Wind Turbine Payback in Greenwood County, KS
Wind turbine payback in Greenwood 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 Greenwood County, KS averages 6.33 m/s (14.2 mph). A 10 kW turbine there would make about 22,151 kWh a year, worth $3,380 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 Greenwood County
A home turbine is not worth buying for savings in Greenwood County unless your spot is far windier than the county average, 7.8 m/s at the hub against 6.33 m/s here. Per kW, solar panels would make about 1,314 kWh a year here against the turbine's 2,215, so get a solar quote first.
What would have to change
- Power would have to cost 23¢/kWh, 1.5 times what KS pays now.
- Or the average wind at the hub would have to be 7.8 m/s instead of 6.33. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of KS
Greenwood County is the 441st 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 Greenwood County
April is the strongest month here, at 7.38 m/s and about 2,441 kWh. August is the weakest, 5.10 m/s and 1,120 kWh, so the best month makes 2.2 times the worst. November to March brings in 46% of the year's output in Greenwood County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.56 m/s | 2,024 kWh | $309 |
| February | 6.58 m/s | 1,843 kWh | $281 |
| March | 7.05 m/s | 2,326 kWh | $355 |
| April | 7.38 m/s | 2,441 kWh | $372 |
| May | 6.40 m/s | 1,924 kWh | $294 |
| June | 6.11 m/s | 1,688 kWh | $258 |
| July | 5.19 m/s | 1,178 kWh | $180 |
| August | 5.10 m/s | 1,120 kWh | $171 |
| September | 5.82 m/s | 1,509 kWh | $230 |
| October | 6.58 m/s | 2,035 kWh | $311 |
| November | 6.81 m/s | 2,108 kWh | $322 |
| December | 6.49 m/s | 1,979 kWh | $302 |
What a taller tower would buy
Measured at 10 m the wind in Greenwood County averages 4.94 m/s; at 50 m it is 7.11 m/s. That gives a shear exponent of 0.226, typical of ordinary open country. Going from 20 m to 50 m takes output from 18,080 to 27,826 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 height | Average wind | Output | Payback |
|---|---|---|---|
| 20 m | 5.78 m/s | 18,080 kWh | 36 years |
| 30 m | 6.33 m/s | 22,186 kWh | 30 years |
| 40 m | 6.76 m/s | 25,314 kWh | 26 years |
| 50 m | 7.11 m/s | 27,826 kWh | 24 years |
Counties around Greenwood County
2 of the 6 closest counties are windier at turbine height; the windiest, Butler County, averages 6.48 m/s.
- Woodson County, KS: 6.18 m/s, 21,039 kWh, payback 31 years (26 mi)
- Elk County, KS: 6.26 m/s, 21,632 kWh, payback 30 years (29 mi)
- Butler County, KS: 6.48 m/s, 23,260 kWh, payback 28 years (33 mi)
- Chase County, KS: 6.46 m/s, 23,112 kWh, payback 28 years (35 mi)
- Wilson County, KS: 6.09 m/s, 20,371 kWh, payback 32 years (35 mi)
- Coffey County, KS: 6.18 m/s, 21,039 kWh, payback 31 years (37 mi)
Sun versus wind in Greenwood County
Greenwood County gets 4.5 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,314 kWh a year; one kW of the turbine above makes 2,215. 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.