Wind Turbine Payback in Davie County, NC
Wind turbine payback in Davie 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 Davie County, NC averages 4.41 m/s (9.9 mph). A 10 kW turbine there would make about 8,807 kWh a year, worth $1,316 at NC's 14.94¢/kWh. Against an installed cost of about $100,000, that is a payback of 76 years, and the turbine is built to last about 20.
What to do in Davie County
A home turbine is not worth buying for savings in Davie County unless your spot is far windier than the county average, 7.9 m/s at the hub against 4.41 m/s here. Per kW, solar panels would make about 1,305 kWh a year here against the turbine's 881, so get a solar quote first.
What would have to change
- Power would have to cost 57¢/kWh, 3.8 times what NC pays now.
- Or the average wind at the hub would have to be 7.9 m/s instead of 4.41. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of NC
Davie County is the 1,810th 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 Davie County
March is the strongest month here, at 5.24 m/s and about 1,205 kWh. August is the weakest, 3.27 m/s and 294 kWh, so the best month makes 4.1 times the worst. November to March brings in 53% of the year's output in Davie County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.89 m/s | 1,000 kWh | $149 |
| February | 5.12 m/s | 1,024 kWh | $153 |
| March | 5.24 m/s | 1,205 kWh | $180 |
| April | 5.30 m/s | 1,202 kWh | $180 |
| May | 4.41 m/s | 748 kWh | $112 |
| June | 3.76 m/s | 446 kWh | $67 |
| July | 3.40 m/s | 333 kWh | $50 |
| August | 3.27 m/s | 294 kWh | $44 |
| September | 3.96 m/s | 524 kWh | $78 |
| October | 4.41 m/s | 748 kWh | $112 |
| November | 4.58 m/s | 809 kWh | $121 |
| December | 4.60 m/s | 845 kWh | $126 |
What a taller tower would buy
Measured at 10 m the wind in Davie County averages 3.24 m/s; at 50 m it is 5.09 m/s. That gives a shear exponent of 0.281, typical of ordinary open country. Going from 20 m to 50 m takes output from 6,253 to 13,146 kWh a year, 110% 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 | 3.93 m/s | 6,253 kWh | over 100 years |
| 30 m | 4.41 m/s | 8,803 kWh | 76 years |
| 40 m | 4.78 m/s | 11,086 kWh | 60 years |
| 50 m | 5.09 m/s | 13,146 kWh | 51 years |
Counties around Davie County
2 of the 6 closest counties are windier at turbine height; the windiest, Davidson County, averages 4.47 m/s.
- Yadkin County, NC: 4.41 m/s, 8,807 kWh, payback 76 years (17 mi)
- Rowan County, NC: 4.41 m/s, 8,807 kWh, payback 76 years (20 mi)
- Iredell County, NC: 4.41 m/s, 8,807 kWh, payback 76 years (20 mi)
- Davidson County, NC: 4.47 m/s, 9,160 kWh, payback 73 years (21 mi)
- Forsyth County, NC: 4.47 m/s, 9,160 kWh, payback 73 years (21 mi)
- Surry County, NC: 3.78 m/s, 5,523 kWh, payback over 100 years (35 mi)
Sun versus wind in Davie County
Davie County gets 4.47 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,305 kWh a year; one kW of the turbine above makes 881. Kilowatt for kilowatt, panels make 1.5 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.