Wind Turbine Payback in Kewaunee County, WI
Wind turbine payback in Kewaunee County
Only just. The money comes back late in the turbine's life.
At 30 m, the height a home turbine tower usually reaches, the wind in Kewaunee County, WI averages 7.28 m/s (16.3 mph). A 10 kW turbine there would make about 29,020 kWh a year, worth $5,528 at WI's 19.05¢/kWh. Against an installed cost of about $100,000, that is a payback of 18 years, and the turbine is built to last about 20.
What to do in Kewaunee County
It is close enough that your own site decides it. If you have open land with no trees or buildings upwind, ask an installer to log the wind at 30 m or higher; anything above 6.9 m/s pays back in time. Per kW, solar panels would make about 1,063 kWh a year here against the turbine's 2,902, so get a solar quote first.
What would have to change
- Power already costs enough here: break-even is 17¢/kWh and WI pays 19.05¢.
- The wind clears the break-even speed of 6.9 m/s at today's price.
Against the rest of WI
Kewaunee County is the 10th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in WI is Manitowoc County at 7.32 m/s, payback 18 years.
Month by month in Kewaunee County
January is the strongest month here, at 8.11 m/s and about 2,933 kWh. August is the weakest, 5.91 m/s and 1,618 kWh, so the best month makes 1.8 times the worst. November to March brings in 48% of the year's output in Kewaunee County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 8.11 m/s | 2,933 kWh | $559 |
| February | 8.01 m/s | 2,600 kWh | $495 |
| March | 7.45 m/s | 2,566 kWh | $489 |
| April | 7.69 m/s | 2,617 kWh | $499 |
| May | 7.05 m/s | 2,329 kWh | $444 |
| June | 6.39 m/s | 1,860 kWh | $354 |
| July | 5.94 m/s | 1,636 kWh | $312 |
| August | 5.91 m/s | 1,618 kWh | $308 |
| September | 6.92 m/s | 2,178 kWh | $415 |
| October | 7.81 m/s | 2,772 kWh | $528 |
| November | 8.04 m/s | 2,800 kWh | $533 |
| December | 8.06 m/s | 2,904 kWh | $553 |
What a taller tower would buy
Measured at 10 m the wind in Kewaunee County averages 6.2 m/s; at 50 m it is 7.84 m/s. That gives a shear exponent of 0.146, typical of very open, smooth ground where height adds little. Going from 20 m to 50 m takes output from 26,024 to 32,801 kWh a year, 26% 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 | 6.86 m/s | 26,024 kWh | 20 years |
| 30 m | 7.28 m/s | 28,996 kWh | 18 years |
| 40 m | 7.59 m/s | 31,136 kWh | 17 years |
| 50 m | 7.84 m/s | 32,801 kWh | 16 years |
Counties around Kewaunee County
1 of the 6 closest counties is windier at turbine height; the windiest, Manitowoc County, averages 7.32 m/s.
- Brown County, WI: 6.34 m/s, 22,225 kWh, payback 24 years (28 mi)
- Manitowoc County, WI: 7.32 m/s, 29,299 kWh, payback 18 years (32 mi)
- Door County, WI: 7.26 m/s, 28,881 kWh, payback 18 years (39 mi)
- Oconto County, WI: 5.93 m/s, 19,186 kWh, payback 27 years (46 mi)
- Outagamie County, WI: 6.01 m/s, 19,778 kWh, payback 27 years (52 mi)
- Calumet County, WI: 6.53 m/s, 23,628 kWh, payback 22 years (52 mi)
Sun versus wind in Kewaunee County
Kewaunee County gets 3.64 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,063 kWh a year; one kW of the turbine above makes 2,902. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 2.7 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.