Wind Turbine Payback in Rabun County, GA
Wind turbine payback in Rabun 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 Rabun County, GA averages 3.05 m/s (6.8 mph). A 10 kW turbine there would make about 2,751 kWh a year, worth $426 at GA's 15.48¢/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 Rabun County
A home turbine is not worth buying for savings in Rabun County unless your spot is far windier than the county average, 7.8 m/s at the hub against 3.05 m/s here. Per kW, solar panels would make about 1,314 kWh a year here against the turbine's 275, so get a solar quote first.
What would have to change
- Power would have to cost 182¢/kWh, 11.7 times what GA pays now.
- Or the average wind at the hub would have to be 7.8 m/s instead of 3.05. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of GA
Rabun County is the 3,024th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in GA is Glynn County at 5.08 m/s, payback 49 years.
Month by month in Rabun County
March is the strongest month here, at 3.61 m/s and about 406 kWh. August is the weakest, 2.25 m/s and 75 kWh, so the best month makes 5.4 times the worst. November to March brings in 58% of the year's output in Rabun County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.53 m/s | 378 kWh | $59 |
| February | 3.61 m/s | 366 kWh | $57 |
| March | 3.61 m/s | 406 kWh | $63 |
| April | 3.57 m/s | 379 kWh | $59 |
| May | 2.99 m/s | 219 kWh | $34 |
| June | 2.55 m/s | 119 kWh | $18 |
| July | 2.34 m/s | 89 kWh | $14 |
| August | 2.25 m/s | 75 kWh | $12 |
| September | 2.68 m/s | 144 kWh | $22 |
| October | 3.03 m/s | 227 kWh | $35 |
| November | 3.19 m/s | 264 kWh | $41 |
| December | 3.27 m/s | 296 kWh | $46 |
What a taller tower would buy
Measured at 10 m the wind in Rabun County averages 1.89 m/s; at 50 m it is 3.81 m/s. That gives a shear exponent of 0.436, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 1,467 to 5,660 kWh a year, 286% 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 | 2.56 m/s | 1,467 kWh | over 100 years |
| 30 m | 3.05 m/s | 2,749 kWh | over 100 years |
| 40 m | 3.46 m/s | 4,159 kWh | over 100 years |
| 50 m | 3.81 m/s | 5,660 kWh | over 100 years |
Counties around Rabun County
3 of the 6 closest counties are windier at turbine height; the windiest, Habersham County, averages 3.12 m/s.
- Habersham County, GA: 3.12 m/s, 2,970 kWh, payback over 100 years (19 mi)
- Towns County, GA: 3.11 m/s, 2,938 kWh, payback over 100 years (19 mi)
- Macon County, NC: 3.05 m/s, 2,751 kWh, payback over 100 years (19 mi)
- Oconee County, SC: 2.95 m/s, 2,455 kWh, payback over 100 years (22 mi)
- Clay County, NC: 3.11 m/s, 2,938 kWh, payback over 100 years (23 mi)
- Stephens County, GA: 2.95 m/s, 2,455 kWh, payback over 100 years (24 mi)
Sun versus wind in Rabun County
Rabun County gets 4.5 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,314 kWh a year; one kW of the turbine above makes 275. Kilowatt for kilowatt, panels make 4.8 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.