Wind Turbine Payback in Edgecombe County, NC
Wind turbine payback in Edgecombe 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 Edgecombe County, NC averages 4.9 m/s (11 mph). A 10 kW turbine there would make about 11,866 kWh a year, worth $1,773 at NC's 14.94¢/kWh. Against an installed cost of about $100,000, that is a payback of 56 years, and the turbine is built to last about 20.
What to do in Edgecombe County
A home turbine is not worth buying for savings in Edgecombe County unless your spot is far windier than the county average, 7.9 m/s at the hub against 4.9 m/s here. Per kW, solar panels would make about 1,305 kWh a year here against the turbine's 1,187, so get a solar quote first.
What would have to change
- Power would have to cost 42¢/kWh, 2.8 times what NC pays now.
- Or the average wind at the hub would have to be 7.9 m/s instead of 4.9. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of NC
Edgecombe County is the 1,502nd 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 Edgecombe County
April is the strongest month here, at 5.71 m/s and about 1,447 kWh. August is the weakest, 3.86 m/s and 500 kWh, so the best month makes 2.9 times the worst. November to March brings in 50% of the year's output in Edgecombe County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.31 m/s | 1,249 kWh | $187 |
| February | 5.52 m/s | 1,243 kWh | $186 |
| March | 5.64 m/s | 1,446 kWh | $216 |
| April | 5.71 m/s | 1,447 kWh | $216 |
| May | 4.97 m/s | 1,045 kWh | $156 |
| June | 4.35 m/s | 694 kWh | $104 |
| July | 4.09 m/s | 600 kWh | $90 |
| August | 3.86 m/s | 500 kWh | $75 |
| September | 4.50 m/s | 770 kWh | $115 |
| October | 4.78 m/s | 943 kWh | $141 |
| November | 5.01 m/s | 1,035 kWh | $155 |
| December | 5.10 m/s | 1,120 kWh | $167 |
What a taller tower would buy
Measured at 10 m the wind in Edgecombe County averages 3.64 m/s; at 50 m it is 5.62 m/s. That gives a shear exponent of 0.270, typical of ordinary open country. Going from 20 m to 50 m takes output from 8,680 to 16,907 kWh a year, 95% 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 | 4.39 m/s | 8,680 kWh | 77 years |
| 30 m | 4.9 m/s | 11,840 kWh | 57 years |
| 40 m | 5.29 m/s | 14,548 kWh | 46 years |
| 50 m | 5.62 m/s | 16,907 kWh | 40 years |
Counties around Edgecombe County
4 of the 6 closest counties are windier at turbine height; the windiest, Wilson County, averages 5.2 m/s.
- Nash County, NC: 4.35 m/s, 8,460 kWh, payback 79 years (22 mi)
- Halifax County, NC: 3.99 m/s, 6,527 kWh, payback over 100 years (23 mi)
- Wilson County, NC: 5.2 m/s, 13,907 kWh, payback 48 years (23 mi)
- Pitt County, NC: 4.94 m/s, 12,132 kWh, payback 55 years (26 mi)
- Martin County, NC: 4.96 m/s, 12,266 kWh, payback 55 years (27 mi)
- Greene County, NC: 4.94 m/s, 12,132 kWh, payback 55 years (30 mi)
Sun versus wind in Edgecombe County
Edgecombe 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 1,187. Kilowatt for kilowatt, panels make 1.1 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.