Wind Turbine Payback in Milam County, TX
Wind turbine payback in Milam 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 Milam County, TX averages 5.43 m/s (12.1 mph). A 10 kW turbine there would make about 15,534 kWh a year, worth $2,490 at TX's 16.03¢/kWh. Against an installed cost of about $100,000, that is a payback of 40 years, and the turbine is built to last about 20.
What to do in Milam County
A home turbine is not worth buying for savings in Milam County unless your spot is far windier than the county average, 7.6 m/s at the hub against 5.43 m/s here. Per kW, solar panels would make about 1,384 kWh a year here against the turbine's 1,553, so get a solar quote first.
What would have to change
- Power would have to cost 32¢/kWh, 2.0 times what TX pays now.
- Or the average wind at the hub would have to be 7.6 m/s instead of 5.43. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of TX
Milam County is the 1,252nd 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 Milam County
March is the strongest month here, at 6.14 m/s and about 1,764 kWh. September is the weakest, 4.43 m/s and 734 kWh, so the best month makes 2.4 times the worst. November to March brings in 50% of the year's output in Milam County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.84 m/s | 1,576 kWh | $253 |
| February | 6.06 m/s | 1,548 kWh | $248 |
| March | 6.14 m/s | 1,764 kWh | $283 |
| April | 6.20 m/s | 1,740 kWh | $279 |
| May | 5.67 m/s | 1,466 kWh | $235 |
| June | 5.01 m/s | 1,033 kWh | $166 |
| July | 4.67 m/s | 882 kWh | $141 |
| August | 4.44 m/s | 763 kWh | $122 |
| September | 4.43 m/s | 734 kWh | $118 |
| October | 5.24 m/s | 1,202 kWh | $193 |
| November | 5.70 m/s | 1,439 kWh | $231 |
| December | 5.78 m/s | 1,537 kWh | $246 |
What a taller tower would buy
Measured at 10 m the wind in Milam County averages 4.15 m/s; at 50 m it is 6.15 m/s. That gives a shear exponent of 0.244, typical of ordinary open country. Going from 20 m to 50 m takes output from 11,985 to 20,816 kWh a year, 74% 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 | 4.92 m/s | 11,985 kWh | 52 years |
| 30 m | 5.43 m/s | 15,529 kWh | 40 years |
| 40 m | 5.82 m/s | 18,404 kWh | 34 years |
| 50 m | 6.15 m/s | 20,816 kWh | 30 years |
Counties around Milam County
3 of the 6 closest counties are windier at turbine height; the windiest, Bell County, averages 5.61 m/s.
- Burleson County, TX: 5.41 m/s, 15,390 kWh, payback 41 years (30 mi)
- Falls County, TX: 5.52 m/s, 16,181 kWh, payback 39 years (32 mi)
- Robertson County, TX: 5.27 m/s, 14,397 kWh, payback 43 years (32 mi)
- Lee County, TX: 5.41 m/s, 15,390 kWh, payback 41 years (32 mi)
- Bell County, TX: 5.61 m/s, 16,834 kWh, payback 37 years (34 mi)
- Williamson County, TX: 5.52 m/s, 16,181 kWh, payback 39 years (38 mi)
Sun versus wind in Milam County
Milam County gets 4.74 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,384 kWh a year; one kW of the turbine above makes 1,553. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.1 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.