Wind Turbine Payback in Covington County, AL
Wind turbine payback in Covington 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 Covington County, AL averages 3.69 m/s (8.3 mph). A 10 kW turbine there would make about 5,121 kWh a year, worth $845 at AL's 16.51¢/kWh. Against an installed cost of about $100,000, that is a payback of over 100 years, and the turbine is built to last about 20.
What to do in Covington County
A home turbine is not worth buying for savings in Covington County unless your spot is far windier than the county average, 7.5 m/s at the hub against 3.69 m/s here. Per kW, solar panels would make about 1,372 kWh a year here against the turbine's 512, so get a solar quote first.
What would have to change
- Power would have to cost 98¢/kWh, 5.9 times what AL pays now.
- Or the average wind at the hub would have to be 7.5 m/s instead of 3.69. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of AL
Covington County is the 2,300th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in AL is Mobile County at 4.72 m/s, payback 57 years.
Month by month in Covington County
March is the strongest month here, at 4.17 m/s and about 635 kWh. July is the weakest, 2.91 m/s and 198 kWh, so the best month makes 3.2 times the worst. November to March brings in 55% of the year's output in Covington County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.12 m/s | 612 kWh | $101 |
| February | 4.14 m/s | 560 kWh | $92 |
| March | 4.17 m/s | 635 kWh | $105 |
| April | 4.01 m/s | 547 kWh | $90 |
| May | 3.54 m/s | 381 kWh | $63 |
| June | 3.05 m/s | 226 kWh | $37 |
| July | 2.91 m/s | 198 kWh | $33 |
| August | 2.96 m/s | 210 kWh | $35 |
| September | 3.54 m/s | 369 kWh | $61 |
| October | 3.82 m/s | 486 kWh | $80 |
| November | 4.03 m/s | 554 kWh | $91 |
| December | 4.02 m/s | 568 kWh | $94 |
What a taller tower would buy
Measured at 10 m the wind in Covington County averages 2.49 m/s; at 50 m it is 4.43 m/s. That gives a shear exponent of 0.358, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 3,202 to 8,924 kWh a year, 179% 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 | 3.19 m/s | 3,202 kWh | over 100 years |
| 30 m | 3.69 m/s | 5,119 kWh | over 100 years |
| 40 m | 4.09 m/s | 7,037 kWh | 86 years |
| 50 m | 4.43 m/s | 8,924 kWh | 68 years |
Counties around Covington County
1 of the 6 closest counties is windier at turbine height; the windiest, Geneva County, averages 4.39 m/s.
- Coffee County, AL: 3.1 m/s, 2,906 kWh, payback over 100 years (29 mi)
- Conecuh County, AL: 2.95 m/s, 2,455 kWh, payback over 100 years (34 mi)
- Crenshaw County, AL: 3.1 m/s, 2,906 kWh, payback over 100 years (34 mi)
- Butler County, AL: 3 m/s, 2,601 kWh, payback over 100 years (38 mi)
- Geneva County, AL: 4.39 m/s, 8,690 kWh, payback 70 years (39 mi)
- Escambia County, AL: 3.47 m/s, 4,211 kWh, payback over 100 years (43 mi)
Sun versus wind in Covington County
Covington County gets 4.7 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,372 kWh a year; one kW of the turbine above makes 512. Kilowatt for kilowatt, panels make 2.7 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.