Wind Turbine Payback in Brantley County, GA
Wind turbine payback in Brantley 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 Brantley County, GA averages 3.28 m/s (7.3 mph). A 10 kW turbine there would make about 3,506 kWh a year, worth $543 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 Brantley County
A home turbine is not worth buying for savings in Brantley County unless your spot is far windier than the county average, 7.8 m/s at the hub against 3.28 m/s here. Per kW, solar panels would make about 1,381 kWh a year here against the turbine's 351, so get a solar quote first.
What would have to change
- Power would have to cost 143¢/kWh, 9.2 times what GA pays now.
- Or the average wind at the hub would have to be 7.8 m/s instead of 3.28. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of GA
Brantley County is the 2,773rd 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 Brantley County
March is the strongest month here, at 3.66 m/s and about 423 kWh. August is the weakest, 2.72 m/s and 157 kWh, so the best month makes 2.7 times the worst. November to March brings in 51% of the year's output in Brantley County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.54 m/s | 383 kWh | $59 |
| February | 3.57 m/s | 353 kWh | $55 |
| March | 3.66 m/s | 423 kWh | $65 |
| April | 3.61 m/s | 392 kWh | $61 |
| May | 3.30 m/s | 305 kWh | $47 |
| June | 2.86 m/s | 181 kWh | $28 |
| July | 2.72 m/s | 157 kWh | $24 |
| August | 2.72 m/s | 157 kWh | $24 |
| September | 3.19 m/s | 263 kWh | $41 |
| October | 3.34 m/s | 317 kWh | $49 |
| November | 3.46 m/s | 342 kWh | $53 |
| December | 3.45 m/s | 350 kWh | $54 |
What a taller tower would buy
Measured at 10 m the wind in Brantley County averages 2.06 m/s; at 50 m it is 4.07 m/s. That gives a shear exponent of 0.423, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 1,950 to 6,934 kWh a year, 256% 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 | 2.76 m/s | 1,950 kWh | over 100 years |
| 30 m | 3.28 m/s | 3,503 kWh | over 100 years |
| 40 m | 3.7 m/s | 5,179 kWh | over 100 years |
| 50 m | 4.07 m/s | 6,934 kWh | 93 years |
Counties around Brantley County
4 of the 6 closest counties are windier at turbine height; the windiest, Glynn County, averages 5.08 m/s.
- Pierce County, GA: 4.23 m/s, 7,787 kWh, payback 83 years (17 mi)
- Wayne County, GA: 3.47 m/s, 4,211 kWh, payback over 100 years (25 mi)
- Ware County, GA: 3.4 m/s, 3,942 kWh, payback over 100 years (28 mi)
- Camden County, GA: 3.28 m/s, 3,506 kWh, payback over 100 years (28 mi)
- Glynn County, GA: 5.08 m/s, 13,078 kWh, payback 49 years (29 mi)
- Charlton County, GA: 3.28 m/s, 3,506 kWh, payback over 100 years (30 mi)
Sun versus wind in Brantley County
Brantley County gets 4.73 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,381 kWh a year; one kW of the turbine above makes 351. Kilowatt for kilowatt, panels make 3.9 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.