Wind Turbine Payback in Evans County, GA
Wind turbine payback in Evans 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 Evans County, GA averages 3.96 m/s (8.9 mph). A 10 kW turbine there would make about 6,378 kWh a year, worth $987 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 Evans County
A home turbine is not worth buying for savings in Evans County unless your spot is far windier than the county average, 7.8 m/s at the hub against 3.96 m/s here. Per kW, solar panels would make about 1,369 kWh a year here against the turbine's 638, so get a solar quote first.
What would have to change
- Power would have to cost 78¢/kWh, 5.1 times what GA pays now.
- Or the average wind at the hub would have to be 7.8 m/s instead of 3.96. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of GA
Evans County is the 2,085th 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 Evans County
March is the strongest month here, at 4.50 m/s and about 794 kWh. August is the weakest, 3.17 m/s and 267 kWh, so the best month makes 3.0 times the worst. November to March brings in 52% of the year's output in Evans County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.33 m/s | 710 kWh | $110 |
| February | 4.35 m/s | 649 kWh | $100 |
| March | 4.50 m/s | 794 kWh | $123 |
| April | 4.39 m/s | 715 kWh | $111 |
| May | 4.01 m/s | 564 kWh | $87 |
| June | 3.47 m/s | 345 kWh | $53 |
| July | 3.30 m/s | 303 kWh | $47 |
| August | 3.17 m/s | 267 kWh | $41 |
| September | 3.75 m/s | 444 kWh | $69 |
| October | 3.95 m/s | 539 kWh | $83 |
| November | 4.13 m/s | 596 kWh | $92 |
| December | 4.16 m/s | 628 kWh | $97 |
What a taller tower would buy
Measured at 10 m the wind in Evans County averages 2.73 m/s; at 50 m it is 4.7 m/s. That gives a shear exponent of 0.338, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 4,126 to 10,571 kWh a year, 156% 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 | 3.45 m/s | 4,126 kWh | over 100 years |
| 30 m | 3.95 m/s | 6,352 kWh | over 100 years |
| 40 m | 4.36 m/s | 8,509 kWh | 76 years |
| 50 m | 4.7 m/s | 10,571 kWh | 61 years |
Counties around Evans County
3 of the 6 closest counties are windier at turbine height; the windiest, Bulloch County, averages 4.67 m/s.
- Tattnall County, GA: 3.96 m/s, 6,378 kWh, payback over 100 years (12 mi)
- Bulloch County, GA: 4.67 m/s, 10,382 kWh, payback 62 years (19 mi)
- Candler County, GA: 4.67 m/s, 10,382 kWh, payback 62 years (20 mi)
- Toombs County, GA: 4.56 m/s, 9,702 kWh, payback 67 years (26 mi)
- Bryan County, GA: 3.85 m/s, 5,847 kWh, payback over 100 years (28 mi)
- Long County, GA: 3.47 m/s, 4,211 kWh, payback over 100 years (29 mi)
Sun versus wind in Evans County
Evans County gets 4.69 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,369 kWh a year; one kW of the turbine above makes 638. Kilowatt for kilowatt, panels make 2.1 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.