Wind Turbine Payback in Gray County, KS
Wind turbine payback in Gray 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 Gray County, KS averages 6.52 m/s (14.6 mph). A 10 kW turbine there would make about 23,554 kWh a year, worth $3,594 at KS's 15.26¢/kWh. Against an installed cost of about $100,000, that is a payback of 28 years, and the turbine is built to last about 20.
What to do in Gray County
A home turbine is not worth buying for savings in Gray County unless your spot is far windier than the county average, 7.8 m/s at the hub against 6.52 m/s here. Per kW, solar panels would make about 1,448 kWh a year here against the turbine's 2,355, so get a solar quote first.
What would have to change
- Power would have to cost 21¢/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 6.52. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of KS
Gray County is the 180th 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 Gray County
April is the strongest month here, at 7.32 m/s and about 2,409 kWh. August is the weakest, 5.85 m/s and 1,582 kWh, so the best month makes 1.5 times the worst. November to March brings in 41% of the year's output in Gray County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.18 m/s | 1,784 kWh | $272 |
| February | 6.42 m/s | 1,749 kWh | $267 |
| March | 6.83 m/s | 2,193 kWh | $335 |
| April | 7.32 m/s | 2,409 kWh | $368 |
| May | 6.74 m/s | 2,137 kWh | $326 |
| June | 6.81 m/s | 2,111 kWh | $322 |
| July | 5.99 m/s | 1,666 kWh | $254 |
| August | 5.85 m/s | 1,582 kWh | $241 |
| September | 6.63 m/s | 2,004 kWh | $306 |
| October | 6.61 m/s | 2,060 kWh | $314 |
| November | 6.62 m/s | 1,998 kWh | $305 |
| December | 6.27 m/s | 1,846 kWh | $282 |
What a taller tower would buy
Measured at 10 m the wind in Gray County averages 5.14 m/s; at 50 m it is 7.29 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 19,523 to 29,090 kWh a year, 49% 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 | 5.98 m/s | 19,523 kWh | 34 years |
| 30 m | 6.53 m/s | 23,592 kWh | 28 years |
| 40 m | 6.95 m/s | 26,652 kWh | 25 years |
| 50 m | 7.29 m/s | 29,090 kWh | 23 years |
Counties around Gray County
3 of the 6 closest counties are windier at turbine height; the windiest, Hodgeman County, averages 6.66 m/s.
- Finney County, KS: 6.56 m/s, 23,849 kWh, payback 28 years (26 mi)
- Haskell County, KS: 6.52 m/s, 23,554 kWh, payback 28 years (27 mi)
- Ford County, KS: 6.58 m/s, 23,996 kWh, payback 27 years (31 mi)
- Meade County, KS: 6.52 m/s, 23,554 kWh, payback 28 years (35 mi)
- Hodgeman County, KS: 6.66 m/s, 24,582 kWh, payback 27 years (38 mi)
- Seward County, KS: 6.52 m/s, 23,554 kWh, payback 28 years (45 mi)
Sun versus wind in Gray County
Gray County gets 4.96 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,448 kWh a year; one kW of the turbine above makes 2,355. 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.