Wind Turbine Payback in Brazoria County, TX
Wind turbine payback in Brazoria 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 Brazoria County, TX averages 5.56 m/s (12.4 mph). A 10 kW turbine there would make about 16,471 kWh a year, worth $2,640 at TX's 16.03¢/kWh. Against an installed cost of about $100,000, that is a payback of 38 years, and the turbine is built to last about 20.
What to do in Brazoria County
A home turbine is not worth buying for savings in Brazoria County unless your spot is far windier than the county average, 7.6 m/s at the hub against 5.56 m/s here. Per kW, solar panels would make about 1,358 kWh a year here against the turbine's 1,647, so get a solar quote first.
What would have to change
- Power would have to cost 30¢/kWh, 1.9 times what TX pays now.
- Or the average wind at the hub would have to be 7.6 m/s instead of 5.56. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of TX
Brazoria County is the 1,181st 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 Brazoria County
April is the strongest month here, at 6.29 m/s and about 1,793 kWh. August is the weakest, 4.33 m/s and 706 kWh, so the best month makes 2.5 times the worst. November to March brings in 51% of the year's output in Brazoria County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.14 m/s | 1,763 kWh | $283 |
| February | 6.24 m/s | 1,648 kWh | $264 |
| March | 6.17 m/s | 1,780 kWh | $285 |
| April | 6.29 m/s | 1,793 kWh | $287 |
| May | 5.84 m/s | 1,576 kWh | $253 |
| June | 4.98 m/s | 1,020 kWh | $164 |
| July | 4.56 m/s | 823 kWh | $132 |
| August | 4.33 m/s | 706 kWh | $113 |
| September | 4.84 m/s | 942 kWh | $151 |
| October | 5.42 m/s | 1,315 kWh | $211 |
| November | 5.78 m/s | 1,487 kWh | $238 |
| December | 6.11 m/s | 1,746 kWh | $280 |
What a taller tower would buy
Measured at 10 m the wind in Brazoria County averages 4.42 m/s; at 50 m it is 6.18 m/s. That gives a shear exponent of 0.208, typical of ordinary open country. Going from 20 m to 50 m takes output from 13,267 to 21,039 kWh a year, 59% 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 | 5.11 m/s | 13,267 kWh | 47 years |
| 30 m | 5.56 m/s | 16,450 kWh | 38 years |
| 40 m | 5.9 m/s | 18,962 kWh | 33 years |
| 50 m | 6.18 m/s | 21,039 kWh | 30 years |
Counties around Brazoria County
2 of the 6 closest counties are windier at turbine height; the windiest, Galveston County, averages 6.01 m/s.
- Fort Bend County, TX: 5.16 m/s, 13,629 kWh, payback 46 years (32 mi)
- Galveston County, TX: 6.01 m/s, 19,778 kWh, payback 32 years (33 mi)
- Matagorda County, TX: 5.4 m/s, 15,319 kWh, payback 41 years (44 mi)
- Harris County, TX: 4.53 m/s, 9,519 kWh, payback 66 years (48 mi)
- Wharton County, TX: 5.24 m/s, 14,186 kWh, payback 44 years (49 mi)
- Chambers County, TX: 5.76 m/s, 17,932 kWh, payback 35 years (59 mi)
Sun versus wind in Brazoria County
Brazoria County gets 4.65 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,358 kWh a year; one kW of the turbine above makes 1,647. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.2 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.