Wind Turbine Payback in Beaufort County, SC
Wind turbine payback in Beaufort 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 Beaufort County, SC averages 5.71 m/s (12.8 mph). A 10 kW turbine there would make about 17,565 kWh a year, worth $2,793 at SC's 15.9¢/kWh. Against an installed cost of about $100,000, that is a payback of 36 years, and the turbine is built to last about 20.
What to do in Beaufort County
A home turbine is not worth buying for savings in Beaufort County unless your spot is far windier than the county average, 7.6 m/s at the hub against 5.71 m/s here. Per kW, solar panels would make about 1,402 kWh a year here against the turbine's 1,757, so get a solar quote first.
What would have to change
- Power would have to cost 28¢/kWh, 1.8 times what SC pays now.
- Or the average wind at the hub would have to be 7.6 m/s instead of 5.71. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of SC
Beaufort County is the 1,125th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. It is the windiest county in SC.
Month by month in Beaufort County
March is the strongest month here, at 6.37 m/s and about 1,908 kWh. August is the weakest, 4.68 m/s and 888 kWh, so the best month makes 2.1 times the worst. November to March brings in 48% of the year's output in Beaufort County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.18 m/s | 1,784 kWh | $284 |
| February | 6.19 m/s | 1,622 kWh | $258 |
| March | 6.37 m/s | 1,908 kWh | $303 |
| April | 6.38 m/s | 1,852 kWh | $294 |
| May | 5.84 m/s | 1,573 kWh | $250 |
| June | 5.18 m/s | 1,129 kWh | $180 |
| July | 4.96 m/s | 1,042 kWh | $166 |
| August | 4.68 m/s | 888 kWh | $141 |
| September | 5.43 m/s | 1,276 kWh | $203 |
| October | 5.50 m/s | 1,364 kWh | $217 |
| November | 5.86 m/s | 1,533 kWh | $244 |
| December | 5.94 m/s | 1,637 kWh | $260 |
What a taller tower would buy
Measured at 10 m the wind in Beaufort County averages 4.93 m/s; at 50 m it is 6.11 m/s. That gives a shear exponent of 0.133, typical of very open, smooth ground where height adds little. Going from 20 m to 50 m takes output from 15,383 to 20,520 kWh a year, 33% 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 | 5.41 m/s | 15,383 kWh | 41 years |
| 30 m | 5.71 m/s | 17,555 kWh | 36 years |
| 40 m | 5.93 m/s | 19,196 kWh | 33 years |
| 50 m | 6.11 m/s | 20,520 kWh | 31 years |
Counties around Beaufort County
None of the 6 closest counties is windier than Beaufort County.
- Jasper County, SC: 3.48 m/s, 4,250 kWh, payback over 100 years (20 mi)
- Colleton County, SC: 4.05 m/s, 6,831 kWh, payback 92 years (34 mi)
- Chatham County, GA: 3.85 m/s, 5,847 kWh, payback over 100 years (35 mi)
- Effingham County, GA: 3.48 m/s, 4,250 kWh, payback over 100 years (38 mi)
- Hampton County, SC: 4.02 m/s, 6,678 kWh, payback 94 years (39 mi)
- Bryan County, GA: 3.85 m/s, 5,847 kWh, payback over 100 years (50 mi)
Sun versus wind in Beaufort County
Beaufort County gets 4.8 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,402 kWh a year; one kW of the turbine above makes 1,757. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.3 times. 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.