Wind Turbine Payback in Shiawassee County, MI
Wind turbine payback in Shiawassee 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 Shiawassee County, MI averages 6.06 m/s (13.6 mph). A 10 kW turbine there would make about 20,149 kWh a year, worth $4,378 at MI's 21.73¢/kWh. Against an installed cost of about $100,000, that is a payback of 23 years, and the turbine is built to last about 20.
What to do in Shiawassee County
A home turbine is not worth buying for savings in Shiawassee County unless your spot is far windier than the county average, 6.4 m/s at the hub against 6.06 m/s here. Per kW, solar panels would make about 1,107 kWh a year here against the turbine's 2,015, so get a solar quote first.
What would have to change
- Power would have to cost 25¢/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 6.06. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MI
Shiawassee County is the 747th 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 Shiawassee County
January is the strongest month here, at 6.80 m/s and about 2,172 kWh. August is the weakest, 4.83 m/s and 971 kWh, so the best month makes 2.2 times the worst. November to March brings in 50% of the year's output in Shiawassee County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.80 m/s | 2,172 kWh | $472 |
| February | 6.81 m/s | 1,972 kWh | $429 |
| March | 6.52 m/s | 2,000 kWh | $435 |
| April | 6.75 m/s | 2,075 kWh | $451 |
| May | 5.95 m/s | 1,641 kWh | $357 |
| June | 5.31 m/s | 1,205 kWh | $262 |
| July | 4.86 m/s | 986 kWh | $214 |
| August | 4.83 m/s | 971 kWh | $211 |
| September | 5.40 m/s | 1,257 kWh | $273 |
| October | 6.39 m/s | 1,922 kWh | $418 |
| November | 6.65 m/s | 2,016 kWh | $438 |
| December | 6.58 m/s | 2,039 kWh | $443 |
What a taller tower would buy
Measured at 10 m the wind in Shiawassee County averages 4.74 m/s; at 50 m it is 6.8 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 16,313 to 25,602 kWh a year, 57% 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 | 5.54 m/s | 16,313 kWh | 28 years |
| 30 m | 6.06 m/s | 20,184 kWh | 23 years |
| 40 m | 6.47 m/s | 23,175 kWh | 20 years |
| 50 m | 6.8 m/s | 25,602 kWh | 18 years |
Counties around Shiawassee County
4 of the 6 closest counties are windier at turbine height; the windiest, Saginaw County, averages 6.17 m/s.
- Clinton County, MI: 6.06 m/s, 20,149 kWh, payback 23 years (23 mi)
- Genesee County, MI: 6.13 m/s, 20,668 kWh, payback 22 years (23 mi)
- Saginaw County, MI: 6.17 m/s, 20,965 kWh, payback 22 years (26 mi)
- Ingham County, MI: 6.17 m/s, 20,965 kWh, payback 22 years (27 mi)
- Livingston County, MI: 6.09 m/s, 20,371 kWh, payback 23 years (27 mi)
- Gratiot County, MI: 5.82 m/s, 18,374 kWh, payback 25 years (33 mi)
Sun versus wind in Shiawassee County
Shiawassee 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 2,015. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.8 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.