Wind Turbine Payback in Iron County, MI
Wind turbine payback in Iron 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 Iron County, MI averages 4.06 m/s (9.1 mph). A 10 kW turbine there would make about 6,883 kWh a year, worth $1,496 at MI's 21.73¢/kWh. Against an installed cost of about $100,000, that is a payback of 67 years, and the turbine is built to last about 20.
What to do in Iron County
A home turbine is not worth buying for savings in Iron County unless your spot is far windier than the county average, 6.4 m/s at the hub against 4.06 m/s here. Per kW, solar panels would make about 1,040 kWh a year here against the turbine's 688, so get a solar quote first.
What would have to change
- Power would have to cost 73¢/kWh, 3.3 times what MI pays now.
- Or the average wind at the hub would have to be 6.4 m/s instead of 4.06. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MI
Iron County is the 2,021st windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in MI is Keweenaw County at 7.4 m/s, payback 15 years.
Month by month in Iron County
February is the strongest month here, at 4.87 m/s and about 896 kWh. July is the weakest, 3.38 m/s and 327 kWh, so the best month makes 2.7 times the worst. November to March brings in 55% of the year's output in Iron County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.67 m/s | 884 kWh | $192 |
| February | 4.87 m/s | 896 kWh | $195 |
| March | 4.53 m/s | 807 kWh | $175 |
| April | 4.40 m/s | 720 kWh | $156 |
| May | 3.82 m/s | 485 kWh | $105 |
| June | 3.47 m/s | 345 kWh | $75 |
| July | 3.38 m/s | 327 kWh | $71 |
| August | 3.40 m/s | 335 kWh | $73 |
| September | 3.75 m/s | 441 kWh | $96 |
| October | 3.99 m/s | 555 kWh | $121 |
| November | 4.19 m/s | 622 kWh | $135 |
| December | 4.31 m/s | 700 kWh | $152 |
What a taller tower would buy
Measured at 10 m the wind in Iron County averages 2.66 m/s; at 50 m it is 4.94 m/s. That gives a shear exponent of 0.385, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 4,216 to 12,132 kWh a year, 188% 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 | 3.47 m/s | 4,216 kWh | over 100 years |
| 30 m | 4.06 m/s | 6,872 kWh | 67 years |
| 40 m | 4.53 m/s | 9,539 kWh | 48 years |
| 50 m | 4.94 m/s | 12,132 kWh | 38 years |
Counties around Iron County
4 of the 6 closest counties are windier at turbine height; the windiest, Forest County, averages 4.98 m/s.
- Florence County, WI: 3.95 m/s, 6,329 kWh, payback 83 years (22 mi)
- Dickinson County, MI: 3.95 m/s, 6,329 kWh, payback 73 years (34 mi)
- Forest County, WI: 4.98 m/s, 12,400 kWh, payback 42 years (37 mi)
- Baraga County, MI: 4.27 m/s, 8,008 kWh, payback 58 years (37 mi)
- Vilas County, WI: 4.67 m/s, 10,382 kWh, payback 51 years (47 mi)
- Marquette County, MI: 4.81 m/s, 11,276 kWh, payback 41 years (57 mi)
Sun versus wind in Iron County
Iron County gets 3.56 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,040 kWh a year; one kW of the turbine above makes 688. Kilowatt for kilowatt, panels make 1.5 times as much here as the turbine. 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.