TurbinePayback

Wind Turbine Payback in Winnebago County, WI

Wind turbine payback in Winnebago 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 Winnebago County, WI averages 6.12 m/s (13.7 mph). A 10 kW turbine there would make about 20,594 kWh a year, worth $3,923 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 Winnebago County

A home turbine is not worth buying for savings in Winnebago County unless your spot is far windier than the county average, 6.9 m/s at the hub against 6.12 m/s here. Per kW, solar panels would make about 1,113 kWh a year here against the turbine's 2,059, so get a solar quote first.

What would have to change

Against the rest of WI

Winnebago County is the 664th 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 Winnebago County

April is the strongest month here, at 6.85 m/s and about 2,132 kWh. August is the weakest, 4.99 m/s and 1,061 kWh, so the best month makes 2.0 times the worst. November to March brings in 48% of the year's output in Winnebago County.

MonthWind at 30 mOutputWorth
January6.63 m/s2,071 kWh$395
February6.78 m/s1,955 kWh$372
March6.53 m/s2,004 kWh$382
April6.85 m/s2,132 kWh$406
May6.10 m/s1,739 kWh$331
June5.45 m/s1,289 kWh$246
July5.04 m/s1,087 kWh$207
August4.99 m/s1,061 kWh$202
September5.78 m/s1,487 kWh$283
October6.44 m/s1,948 kWh$371
November6.47 m/s1,907 kWh$363
December6.43 m/s1,942 kWh$370

What a taller tower would buy

Measured at 10 m the wind in Winnebago County averages 4.82 m/s; at 50 m it is 6.84 m/s. That gives a shear exponent of 0.217, typical of ordinary open country. Going from 20 m to 50 m takes output from 16,810 to 25,892 kWh a year, 54% more, before counting the extra cost of the taller tower. Why tower height decides it explains the shear behind these numbers.

Hub heightAverage windOutputPayback
20 m5.61 m/s16,810 kWh31 years
30 m6.12 m/s20,611 kWh26 years
40 m6.52 m/s23,530 kWh22 years
50 m6.84 m/s25,892 kWh20 years

Counties around Winnebago County

1 of the 6 closest counties is windier at turbine height; the windiest, Calumet County, averages 6.53 m/s.

Sun versus wind in Winnebago County

Winnebago County gets 3.81 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,113 kWh a year; one kW of the turbine above makes 2,059. 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.