Wind Turbine Payback in Emmet County, IA
Wind turbine payback in Emmet 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 Emmet County, IA averages 6.5 m/s (14.5 mph). A 10 kW turbine there would make about 23,407 kWh a year, worth $3,406 at IA's 14.55¢/kWh. Against an installed cost of about $100,000, that is a payback of 29 years, and the turbine is built to last about 20.
What to do in Emmet County
A home turbine is not worth buying for savings in Emmet County unless your spot is far windier than the county average, 8.1 m/s at the hub against 6.5 m/s here. Per kW, solar panels would make about 1,168 kWh a year here against the turbine's 2,341, so get a solar quote first.
What would have to change
- Power would have to cost 21¢/kWh, 1.5 times what IA pays now.
- Or the average wind at the hub would have to be 8.1 m/s instead of 6.5. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of IA
Emmet County is the 208th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in IA is Dickinson County at 6.59 m/s, payback 29 years.
Month by month in Emmet County
April is the strongest month here, at 7.32 m/s and about 2,409 kWh. August is the weakest, 5.28 m/s and 1,230 kWh, so the best month makes 2.0 times the worst. November to March brings in 46% of the year's output in Emmet County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.90 m/s | 2,235 kWh | $325 |
| February | 6.88 m/s | 2,009 kWh | $292 |
| March | 6.98 m/s | 2,284 kWh | $332 |
| April | 7.32 m/s | 2,409 kWh | $351 |
| May | 6.69 m/s | 2,108 kWh | $307 |
| June | 6.02 m/s | 1,631 kWh | $237 |
| July | 5.29 m/s | 1,235 kWh | $180 |
| August | 5.28 m/s | 1,230 kWh | $179 |
| September | 6.33 m/s | 1,822 kWh | $265 |
| October | 6.79 m/s | 2,169 kWh | $316 |
| November | 6.92 m/s | 2,174 kWh | $316 |
| December | 6.73 m/s | 2,130 kWh | $310 |
What a taller tower would buy
Measured at 10 m the wind in Emmet County averages 5.16 m/s; at 50 m it is 7.24 m/s. That gives a shear exponent of 0.210, typical of ordinary open country. Going from 20 m to 50 m takes output from 19,502 to 28,741 kWh a year, 47% 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 | 5.97 m/s | 19,502 kWh | 35 years |
| 30 m | 6.5 m/s | 23,433 kWh | 29 years |
| 40 m | 6.91 m/s | 26,387 kWh | 26 years |
| 50 m | 7.24 m/s | 28,741 kWh | 24 years |
Counties around Emmet County
2 of the 6 closest counties are windier at turbine height; the windiest, Dickinson County, averages 6.59 m/s.
- Palo Alto County, IA: 6.46 m/s, 23,112 kWh, payback 30 years (21 mi)
- Martin County, MN: 6.5 m/s, 23,407 kWh, payback 26 years (22 mi)
- Kossuth County, IA: 6.46 m/s, 23,112 kWh, payback 30 years (26 mi)
- Dickinson County, IA: 6.59 m/s, 24,069 kWh, payback 29 years (26 mi)
- Jackson County, MN: 6.59 m/s, 24,069 kWh, payback 25 years (31 mi)
- Clay County, IA: 6.48 m/s, 23,260 kWh, payback 30 years (32 mi)
Sun versus wind in Emmet County
Emmet County gets 4 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,168 kWh a year; one kW of the turbine above makes 2,341. 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.