Wind Turbine Payback in Smith County, TX
Wind turbine payback in Smith 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 Smith County, TX averages 4.64 m/s (10.4 mph). A 10 kW turbine there would make about 10,195 kWh a year, worth $1,634 at TX's 16.03¢/kWh. Against an installed cost of about $100,000, that is a payback of 61 years, and the turbine is built to last about 20.
What to do in Smith County
A home turbine is not worth buying for savings in Smith County unless your spot is far windier than the county average, 7.6 m/s at the hub against 4.64 m/s here. Per kW, solar panels would make about 1,358 kWh a year here against the turbine's 1,020, so get a solar quote first.
What would have to change
- Power would have to cost 49¢/kWh, 3.1 times what TX pays now.
- Or the average wind at the hub would have to be 7.6 m/s instead of 4.64. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of TX
Smith County is the 1,667th 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 Smith County
April is the strongest month here, at 5.37 m/s and about 1,240 kWh. August is the weakest, 3.68 m/s and 431 kWh, so the best month makes 2.9 times the worst. November to March brings in 52% of the year's output in Smith County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.09 m/s | 1,117 kWh | $179 |
| February | 5.21 m/s | 1,073 kWh | $172 |
| March | 5.29 m/s | 1,234 kWh | $198 |
| April | 5.37 m/s | 1,240 kWh | $199 |
| May | 4.74 m/s | 918 kWh | $147 |
| June | 4.08 m/s | 576 kWh | $92 |
| July | 3.74 m/s | 453 kWh | $73 |
| August | 3.68 m/s | 431 kWh | $69 |
| September | 4.00 m/s | 539 kWh | $86 |
| October | 4.57 m/s | 827 kWh | $133 |
| November | 4.99 m/s | 1,023 kWh | $164 |
| December | 4.98 m/s | 1,053 kWh | $169 |
What a taller tower would buy
Measured at 10 m the wind in Smith County averages 3.37 m/s; at 50 m it is 5.39 m/s. That gives a shear exponent of 0.292, typical of ordinary open country. Going from 20 m to 50 m takes output from 7,220 to 15,247 kWh a year, 111% 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 | 4.12 m/s | 7,220 kWh | 86 years |
| 30 m | 4.64 m/s | 10,214 kWh | 61 years |
| 40 m | 5.05 m/s | 12,873 kWh | 49 years |
| 50 m | 5.39 m/s | 15,247 kWh | 41 years |
Counties around Smith County
3 of the 6 closest counties are windier at turbine height; the windiest, Wood County, averages 5.53 m/s.
- Gregg County, TX: 4.64 m/s, 10,195 kWh, payback 61 years (27 mi)
- Wood County, TX: 5.53 m/s, 16,254 kWh, payback 38 years (29 mi)
- Upshur County, TX: 4.64 m/s, 10,195 kWh, payback 61 years (31 mi)
- Rusk County, TX: 4.17 m/s, 7,461 kWh, payback 84 years (35 mi)
- Van Zandt County, TX: 5.44 m/s, 15,605 kWh, payback 40 years (35 mi)
- Henderson County, TX: 4.92 m/s, 11,999 kWh, payback 52 years (36 mi)
Sun versus wind in Smith County
Smith 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 1,020. Kilowatt for kilowatt, panels make 1.3 times as much here as the turbine. 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.