Wind Turbine Payback in Donley County, TX
Wind turbine payback in Donley 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 Donley County, TX averages 6.29 m/s (14.1 mph). A 10 kW turbine there would make about 21,855 kWh a year, worth $3,503 at TX's 16.03¢/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 Donley County
A home turbine is not worth buying for savings in Donley County unless your spot is far windier than the county average, 7.6 m/s at the hub against 6.29 m/s here. Per kW, solar panels would make about 1,510 kWh a year here against the turbine's 2,186, so get a solar quote first.
What would have to change
- Power would have to cost 23¢/kWh, 1.4 times what TX pays now.
- Or the average wind at the hub would have to be 7.6 m/s instead of 6.29. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of TX
Donley County is the 482nd windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in TX is Dallam County at 6.82 m/s, payback 24 years.
Month by month in Donley County
April is the strongest month here, at 7.26 m/s and about 2,374 kWh. August is the weakest, 5.37 m/s and 1,282 kWh, so the best month makes 1.9 times the worst. November to March brings in 44% of the year's output in Donley County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.31 m/s | 1,872 kWh | $300 |
| February | 6.46 m/s | 1,771 kWh | $284 |
| March | 6.72 m/s | 2,122 kWh | $340 |
| April | 7.26 m/s | 2,374 kWh | $381 |
| May | 6.48 m/s | 1,972 kWh | $316 |
| June | 6.38 m/s | 1,849 kWh | $296 |
| July | 5.59 m/s | 1,419 kWh | $227 |
| August | 5.37 m/s | 1,282 kWh | $206 |
| September | 5.74 m/s | 1,464 kWh | $235 |
| October | 6.32 m/s | 1,877 kWh | $301 |
| November | 6.54 m/s | 1,947 kWh | $312 |
| December | 6.34 m/s | 1,888 kWh | $303 |
What a taller tower would buy
Measured at 10 m the wind in Donley County averages 4.92 m/s; at 50 m it is 7.05 m/s. That gives a shear exponent of 0.224, typical of ordinary open country. Going from 20 m to 50 m takes output from 17,799 to 27,400 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 | 5.74 m/s | 17,799 kWh | 35 years |
| 30 m | 6.29 m/s | 21,838 kWh | 29 years |
| 40 m | 6.71 m/s | 24,920 kWh | 25 years |
| 50 m | 7.05 m/s | 27,400 kWh | 23 years |
Counties around Donley County
4 of the 6 closest counties are windier at turbine height; the windiest, Gray County, averages 6.7 m/s.
- Armstrong County, TX: 6.44 m/s, 22,964 kWh, payback 27 years (31 mi)
- Collingsworth County, TX: 6.22 m/s, 21,336 kWh, payback 29 years (31 mi)
- Gray County, TX: 6.7 m/s, 24,874 kWh, payback 25 years (31 mi)
- Briscoe County, TX: 6.35 m/s, 22,299 kWh, payback 28 years (37 mi)
- Hall County, TX: 6.1 m/s, 20,446 kWh, payback 31 years (37 mi)
- Carson County, TX: 6.7 m/s, 24,874 kWh, payback 25 years (44 mi)
Sun versus wind in Donley County
Donley County gets 5.17 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,510 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 1.4 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.