Wind Turbine Payback in Smith County, KS
Wind turbine payback in Smith 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 Smith County, KS averages 6.38 m/s (14.3 mph). A 10 kW turbine there would make about 22,521 kWh a year, worth $3,437 at KS's 15.26¢/kWh. Against an installed cost of about $100,000, that is a payback of 29 years, and the turbine is built to last about 20.
What to do in Smith County
A home turbine is not worth buying for savings in Smith County unless your spot is far windier than the county average, 7.8 m/s at the hub against 6.38 m/s here. Per kW, solar panels would make about 1,332 kWh a year here against the turbine's 2,252, so get a solar quote first.
What would have to change
- Power would have to cost 22¢/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 6.38. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of KS
Smith County is the 359th 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 Smith County
April is the strongest month here, at 7.25 m/s and about 2,370 kWh. August is the weakest, 5.42 m/s and 1,314 kWh, so the best month makes 1.8 times the worst. November to March brings in 43% of the year's output in Smith County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.29 m/s | 1,855 kWh | $283 |
| February | 6.42 m/s | 1,752 kWh | $267 |
| March | 6.84 m/s | 2,200 kWh | $336 |
| April | 7.25 m/s | 2,370 kWh | $362 |
| May | 6.57 m/s | 2,029 kWh | $310 |
| June | 6.32 m/s | 1,812 kWh | $277 |
| July | 5.55 m/s | 1,391 kWh | $212 |
| August | 5.42 m/s | 1,314 kWh | $201 |
| September | 6.45 m/s | 1,893 kWh | $289 |
| October | 6.63 m/s | 2,068 kWh | $316 |
| November | 6.55 m/s | 1,953 kWh | $298 |
| December | 6.27 m/s | 1,844 kWh | $281 |
What a taller tower would buy
Measured at 10 m the wind in Smith County averages 5 m/s; at 50 m it is 7.14 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 18,456 to 28,038 kWh a year, 52% 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 | 5.83 m/s | 18,456 kWh | 36 years |
| 30 m | 6.38 m/s | 22,505 kWh | 29 years |
| 40 m | 6.8 m/s | 25,576 kWh | 26 years |
| 50 m | 7.14 m/s | 28,038 kWh | 23 years |
Counties around Smith County
1 of the 6 closest counties is windier at turbine height; the windiest, Jewell County, averages 6.4 m/s.
- Franklin County, NE: 6.38 m/s, 22,521 kWh, payback 34 years (29 mi)
- Phillips County, KS: 6.34 m/s, 22,225 kWh, payback 30 years (30 mi)
- Jewell County, KS: 6.4 m/s, 22,669 kWh, payback 29 years (30 mi)
- Osborne County, KS: 6.27 m/s, 21,706 kWh, payback 30 years (30 mi)
- Webster County, NE: 6.38 m/s, 22,521 kWh, payback 34 years (31 mi)
- Mitchell County, KS: 6.26 m/s, 21,632 kWh, payback 30 years (41 mi)
Sun versus wind in Smith County
Smith County gets 4.56 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,332 kWh a year; one kW of the turbine above makes 2,252. 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.