)
- McLean County, ND: 6.52 m/s, 23,554 kWh, payback 34 years (59 mi)
- Mountrail County, ND: 6.53 m/s, 23,628 kWh, payback 34 years (60 mi)
Sun versus wind in Dunn County
Dunn County gets 3.96 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,156 kWh a year; one kW of the turbine above makes 2,392. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 2.1 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.