Wind Turbine Payback in Williams County, ND
Wind turbine payback in Williams 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 Williams County, ND averages 6.33 m/s (14.2 mph). A 10 kW turbine there would make about 22,151 kWh a year, worth $2,760 at ND's 12.46¢/kWh. Against an installed cost of about $100,000, that is a payback of 36 years, and the turbine is built to last about 20.
What to do in Williams County
A home turbine is not worth buying for savings in Williams County unless your spot is far windier than the county average, 9.1 m/s at the hub against 6.33 m/s here. Per kW, solar panels would make about 1,148 kWh a year here against the turbine's 2,215, so get a solar quote first.
What would have to change
- Power would have to cost 23¢/kWh, 1.8 times what ND pays now.
- Or the average wind at the hub would have to be 9.1 m/s instead of 6.33. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of ND
Williams County is the 441st 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 Williams County
October is the strongest month here, at 6.70 m/s and about 2,110 kWh. July is the weakest, 5.69 m/s and 1,479 kWh, so the best month makes 1.4 times the worst. November to March brings in 43% of the year's output in Williams County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.50 m/s | 1,987 kWh | $248 |
| February | 6.07 m/s | 1,549 kWh | $193 |
| March | 6.57 m/s | 2,032 kWh | $253 |
| April | 6.75 m/s | 2,074 kWh | $258 |
| May | 6.53 m/s | 2,009 kWh | $250 |
| June | 6.09 m/s | 1,676 kWh | $209 |
| July | 5.69 m/s | 1,479 kWh | $184 |
| August | 5.74 m/s | 1,512 kWh | $188 |
| September | 6.21 m/s | 1,748 kWh | $218 |
| October | 6.70 m/s | 2,110 kWh | $263 |
| November | 6.65 m/s | 2,015 kWh | $251 |
| December | 6.44 m/s | 1,953 kWh | $243 |
What a taller tower would buy
Measured at 10 m the wind in Williams County averages 5.03 m/s; at 50 m it is 7.04 m/s. That gives a shear exponent of 0.209, typical of ordinary open country. Going from 20 m to 50 m takes output from 18,322 to 27,328 kWh a year, 49% 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 | 5.81 m/s | 18,322 kWh | 44 years |
| 30 m | 6.33 m/s | 22,130 kWh | 36 years |
| 40 m | 6.72 m/s | 25,014 kWh | 32 years |
| 50 m | 7.04 m/s | 27,328 kWh | 29 years |
Counties around Williams County
4 of the 6 closest counties are windier at turbine height; the windiest, McKenzie County, averages 6.59 m/s.
- Divide County, ND: 6.42 m/s, 22,817 kWh, payback 35 years (32 mi)
- McKenzie County, ND: 6.59 m/s, 24,069 kWh, payback 33 years (43 mi)
- Sheridan County, MT: 6.24 m/s, 21,484 kWh, payback 33 years (53 mi)
- Mountrail County, ND: 6.53 m/s, 23,628 kWh, payback 34 years (53 mi)
- Burke County, ND: 6.41 m/s, 22,743 kWh, payback 35 years (54 mi)
- Richland County, MT: 6.27 m/s, 21,706 kWh, payback 33 years (63 mi)
Sun versus wind in Williams County
Williams County gets 3.93 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,148 kWh a year; one kW of the turbine above makes 2,215. 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.