Wind Turbine Payback in Alamance County, NC
Wind turbine payback in Alamance 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 Alamance County, NC averages 3.82 m/s (8.5 mph). A 10 kW turbine there would make about 5,707 kWh a year, worth $853 at NC's 14.94¢/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 Alamance County
A home turbine is not worth buying for savings in Alamance County unless your spot is far windier than the county average, 7.9 m/s at the hub against 3.82 m/s here. Per kW, solar panels would make about 1,267 kWh a year here against the turbine's 571, so get a solar quote first.
What would have to change
- Power would have to cost 88¢/kWh, 5.9 times what NC pays now.
- Or the average wind at the hub would have to be 7.9 m/s instead of 3.82. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of NC
Alamance County is the 2,198th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in NC is Dare County at 6.91 m/s, payback 25 years.
Month by month in Alamance County
March is the strongest month here, at 4.51 m/s and about 801 kWh. August is the weakest, 2.89 m/s and 194 kWh, so the best month makes 4.1 times the worst. November to March brings in 55% of the year's output in Alamance County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.33 m/s | 710 kWh | $106 |
| February | 4.48 m/s | 708 kWh | $106 |
| March | 4.51 m/s | 801 kWh | $120 |
| April | 4.49 m/s | 763 kWh | $114 |
| May | 3.78 m/s | 471 kWh | $70 |
| June | 3.28 m/s | 288 kWh | $43 |
| July | 3.01 m/s | 224 kWh | $33 |
| August | 2.89 m/s | 194 kWh | $29 |
| September | 3.39 m/s | 322 kWh | $48 |
| October | 3.76 m/s | 461 kWh | $69 |
| November | 3.98 m/s | 534 kWh | $80 |
| December | 4.08 m/s | 595 kWh | $89 |
What a taller tower would buy
Measured at 10 m the wind in Alamance County averages 2.56 m/s; at 50 m it is 4.61 m/s. That gives a shear exponent of 0.365, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 3,575 to 10,008 kWh a year, 180% 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 | 3.3 m/s | 3,575 kWh | over 100 years |
| 30 m | 3.83 m/s | 5,734 kWh | over 100 years |
| 40 m | 4.25 m/s | 7,894 kWh | 85 years |
| 50 m | 4.61 m/s | 10,008 kWh | 67 years |
Counties around Alamance County
2 of the 6 closest counties are windier at turbine height; the windiest, Guilford County, averages 4.47 m/s.
- Orange County, NC: 3.82 m/s, 5,707 kWh, payback over 100 years (16 mi)
- Guilford County, NC: 4.47 m/s, 9,160 kWh, payback 73 years (22 mi)
- Caswell County, NC: 3.86 m/s, 5,894 kWh, payback over 100 years (24 mi)
- Chatham County, NC: 3.54 m/s, 4,489 kWh, payback over 100 years (25 mi)
- Durham County, NC: 3.47 m/s, 4,211 kWh, payback over 100 years (29 mi)
- Rockingham County, NC: 3.73 m/s, 5,297 kWh, payback over 100 years (32 mi)
Sun versus wind in Alamance County
Alamance County gets 4.34 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,267 kWh a year; one kW of the turbine above makes 571. Kilowatt for kilowatt, panels make 2.2 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.