Wind Turbine Payback in Brooks County, TX
Wind turbine payback in Brooks 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 Brooks County, TX averages 5.96 m/s (13.3 mph). A 10 kW turbine there would make about 19,408 kWh a year, worth $3,111 at TX's 16.03¢/kWh. Against an installed cost of about $100,000, that is a payback of 32 years, and the turbine is built to last about 20.
What to do in Brooks County
A home turbine is not worth buying for savings in Brooks County unless your spot is far windier than the county average, 7.6 m/s at the hub against 5.96 m/s here. Per kW, solar panels would make about 1,454 kWh a year here against the turbine's 1,941, so get a solar quote first.
What would have to change
- Power would have to cost 26¢/kWh, 1.6 times what TX pays now.
- Or the average wind at the hub would have to be 7.6 m/s instead of 5.96. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of TX
Brooks County is the 901st 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 Brooks County
April is the strongest month here, at 6.77 m/s and about 2,089 kWh. September is the weakest, 5.02 m/s and 1,041 kWh, so the best month makes 2.0 times the worst. November to March brings in 42% of the year's output in Brooks County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.93 m/s | 1,629 kWh | $261 |
| February | 6.17 m/s | 1,609 kWh | $258 |
| March | 6.50 m/s | 1,985 kWh | $318 |
| April | 6.77 m/s | 2,089 kWh | $335 |
| May | 6.63 m/s | 2,069 kWh | $332 |
| June | 6.05 m/s | 1,653 kWh | $265 |
| July | 6.03 m/s | 1,691 kWh | $271 |
| August | 5.40 m/s | 1,300 kWh | $208 |
| September | 5.02 m/s | 1,041 kWh | $167 |
| October | 5.52 m/s | 1,377 kWh | $221 |
| November | 5.75 m/s | 1,467 kWh | $235 |
| December | 5.78 m/s | 1,538 kWh | $247 |
What a taller tower would buy
Measured at 10 m the wind in Brooks County averages 4.75 m/s; at 50 m it is 6.63 m/s. That gives a shear exponent of 0.207, typical of ordinary open country. Going from 20 m to 50 m takes output from 15,925 to 24,362 kWh a year, 53% 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 | 5.48 m/s | 15,925 kWh | 39 years |
| 30 m | 5.96 m/s | 19,443 kWh | 32 years |
| 40 m | 6.33 m/s | 22,156 kWh | 28 years |
| 50 m | 6.63 m/s | 24,362 kWh | 26 years |
Counties around Brooks County
6 of the 6 closest counties are windier at turbine height; the windiest, Kenedy County, averages 6.4 m/s.
- Jim Hogg County, TX: 6.03 m/s, 19,926 kWh, payback 31 years (33 mi)
- Kenedy County, TX: 6.4 m/s, 22,669 kWh, payback 28 years (40 mi)
- Kleberg County, TX: 6.18 m/s, 21,039 kWh, payback 30 years (44 mi)
- Hidalgo County, TX: 6.05 m/s, 20,075 kWh, payback 31 years (44 mi)
- Starr County, TX: 6.05 m/s, 20,075 kWh, payback 31 years (48 mi)
- Duval County, TX: 5.98 m/s, 19,556 kWh, payback 32 years (48 mi)
Sun versus wind in Brooks County
Brooks 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 1,941. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.3 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.