Wind Turbine Payback in Dougherty County, GA
Wind turbine payback in Dougherty 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 Dougherty County, GA averages 4.66 m/s (10.4 mph). A 10 kW turbine there would make about 10,320 kWh a year, worth $1,597 at GA's 15.48¢/kWh. Against an installed cost of about $100,000, that is a payback of 63 years, and the turbine is built to last about 20.
What to do in Dougherty County
A home turbine is not worth buying for savings in Dougherty County unless your spot is far windier than the county average, 7.8 m/s at the hub against 4.66 m/s here. Per kW, solar panels would make about 1,396 kWh a year here against the turbine's 1,032, so get a solar quote first.
What would have to change
- Power would have to cost 48¢/kWh, 3.1 times what GA pays now.
- Or the average wind at the hub would have to be 7.8 m/s instead of 4.66. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of GA
Dougherty County is the 1,645th 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 Dougherty County
March is the strongest month here, at 5.29 m/s and about 1,235 kWh. July is the weakest, 3.63 m/s and 411 kWh, so the best month makes 3.0 times the worst. November to March brings in 54% of the year's output in Dougherty County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.23 m/s | 1,199 kWh | $186 |
| February | 5.25 m/s | 1,092 kWh | $169 |
| March | 5.29 m/s | 1,235 kWh | $191 |
| April | 5.04 m/s | 1,051 kWh | $163 |
| May | 4.45 m/s | 765 kWh | $118 |
| June | 3.84 m/s | 475 kWh | $74 |
| July | 3.63 m/s | 411 kWh | $64 |
| August | 3.68 m/s | 431 kWh | $67 |
| September | 4.52 m/s | 779 kWh | $121 |
| October | 4.82 m/s | 963 kWh | $149 |
| November | 5.11 m/s | 1,090 kWh | $169 |
| December | 5.13 m/s | 1,142 kWh | $177 |
What a taller tower would buy
Measured at 10 m the wind in Dougherty County averages 3.47 m/s; at 50 m it is 5.35 m/s. That gives a shear exponent of 0.269, typical of ordinary open country. Going from 20 m to 50 m takes output from 7,522 to 14,963 kWh a year, 99% 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 | 4.18 m/s | 7,522 kWh | 86 years |
| 30 m | 4.66 m/s | 10,339 kWh | 63 years |
| 40 m | 5.04 m/s | 12,794 kWh | 51 years |
| 50 m | 5.35 m/s | 14,963 kWh | 43 years |
Counties around Dougherty County
1 of the 6 closest counties is windier at turbine height; the windiest, Worth County, averages 4.84 m/s.
- Lee County, GA: 4.3 m/s, 8,176 kWh, payback 79 years (20 mi)
- Baker County, GA: 4.66 m/s, 10,320 kWh, payback 63 years (21 mi)
- Mitchell County, GA: 3.91 m/s, 6,134 kWh, payback over 100 years (21 mi)
- Worth County, GA: 4.84 m/s, 11,472 kWh, payback 56 years (21 mi)
- Terrell County, GA: 4.3 m/s, 8,176 kWh, payback 79 years (22 mi)
- Calhoun County, GA: 4.66 m/s, 10,320 kWh, payback 63 years (25 mi)
Sun versus wind in Dougherty County
Dougherty County gets 4.78 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,396 kWh a year; one kW of the turbine above makes 1,032. Kilowatt for kilowatt, panels make 1.4 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.