Wind Turbine Payback in Columbia County, WI
Wind turbine payback in Columbia 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 Columbia County, WI averages 6.06 m/s (13.6 mph). A 10 kW turbine there would make about 20,149 kWh a year, worth $3,838 at WI's 19.05¢/kWh. Against an installed cost of about $100,000, that is a payback of 26 years, and the turbine is built to last about 20.
What to do in Columbia County
A home turbine is not worth buying for savings in Columbia County unless your spot is far windier than the county average, 6.9 m/s at the hub against 6.06 m/s here. Per kW, solar panels would make about 1,124 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, 1.3 times what WI pays now.
- Or the average wind at the hub would have to be 6.9 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 WI
Columbia County is the 747th 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 Columbia County
April is the strongest month here, at 6.82 m/s and about 2,119 kWh. August is the weakest, 4.86 m/s and 985 kWh, so the best month makes 2.2 times the worst. November to March brings in 48% of the year's output in Columbia County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.61 m/s | 2,057 kWh | $392 |
| February | 6.72 m/s | 1,918 kWh | $365 |
| March | 6.48 m/s | 1,979 kWh | $377 |
| April | 6.82 m/s | 2,119 kWh | $404 |
| May | 6.07 m/s | 1,715 kWh | $327 |
| June | 5.41 m/s | 1,267 kWh | $241 |
| July | 4.93 m/s | 1,025 kWh | $195 |
| August | 4.86 m/s | 985 kWh | $188 |
| September | 5.70 m/s | 1,437 kWh | $274 |
| October | 6.37 m/s | 1,906 kWh | $363 |
| November | 6.45 m/s | 1,893 kWh | $361 |
| December | 6.34 m/s | 1,889 kWh | $360 |
What a taller tower would buy
Measured at 10 m the wind in Columbia County averages 4.75 m/s; at 50 m it is 6.78 m/s. That gives a shear exponent of 0.221, typical of ordinary open country. Going from 20 m to 50 m takes output from 16,305 to 25,457 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 | 5.54 m/s | 16,305 kWh | 32 years |
| 30 m | 6.06 m/s | 20,121 kWh | 26 years |
| 40 m | 6.45 m/s | 23,066 kWh | 23 years |
| 50 m | 6.78 m/s | 25,457 kWh | 21 years |
Counties around Columbia County
5 of the 6 closest counties are windier at turbine height; the windiest, Green Lake County, averages 6.12 m/s.
- Marquette County, WI: 6.06 m/s, 20,149 kWh, payback 26 years (25 mi)
- Green Lake County, WI: 6.12 m/s, 20,594 kWh, payback 26 years (28 mi)
- Dane County, WI: 6.08 m/s, 20,297 kWh, payback 26 years (28 mi)
- Sauk County, WI: 6.07 m/s, 20,223 kWh, payback 26 years (31 mi)
- Dodge County, WI: 6.09 m/s, 20,371 kWh, payback 26 years (32 mi)
- Adams County, WI: 6.11 m/s, 20,520 kWh, payback 26 years (41 mi)
Sun versus wind in Columbia County
Columbia County gets 3.85 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,124 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.