Wind Turbine Payback in Castro County, TX
Wind turbine payback in Castro 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 Castro County, TX averages 6.39 m/s (14.3 mph). A 10 kW turbine there would make about 22,595 kWh a year, worth $3,622 at TX's 16.03¢/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 Castro County
A home turbine is not worth buying for savings in Castro County unless your spot is far windier than the county average, 7.6 m/s at the hub against 6.39 m/s here. Per kW, solar panels would make about 1,594 kWh a year here against the turbine's 2,260, so get a solar quote first.
What would have to change
- Power would have to cost 22¢/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 6.39. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of TX
Castro County is the 347th 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 Castro County
April is the strongest month here, at 7.30 m/s and about 2,395 kWh. August is the weakest, 5.36 m/s and 1,276 kWh, so the best month makes 1.9 times the worst. November to March brings in 45% of the year's output in Castro County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.47 m/s | 1,969 kWh | $316 |
| February | 6.73 m/s | 1,924 kWh | $308 |
| March | 6.89 m/s | 2,228 kWh | $357 |
| April | 7.30 m/s | 2,395 kWh | $384 |
| May | 6.62 m/s | 2,063 kWh | $331 |
| June | 6.43 m/s | 1,884 kWh | $302 |
| July | 5.58 m/s | 1,412 kWh | $226 |
| August | 5.36 m/s | 1,276 kWh | $205 |
| September | 5.80 m/s | 1,500 kWh | $240 |
| October | 6.36 m/s | 1,902 kWh | $305 |
| November | 6.63 m/s | 2,002 kWh | $321 |
| December | 6.57 m/s | 2,030 kWh | $325 |
What a taller tower would buy
Measured at 10 m the wind in Castro County averages 4.96 m/s; at 50 m it is 7.19 m/s. That gives a shear exponent of 0.231, typical of ordinary open country. Going from 20 m to 50 m takes output from 18,362 to 28,390 kWh a year, 55% 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 | 5.82 m/s | 18,362 kWh | 34 years |
| 30 m | 6.39 m/s | 22,593 kWh | 28 years |
| 40 m | 6.83 m/s | 25,811 kWh | 24 years |
| 50 m | 7.19 m/s | 28,390 kWh | 22 years |
Counties around Castro County
3 of the 6 closest counties are windier at turbine height; the windiest, Deaf Smith County, averages 6.63 m/s.
- Swisher County, TX: 6.48 m/s, 23,260 kWh, payback 27 years (29 mi)
- Parmer County, TX: 6.39 m/s, 22,595 kWh, payback 28 years (30 mi)
- Lamb County, TX: 6.22 m/s, 21,336 kWh, payback 29 years (33 mi)
- Deaf Smith County, TX: 6.63 m/s, 24,362 kWh, payback 26 years (34 mi)
- Randall County, TX: 6.6 m/s, 24,142 kWh, payback 26 years (36 mi)
- Hale County, TX: 6.37 m/s, 22,447 kWh, payback 28 years (41 mi)
Sun versus wind in Castro County
Castro County gets 5.46 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,594 kWh a year; one kW of the turbine above makes 2,260. 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.