Wind Turbine Payback in Eaton County, MI
Wind turbine payback in Eaton 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 Eaton County, MI averages 6.11 m/s (13.7 mph). A 10 kW turbine there would make about 20,520 kWh a year, worth $4,459 at MI's 21.73¢/kWh. Against an installed cost of about $100,000, that is a payback of 22 years, and the turbine is built to last about 20.
What to do in Eaton County
A home turbine is not worth buying for savings in Eaton County unless your spot is far windier than the county average, 6.4 m/s at the hub against 6.11 m/s here. Per kW, solar panels would make about 1,107 kWh a year here against the turbine's 2,052, so get a solar quote first.
What would have to change
- Power would have to cost 24¢/kWh, 1.1 times what MI pays now.
- Or the average wind at the hub would have to be 6.4 m/s instead of 6.11. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MI
Eaton County is the 675th 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 Eaton County
January is the strongest month here, at 6.89 m/s and about 2,227 kWh. August is the weakest, 4.83 m/s and 966 kWh, so the best month makes 2.3 times the worst. November to March brings in 51% of the year's output in Eaton County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.89 m/s | 2,227 kWh | $484 |
| February | 6.87 m/s | 2,001 kWh | $435 |
| March | 6.59 m/s | 2,045 kWh | $444 |
| April | 6.83 m/s | 2,123 kWh | $461 |
| May | 6.00 m/s | 1,675 kWh | $364 |
| June | 5.32 m/s | 1,210 kWh | $263 |
| July | 4.84 m/s | 976 kWh | $212 |
| August | 4.83 m/s | 966 kWh | $210 |
| September | 5.45 m/s | 1,288 kWh | $280 |
| October | 6.42 m/s | 1,939 kWh | $421 |
| November | 6.70 m/s | 2,043 kWh | $444 |
| December | 6.65 m/s | 2,084 kWh | $453 |
What a taller tower would buy
Measured at 10 m the wind in Eaton County averages 4.78 m/s; at 50 m it is 6.85 m/s. That gives a shear exponent of 0.224, typical of ordinary open country. Going from 20 m to 50 m takes output from 16,609 to 25,964 kWh a year, 56% 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 | 5.58 m/s | 16,609 kWh | 28 years |
| 30 m | 6.11 m/s | 20,515 kWh | 22 years |
| 40 m | 6.52 m/s | 23,525 kWh | 20 years |
| 50 m | 6.85 m/s | 25,964 kWh | 18 years |
Counties around Eaton County
2 of the 6 closest counties are windier at turbine height; the windiest, Ingham County, averages 6.17 m/s.
- Barry County, MI: 6.07 m/s, 20,223 kWh, payback 23 years (24 mi)
- Ingham County, MI: 6.17 m/s, 20,965 kWh, payback 22 years (24 mi)
- Calhoun County, MI: 6.1 m/s, 20,446 kWh, payback 23 years (25 mi)
- Ionia County, MI: 6 m/s, 19,704 kWh, payback 23 years (27 mi)
- Clinton County, MI: 6.06 m/s, 20,149 kWh, payback 23 years (28 mi)
- Jackson County, MI: 6.12 m/s, 20,594 kWh, payback 22 years (32 mi)
Sun versus wind in Eaton County
Eaton County gets 3.79 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,107 kWh a year; one kW of the turbine above makes 2,052. 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.