Wind Turbine Payback in Cook County, GA
Wind turbine payback in Cook 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 Cook County, GA averages 3.98 m/s (8.9 mph). A 10 kW turbine there would make about 6,477 kWh a year, worth $1,003 at GA's 15.48¢/kWh. Against an installed cost of about $100,000, that is a payback of 100 years, and the turbine is built to last about 20.
What to do in Cook County
A home turbine is not worth buying for savings in Cook County unless your spot is far windier than the county average, 7.8 m/s at the hub against 3.98 m/s here. Per kW, solar panels would make about 1,399 kWh a year here against the turbine's 648, so get a solar quote first.
What would have to change
- Power would have to cost 77¢/kWh, 5.0 times what GA pays now.
- Or the average wind at the hub would have to be 7.8 m/s instead of 3.98. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of GA
Cook County is the 2,077th 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 Cook County
March is the strongest month here, at 4.50 m/s and about 794 kWh. July is the weakest, 3.14 m/s and 257 kWh, so the best month makes 3.1 times the worst. November to March brings in 54% of the year's output in Cook County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.43 m/s | 760 kWh | $118 |
| February | 4.44 m/s | 690 kWh | $107 |
| March | 4.50 m/s | 794 kWh | $123 |
| April | 4.32 m/s | 679 kWh | $105 |
| May | 3.88 m/s | 510 kWh | $79 |
| June | 3.32 m/s | 301 kWh | $47 |
| July | 3.14 m/s | 257 kWh | $40 |
| August | 3.16 m/s | 264 kWh | $41 |
| September | 3.78 m/s | 455 kWh | $70 |
| October | 4.09 m/s | 596 kWh | $92 |
| November | 4.32 m/s | 679 kWh | $105 |
| December | 4.32 m/s | 706 kWh | $109 |
What a taller tower would buy
Measured at 10 m the wind in Cook County averages 2.79 m/s; at 50 m it is 4.69 m/s. That gives a shear exponent of 0.323, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 4,283 to 10,508 kWh a year, 145% 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 | 3.49 m/s | 4,283 kWh | over 100 years |
| 30 m | 3.98 m/s | 6,461 kWh | 100 years |
| 40 m | 4.36 m/s | 8,539 kWh | 76 years |
| 50 m | 4.69 m/s | 10,508 kWh | 62 years |
Counties around Cook County
4 of the 6 closest counties are windier at turbine height; the windiest, Tift County, averages 4.84 m/s.
- Berrien County, GA: 4.47 m/s, 9,160 kWh, payback 71 years (15 mi)
- Colquitt County, GA: 4.32 m/s, 8,289 kWh, payback 78 years (20 mi)
- Tift County, GA: 4.84 m/s, 11,472 kWh, payback 56 years (22 mi)
- Lanier County, GA: 3.98 m/s, 6,477 kWh, payback 100 years (23 mi)
- Lowndes County, GA: 3.98 m/s, 6,477 kWh, payback 100 years (24 mi)
- Brooks County, GA: 4.32 m/s, 8,289 kWh, payback 78 years (24 mi)
Sun versus wind in Cook County
Cook County gets 4.79 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,399 kWh a year; one kW of the turbine above makes 648. Kilowatt for kilowatt, panels make 2.2 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.