Wind Turbine Payback in Stephens County, TX
Wind turbine payback in Stephens 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 Stephens County, TX averages 6.13 m/s (13.7 mph). A 10 kW turbine there would make about 20,668 kWh a year, worth $3,313 at TX's 16.03¢/kWh. Against an installed cost of about $100,000, that is a payback of 30 years, and the turbine is built to last about 20.
What to do in Stephens County
A home turbine is not worth buying for savings in Stephens County unless your spot is far windier than the county average, 7.6 m/s at the hub against 6.13 m/s here. Per kW, solar panels would make about 1,454 kWh a year here against the turbine's 2,067, so get a solar quote first.
What would have to change
- Power would have to cost 24¢/kWh, 1.5 times what TX pays now.
- Or the average wind at the hub would have to be 7.6 m/s instead of 6.13. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of TX
Stephens County is the 658th 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 Stephens County
April is the strongest month here, at 7.20 m/s and about 2,338 kWh. August is the weakest, 5.00 m/s and 1,067 kWh, so the best month makes 2.2 times the worst. November to March brings in 47% of the year's output in Stephens County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.34 m/s | 1,888 kWh | $303 |
| February | 6.54 m/s | 1,817 kWh | $291 |
| March | 6.82 m/s | 2,189 kWh | $351 |
| April | 7.20 m/s | 2,338 kWh | $375 |
| May | 6.45 m/s | 1,956 kWh | $314 |
| June | 6.00 m/s | 1,621 kWh | $260 |
| July | 5.32 m/s | 1,250 kWh | $200 |
| August | 5.00 m/s | 1,067 kWh | $171 |
| September | 5.12 m/s | 1,097 kWh | $176 |
| October | 6.04 m/s | 1,697 kWh | $272 |
| November | 6.43 m/s | 1,882 kWh | $302 |
| December | 6.31 m/s | 1,866 kWh | $299 |
What a taller tower would buy
Measured at 10 m the wind in Stephens County averages 4.79 m/s; at 50 m it is 6.87 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 16,727 to 26,109 kWh a year, 56% 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 | 5.6 m/s | 16,727 kWh | 37 years |
| 30 m | 6.13 m/s | 20,647 kWh | 30 years |
| 40 m | 6.54 m/s | 23,665 kWh | 26 years |
| 50 m | 6.87 m/s | 26,109 kWh | 24 years |
Counties around Stephens County
3 of the 6 closest counties are windier at turbine height; the windiest, Shackelford County, averages 6.26 m/s.
- Eastland County, TX: 6.13 m/s, 20,668 kWh, payback 30 years (29 mi)
- Shackelford County, TX: 6.26 m/s, 21,632 kWh, payback 29 years (30 mi)
- Palo Pinto County, TX: 5.94 m/s, 19,260 kWh, payback 32 years (30 mi)
- Young County, TX: 6.07 m/s, 20,223 kWh, payback 31 years (31 mi)
- Throckmorton County, TX: 6.16 m/s, 20,891 kWh, payback 30 years (37 mi)
- Callahan County, TX: 6.26 m/s, 21,632 kWh, payback 29 years (44 mi)
Sun versus wind in Stephens County
Stephens County gets 4.98 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,454 kWh a year; one kW of the turbine above makes 2,067. 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.