Wind Turbine Payback in Botetourt County, VA
Wind turbine payback in Botetourt 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 Botetourt County, VA averages 3.19 m/s (7.1 mph). A 10 kW turbine there would make about 3,198 kWh a year, worth $542 at VA's 16.95¢/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 Botetourt County
A home turbine is not worth buying for savings in Botetourt County unless your spot is far windier than the county average, 7.3 m/s at the hub against 3.19 m/s here. Per kW, solar panels would make about 1,232 kWh a year here against the turbine's 320, so get a solar quote first.
What would have to change
- Power would have to cost 156¢/kWh, 9.2 times what VA pays now.
- Or the average wind at the hub would have to be 7.3 m/s instead of 3.19. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of VA
Botetourt County is the 2,888th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in VA is Northampton County at 7.01 m/s, payback 22 years.
Month by month in Botetourt County
January is the strongest month here, at 3.93 m/s and about 528 kWh. August is the weakest, 2.31 m/s and 84 kWh, so the best month makes 6.3 times the worst. November to March brings in 63% of the year's output in Botetourt County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.93 m/s | 528 kWh | $89 |
| February | 4.01 m/s | 507 kWh | $86 |
| March | 3.82 m/s | 486 kWh | $82 |
| April | 3.67 m/s | 415 kWh | $70 |
| May | 2.98 m/s | 215 kWh | $36 |
| June | 2.68 m/s | 143 kWh | $24 |
| July | 2.45 m/s | 107 kWh | $18 |
| August | 2.31 m/s | 84 kWh | $14 |
| September | 2.57 m/s | 124 kWh | $21 |
| October | 3.05 m/s | 233 kWh | $39 |
| November | 3.32 m/s | 299 kWh | $51 |
| December | 3.56 m/s | 387 kWh | $66 |
What a taller tower would buy
Measured at 10 m the wind in Botetourt County averages 1.93 m/s; at 50 m it is 4.03 m/s. That gives a shear exponent of 0.457, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 1,682 to 6,729 kWh a year, 300% 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 | 2.65 m/s | 1,682 kWh | over 100 years |
| 30 m | 3.19 m/s | 3,201 kWh | over 100 years |
| 40 m | 3.64 m/s | 4,902 kWh | over 100 years |
| 50 m | 4.03 m/s | 6,729 kWh | 88 years |
Counties around Botetourt County
3 of the 6 closest counties are windier at turbine height; the windiest, Lexington city, averages 3.41 m/s.
- Covington city, VA: 3.37 m/s, 3,830 kWh, payback over 100 years (18 mi)
- Alleghany County, VA: 3.37 m/s, 3,830 kWh, payback over 100 years (19 mi)
- Roanoke city, VA: 3.19 m/s, 3,198 kWh, payback over 100 years (22 mi)
- Bedford County, VA: 3.02 m/s, 2,661 kWh, payback over 100 years (23 mi)
- Salem city, VA: 3.19 m/s, 3,198 kWh, payback over 100 years (24 mi)
- Lexington city, VA: 3.41 m/s, 3,980 kWh, payback over 100 years (24 mi)
Sun versus wind in Botetourt County
Botetourt County gets 4.22 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,232 kWh a year; one kW of the turbine above makes 320. Kilowatt for kilowatt, panels make 3.9 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.