Wind Turbine Payback in Clinton County, IA
Wind turbine payback in Clinton 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 Clinton County, IA averages 5.95 m/s (13.3 mph). A 10 kW turbine there would make about 19,334 kWh a year, worth $2,813 at IA's 14.55¢/kWh. Against an installed cost of about $100,000, that is a payback of 36 years, and the turbine is built to last about 20.
What to do in Clinton County
A home turbine is not worth buying for savings in Clinton County unless your spot is far windier than the county average, 8.1 m/s at the hub against 5.95 m/s here. Per kW, solar panels would make about 1,165 kWh a year here against the turbine's 1,933, so get a solar quote first.
What would have to change
- Power would have to cost 26¢/kWh, 1.8 times what IA pays now.
- Or the average wind at the hub would have to be 8.1 m/s instead of 5.95. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of IA
Clinton County is the 914th 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 Clinton County
April is the strongest month here, at 6.85 m/s and about 2,136 kWh. August is the weakest, 4.66 m/s and 874 kWh, so the best month makes 2.4 times the worst. November to March brings in 48% of the year's output in Clinton County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.40 m/s | 1,925 kWh | $280 |
| February | 6.45 m/s | 1,769 kWh | $257 |
| March | 6.55 m/s | 2,020 kWh | $294 |
| April | 6.85 m/s | 2,136 kWh | $311 |
| May | 6.08 m/s | 1,723 kWh | $251 |
| June | 5.32 m/s | 1,214 kWh | $177 |
| July | 4.66 m/s | 879 kWh | $128 |
| August | 4.66 m/s | 874 kWh | $127 |
| September | 5.52 m/s | 1,329 kWh | $193 |
| October | 6.27 m/s | 1,841 kWh | $268 |
| November | 6.45 m/s | 1,895 kWh | $276 |
| December | 6.18 m/s | 1,785 kWh | $260 |
What a taller tower would buy
Measured at 10 m the wind in Clinton County averages 4.63 m/s; at 50 m it is 6.68 m/s. That gives a shear exponent of 0.228, typical of ordinary open country. Going from 20 m to 50 m takes output from 15,466 to 24,728 kWh a year, 60% 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 | 5.42 m/s | 15,466 kWh | 44 years |
| 30 m | 5.95 m/s | 19,301 kWh | 36 years |
| 40 m | 6.35 m/s | 22,289 kWh | 31 years |
| 50 m | 6.68 m/s | 24,728 kWh | 28 years |
Counties around Clinton County
3 of the 6 closest counties are windier at turbine height; the windiest, Cedar County, averages 6.01 m/s.
- Scott County, IA: 5.99 m/s, 19,630 kWh, payback 35 years (18 mi)
- Jackson County, IA: 5.95 m/s, 19,334 kWh, payback 36 years (19 mi)
- Rock Island County, IL: 5.99 m/s, 19,630 kWh, payback 27 years (30 mi)
- Cedar County, IA: 6.01 m/s, 19,778 kWh, payback 35 years (32 mi)
- Carroll County, IL: 5.92 m/s, 19,112 kWh, payback 27 years (34 mi)
- Whiteside County, IL: 5.92 m/s, 19,112 kWh, payback 27 years (34 mi)
Sun versus wind in Clinton County
Clinton County gets 3.99 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,165 kWh a year; one kW of the turbine above makes 1,933. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.7 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.