Wind Turbine Payback in Accomack County, VA
Wind turbine payback in Accomack 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 Accomack County, VA averages 6.35 m/s (14.2 mph). A 10 kW turbine there would make about 22,299 kWh a year, worth $3,780 at VA's 16.95¢/kWh. Against an installed cost of about $100,000, that is a payback of 27 years, and the turbine is built to last about 20.
What to do in Accomack County
A home turbine is not worth buying for savings in Accomack County unless your spot is far windier than the county average, 7.3 m/s at the hub against 6.35 m/s here. Per kW, solar panels would make about 1,259 kWh a year here against the turbine's 2,230, so get a solar quote first.
What would have to change
- Power would have to cost 22¢/kWh, 1.3 times what VA pays now.
- Or the average wind at the hub would have to be 7.3 m/s instead of 6.35. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of VA
Accomack County is the 402nd 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 Accomack County
January is the strongest month here, at 7.28 m/s and about 2,467 kWh. August is the weakest, 4.84 m/s and 976 kWh, so the best month makes 2.5 times the worst. November to March brings in 52% of the year's output in Accomack County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 7.28 m/s | 2,467 kWh | $418 |
| February | 7.20 m/s | 2,184 kWh | $370 |
| March | 7.23 m/s | 2,435 kWh | $413 |
| April | 7.18 m/s | 2,330 kWh | $395 |
| May | 6.16 m/s | 1,774 kWh | $301 |
| June | 5.53 m/s | 1,338 kWh | $227 |
| July | 5.03 m/s | 1,079 kWh | $183 |
| August | 4.84 m/s | 976 kWh | $165 |
| September | 5.61 m/s | 1,386 kWh | $235 |
| October | 6.34 m/s | 1,888 kWh | $320 |
| November | 6.79 m/s | 2,101 kWh | $356 |
| December | 7.03 m/s | 2,315 kWh | $392 |
What a taller tower would buy
Measured at 10 m the wind in Accomack County averages 5.15 m/s; at 50 m it is 7 m/s. That gives a shear exponent of 0.191, typical of ordinary open country. Going from 20 m to 50 m takes output from 18,788 to 27,043 kWh a year, 44% 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 | 5.88 m/s | 18,788 kWh | 31 years |
| 30 m | 6.35 m/s | 22,294 kWh | 27 years |
| 40 m | 6.71 m/s | 24,932 kWh | 24 years |
| 50 m | 7 m/s | 27,043 kWh | 22 years |
Counties around Accomack County
2 of the 6 closest counties are windier at turbine height; the windiest, Northampton County, averages 7.01 m/s.
- Somerset County, MD: 6.35 m/s, 22,299 kWh, payback 21 years (22 mi)
- Northampton County, VA: 7.01 m/s, 27,114 kWh, payback 22 years (33 mi)
- Northumberland County, VA: 5.43 m/s, 15,534 kWh, payback 38 years (35 mi)
- Lancaster County, VA: 5.5 m/s, 16,037 kWh, payback 37 years (36 mi)
- Mathews County, VA: 5.5 m/s, 16,037 kWh, payback 37 years (37 mi)
- Worcester County, MD: 7.01 m/s, 27,114 kWh, payback 17 years (40 mi)
Sun versus wind in Accomack County
Accomack County gets 4.31 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,259 kWh a year; one kW of the turbine above makes 2,230. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.8 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.