Wind Turbine Payback in Grant County, KS
Wind turbine payback in Grant 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 Grant County, KS averages 6.43 m/s (14.4 mph). A 10 kW turbine there would make about 22,891 kWh a year, worth $3,493 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 Grant County
A home turbine is not worth buying for savings in Grant County unless your spot is far windier than the county average, 7.8 m/s at the hub against 6.43 m/s here. Per kW, solar panels would make about 1,472 kWh a year here against the turbine's 2,289, so get a solar quote first.
What would have to change
- Power would have to cost 22¢/kWh, 1.4 times what KS pays now.
- Or the average wind at the hub would have to be 7.8 m/s instead of 6.43. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of KS
Grant County is the 290th 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 Grant County
April is the strongest month here, at 7.19 m/s and about 2,335 kWh. August is the weakest, 5.82 m/s and 1,557 kWh, so the best month makes 1.5 times the worst. November to March brings in 40% of the year's output in Grant County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.07 m/s | 1,720 kWh | $262 |
| February | 6.32 m/s | 1,691 kWh | $258 |
| March | 6.69 m/s | 2,107 kWh | $322 |
| April | 7.19 m/s | 2,335 kWh | $356 |
| May | 6.65 m/s | 2,080 kWh | $317 |
| June | 6.75 m/s | 2,077 kWh | $317 |
| July | 5.96 m/s | 1,647 kWh | $251 |
| August | 5.82 m/s | 1,557 kWh | $238 |
| September | 6.58 m/s | 1,969 kWh | $300 |
| October | 6.49 m/s | 1,979 kWh | $302 |
| November | 6.53 m/s | 1,942 kWh | $296 |
| December | 6.17 m/s | 1,782 kWh | $272 |
What a taller tower would buy
Measured at 10 m the wind in Grant County averages 5.06 m/s; at 50 m it is 7.19 m/s. That gives a shear exponent of 0.218, typical of ordinary open country. Going from 20 m to 50 m takes output from 18,876 to 28,390 kWh a year, 50% 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 | 5.89 m/s | 18,876 kWh | 35 years |
| 30 m | 6.43 m/s | 22,908 kWh | 29 years |
| 40 m | 6.85 m/s | 25,954 kWh | 25 years |
| 50 m | 7.19 m/s | 28,390 kWh | 23 years |
Counties around Grant County
5 of the 6 closest counties are windier at turbine height; the windiest, Morton County, averages 6.6 m/s.
- Haskell County, KS: 6.52 m/s, 23,554 kWh, payback 28 years (23 mi)
- Stevens County, KS: 6.54 m/s, 23,702 kWh, payback 28 years (24 mi)
- Stanton County, KS: 6.44 m/s, 22,964 kWh, payback 29 years (27 mi)
- Kearny County, KS: 6.4 m/s, 22,669 kWh, payback 29 years (31 mi)
- Seward County, KS: 6.52 m/s, 23,554 kWh, payback 28 years (35 mi)
- Morton County, KS: 6.6 m/s, 24,142 kWh, payback 27 years (38 mi)
Sun versus wind in Grant County
Grant County gets 5.04 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,472 kWh a year; one kW of the turbine above makes 2,289. 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.