TurbinePayback

Wind Turbine Payback in Decatur County, KS

Wind turbine payback in Decatur 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 Decatur County, KS averages 6.29 m/s (14.1 mph). A 10 kW turbine there would make about 21,855 kWh a year, worth $3,335 at KS's 15.26¢/kWh. Against an installed cost of about $100,000, that is a payback of 30 years, and the turbine is built to last about 20.

What to do in Decatur County

A home turbine is not worth buying for savings in Decatur County unless your spot is far windier than the county average, 7.8 m/s at the hub against 6.29 m/s here. Per kW, solar panels would make about 1,381 kWh a year here against the turbine's 2,186, so get a solar quote first.

What would have to change

Against the rest of KS

Decatur County is the 482nd windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in KS is Edwards County at 6.68 m/s, payback 27 years.

Month by month in Decatur County

April is the strongest month here, at 7.03 m/s and about 2,242 kWh. August is the weakest, 5.54 m/s and 1,387 kWh, so the best month makes 1.6 times the worst. November to March brings in 43% of the year's output in Decatur County.

MonthWind at 30 mOutputWorth
January6.28 m/s1,852 kWh$283
February6.34 m/s1,703 kWh$260
March6.61 m/s2,059 kWh$314
April7.03 m/s2,242 kWh$342
May6.41 m/s1,930 kWh$295
June6.12 m/s1,694 kWh$259
July5.65 m/s1,453 kWh$222
August5.54 m/s1,387 kWh$212
September6.33 m/s1,819 kWh$278
October6.50 m/s1,986 kWh$303
November6.43 m/s1,879 kWh$287
December6.26 m/s1,840 kWh$281

What a taller tower would buy

Measured at 10 m the wind in Decatur County averages 4.94 m/s; at 50 m it is 7.04 m/s. That gives a shear exponent of 0.220, typical of ordinary open country. Going from 20 m to 50 m takes output from 17,893 to 27,328 kWh a year, 53% 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 m5.75 m/s17,893 kWh37 years
30 m6.29 m/s21,867 kWh30 years
40 m6.7 m/s24,894 kWh26 years
50 m7.04 m/s27,328 kWh24 years

Counties around Decatur County

3 of the 6 closest counties are windier at turbine height; the windiest, Sheridan County, averages 6.44 m/s.

Sun versus wind in Decatur County

Decatur County gets 4.73 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,381 kWh a year; one kW of the turbine above makes 2,186. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.6 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.