Wind Turbine Payback in Clarke County, GA
Wind turbine payback in Clarke 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 Clarke County, GA averages 2.95 m/s (6.6 mph). A 10 kW turbine there would make about 2,455 kWh a year, worth $380 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 Clarke County
A home turbine is not worth buying for savings in Clarke County unless your spot is far windier than the county average, 7.8 m/s at the hub against 2.95 m/s here. Per kW, solar panels would make about 1,332 kWh a year here against the turbine's 246, so get a solar quote first.
What would have to change
- Power would have to cost 204¢/kWh, 13.2 times what GA pays now.
- Or the average wind at the hub would have to be 7.8 m/s instead of 2.95. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of GA
Clarke County is the 3,083rd 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 Clarke County
March is the strongest month here, at 3.43 m/s and about 345 kWh. August is the weakest, 2.30 m/s and 82 kWh, so the best month makes 4.2 times the worst. November to March brings in 55% of the year's output in Clarke County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.31 m/s | 306 kWh | $47 |
| February | 3.35 m/s | 287 kWh | $44 |
| March | 3.43 m/s | 345 kWh | $53 |
| April | 3.38 m/s | 319 kWh | $49 |
| May | 2.93 m/s | 204 kWh | $32 |
| June | 2.53 m/s | 117 kWh | $18 |
| July | 2.37 m/s | 93 kWh | $14 |
| August | 2.30 m/s | 82 kWh | $13 |
| September | 2.73 m/s | 153 kWh | $24 |
| October | 2.94 m/s | 206 kWh | $32 |
| November | 3.10 m/s | 238 kWh | $37 |
| December | 3.13 m/s | 256 kWh | $40 |
What a taller tower would buy
Measured at 10 m the wind in Clarke County averages 1.74 m/s; at 50 m it is 3.78 m/s. That gives a shear exponent of 0.482, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 1,211 to 5,523 kWh a year, 356% 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 | 2.43 m/s | 1,211 kWh | over 100 years |
| 30 m | 2.96 m/s | 2,470 kWh | over 100 years |
| 40 m | 3.39 m/s | 3,922 kWh | over 100 years |
| 50 m | 3.78 m/s | 5,523 kWh | over 100 years |
Counties around Clarke County
4 of the 6 closest counties are windier at turbine height; the windiest, Oconee County, averages 3.32 m/s.
- Oconee County, GA: 3.32 m/s, 3,648 kWh, payback over 100 years (9 mi)
- Madison County, GA: 2.95 m/s, 2,455 kWh, payback over 100 years (15 mi)
- Jackson County, GA: 3.32 m/s, 3,648 kWh, payback over 100 years (17 mi)
- Oglethorpe County, GA: 2.95 m/s, 2,455 kWh, payback over 100 years (18 mi)
- Barrow County, GA: 3.32 m/s, 3,648 kWh, payback over 100 years (20 mi)
- Walton County, GA: 3.32 m/s, 3,648 kWh, payback over 100 years (24 mi)
Sun versus wind in Clarke County
Clarke County gets 4.56 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,332 kWh a year; one kW of the turbine above makes 246. Kilowatt for kilowatt, panels make 5.4 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.