Wind Turbine Payback in Gray County, TX
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, TX averages 6.7 m/s (15 mph). A 10 kW turbine there would make about 24,874 kWh a year, worth $3,987 at TX's 16.03¢/kWh. Against an installed cost of about $100,000, that is a payback of 25 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, 7.6 m/s at the hub against 6.7 m/s here. Per kW, solar panels would make about 1,498 kWh a year here against the turbine's 2,487, so get a solar quote first.
What would have to change
- Power would have to cost 20¢/kWh, 1.3 times what TX pays now.
- Or the average wind at the hub would have to be 7.6 m/s instead of 6.7. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of TX
Gray County is the 62nd 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 Gray County
April is the strongest month here, at 7.68 m/s and about 2,610 kWh. August is the weakest, 5.74 m/s and 1,511 kWh, so the best month makes 1.7 times the worst. November to March brings in 43% of the year's output in Gray County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.67 m/s | 2,097 kWh | $336 |
| February | 6.84 m/s | 1,984 kWh | $318 |
| March | 7.14 m/s | 2,382 kWh | $382 |
| April | 7.68 m/s | 2,610 kWh | $418 |
| May | 6.88 m/s | 2,224 kWh | $357 |
| June | 6.87 m/s | 2,147 kWh | $344 |
| July | 5.96 m/s | 1,646 kWh | $264 |
| August | 5.74 m/s | 1,511 kWh | $242 |
| September | 6.28 m/s | 1,790 kWh | $287 |
| October | 6.76 m/s | 2,152 kWh | $345 |
| November | 6.95 m/s | 2,195 kWh | $352 |
| December | 6.73 m/s | 2,130 kWh | $341 |
What a taller tower would buy
Measured at 10 m the wind in Gray County averages 5.32 m/s; at 50 m it is 7.46 m/s. That gives a shear exponent of 0.210, typical of ordinary open country. Going from 20 m to 50 m takes output from 20,848 to 30,263 kWh a year, 45% 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 | 6.15 m/s | 20,848 kWh | 30 years |
| 30 m | 6.7 m/s | 24,883 kWh | 25 years |
| 40 m | 7.12 m/s | 27,886 kWh | 22 years |
| 50 m | 7.46 m/s | 30,263 kWh | 21 years |
Counties around Gray County
2 of the 6 closest counties are windier at turbine height; the windiest, Hemphill County, averages 6.76 m/s.
- Roberts County, TX: 6.74 m/s, 25,166 kWh, payback 25 years (30 mi)
- Carson County, TX: 6.7 m/s, 24,874 kWh, payback 25 years (31 mi)
- Donley County, TX: 6.29 m/s, 21,855 kWh, payback 29 years (31 mi)
- Wheeler County, TX: 6.56 m/s, 23,849 kWh, payback 26 years (32 mi)
- Hemphill County, TX: 6.76 m/s, 25,311 kWh, payback 25 years (41 mi)
- Collingsworth County, TX: 6.22 m/s, 21,336 kWh, payback 29 years (43 mi)
Sun versus wind in Gray County
Gray County gets 5.13 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,498 kWh a year; one kW of the turbine above makes 2,487. 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.