Wind Turbine Payback in Glynn County, GA
Wind turbine payback in Glynn 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 Glynn County, GA averages 5.08 m/s (11.4 mph). A 10 kW turbine there would make about 13,078 kWh a year, worth $2,024 at GA's 15.48¢/kWh. Against an installed cost of about $100,000, that is a payback of 49 years, and the turbine is built to last about 20.
What to do in Glynn County
A home turbine is not worth buying for savings in Glynn County unless your spot is far windier than the county average, 7.8 m/s at the hub against 5.08 m/s here. Per kW, solar panels would make about 1,381 kWh a year here against the turbine's 1,308, so get a solar quote first.
What would have to change
- Power would have to cost 38¢/kWh, 2.5 times what GA pays now.
- Or the average wind at the hub would have to be 7.8 m/s instead of 5.08. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of GA
Glynn County is the 1,418th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. It is the windiest county in GA.
Month by month in Glynn County
January is the strongest month here, at 5.53 m/s and about 1,380 kWh. August is the weakest, 4.24 m/s and 667 kWh, so the best month makes 2.1 times the worst. November to March brings in 49% of the year's output in Glynn County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.53 m/s | 1,380 kWh | $214 |
| February | 5.39 m/s | 1,169 kWh | $181 |
| March | 5.48 m/s | 1,351 kWh | $209 |
| April | 5.47 m/s | 1,302 kWh | $202 |
| May | 5.08 m/s | 1,112 kWh | $172 |
| June | 4.52 m/s | 779 kWh | $121 |
| July | 4.26 m/s | 676 kWh | $105 |
| August | 4.24 m/s | 667 kWh | $103 |
| September | 5.12 m/s | 1,097 kWh | $170 |
| October | 5.17 m/s | 1,161 kWh | $180 |
| November | 5.35 m/s | 1,231 kWh | $191 |
| December | 5.35 m/s | 1,272 kWh | $197 |
What a taller tower would buy
Measured at 10 m the wind in Glynn County averages 4.37 m/s; at 50 m it is 5.45 m/s. That gives a shear exponent of 0.137, typical of very open, smooth ground where height adds little. Going from 20 m to 50 m takes output from 11,257 to 15,677 kWh a year, 39% 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 | 4.81 m/s | 11,257 kWh | 57 years |
| 30 m | 5.08 m/s | 13,089 kWh | 49 years |
| 40 m | 5.29 m/s | 14,509 kWh | 45 years |
| 50 m | 5.45 m/s | 15,677 kWh | 41 years |
Counties around Glynn County
None of the 6 closest counties is windier than Glynn County.
- McIntosh County, GA: 4.38 m/s, 8,632 kWh, payback 75 years (20 mi)
- Camden County, GA: 3.28 m/s, 3,506 kWh, payback over 100 years (22 mi)
- Brantley County, GA: 3.28 m/s, 3,506 kWh, payback over 100 years (29 mi)
- Wayne County, GA: 3.47 m/s, 4,211 kWh, payback over 100 years (34 mi)
- Long County, GA: 3.47 m/s, 4,211 kWh, payback over 100 years (40 mi)
- Liberty County, GA: 3.85 m/s, 5,847 kWh, payback over 100 years (41 mi)
Sun versus wind in Glynn County
Glynn 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 1,308. Kilowatt for kilowatt, panels make 1.1 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.