Wind Turbine Payback in Mercer County, ND
Wind turbine payback in Mercer 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 Mercer County, ND averages 6.52 m/s (14.6 mph). A 10 kW turbine there would make about 23,554 kWh a year, worth $2,935 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 Mercer County
A home turbine is not worth buying for savings in Mercer County unless your spot is far windier than the county average, 9.1 m/s at the hub against 6.52 m/s here. Per kW, solar panels would make about 1,150 kWh a year here against the turbine's 2,355, 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 6.52. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of ND
Mercer County is the 180th 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 Mercer County
October is the strongest month here, at 7.04 m/s and about 2,323 kWh. July is the weakest, 5.74 m/s and 1,512 kWh, so the best month makes 1.5 times the worst. November to March brings in 43% of the year's output in Mercer County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.74 m/s | 2,135 kWh | $266 |
| February | 6.28 m/s | 1,673 kWh | $208 |
| March | 6.81 m/s | 2,179 kWh | $272 |
| April | 6.85 m/s | 2,136 kWh | $266 |
| May | 6.67 m/s | 2,095 kWh | $261 |
| June | 6.17 m/s | 1,721 kWh | $214 |
| July | 5.74 m/s | 1,512 kWh | $188 |
| August | 5.86 m/s | 1,585 kWh | $197 |
| September | 6.50 m/s | 1,924 kWh | $240 |
| October | 7.04 m/s | 2,323 kWh | $289 |
| November | 6.89 m/s | 2,157 kWh | $269 |
| December | 6.65 m/s | 2,079 kWh | $259 |
What a taller tower would buy
Measured at 10 m the wind in Mercer County averages 5.23 m/s; at 50 m it is 7.22 m/s. That gives a shear exponent of 0.200, typical of ordinary open country. Going from 20 m to 50 m takes output from 19,786 to 28,601 kWh a year, 45% 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 | 6.01 m/s | 19,786 kWh | 41 years |
| 30 m | 6.52 m/s | 23,545 kWh | 34 years |
| 40 m | 6.9 m/s | 26,360 kWh | 30 years |
| 50 m | 7.22 m/s | 28,601 kWh | 28 years |
Counties around Mercer County
3 of the 6 closest counties are windier at turbine height; the windiest, Stark County, averages 6.7 m/s.
- Oliver County, ND: 6.49 m/s, 23,333 kWh, payback 34 years (27 mi)
- McLean County, ND: 6.52 m/s, 23,554 kWh, payback 34 years (31 mi)
- Dunn County, ND: 6.57 m/s, 23,922 kWh, payback 34 years (37 mi)
- Morton County, ND: 6.53 m/s, 23,628 kWh, payback 34 years (48 mi)
- Stark County, ND: 6.7 m/s, 24,874 kWh, payback 32 years (52 mi)
- Ward County, ND: 6.49 m/s, 23,333 kWh, payback 34 years (64 mi)
Sun versus wind in Mercer County
Mercer County gets 3.94 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,150 kWh a year; one kW of the turbine above makes 2,355. 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.