Wind Turbine Payback in Washington County, VT
Wind turbine payback in Washington 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 Washington County, VT averages 3.55 m/s (7.9 mph). A 10 kW turbine there would make about 4,530 kWh a year, worth $1,084 at VT's 23.93¢/kWh. Against an installed cost of about $100,000, that is a payback of 92 years, and the turbine is built to last about 20.
What to do in Washington County
A home turbine is not worth buying for savings in Washington County unless your spot is far windier than the county average, 6.2 m/s at the hub against 3.55 m/s here. Per kW, solar panels would make about 1,013 kWh a year here against the turbine's 453, so get a solar quote first.
What would have to change
- Power would have to cost 110¢/kWh, 4.6 times what VT pays now.
- Or the average wind at the hub would have to be 6.2 m/s instead of 3.55. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of VT
Washington County is the 2,459th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in VT is Franklin County at 3.97 m/s, payback 65 years.
Month by month in Washington County
March is the strongest month here, at 4.27 m/s and about 678 kWh. August is the weakest, 2.84 m/s and 183 kWh, so the best month makes 3.7 times the worst. November to March brings in 58% of the year's output in Washington County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.09 m/s | 600 kWh | $144 |
| February | 4.35 m/s | 647 kWh | $155 |
| March | 4.27 m/s | 678 kWh | $162 |
| April | 4.00 m/s | 543 kWh | $130 |
| May | 3.36 m/s | 323 kWh | $77 |
| June | 3.02 m/s | 219 kWh | $52 |
| July | 2.85 m/s | 185 kWh | $44 |
| August | 2.84 m/s | 183 kWh | $44 |
| September | 3.04 m/s | 223 kWh | $53 |
| October | 3.40 m/s | 336 kWh | $80 |
| November | 3.65 m/s | 405 kWh | $97 |
| December | 3.82 m/s | 484 kWh | $116 |
What a taller tower would buy
Measured at 10 m the wind in Washington County averages 2.28 m/s; at 50 m it is 4.36 m/s. That gives a shear exponent of 0.403, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 2,642 to 8,517 kWh a year, 222% 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 | 3.01 m/s | 2,642 kWh | over 100 years |
| 30 m | 3.55 m/s | 4,525 kWh | 92 years |
| 40 m | 3.99 m/s | 6,502 kWh | 64 years |
| 50 m | 4.36 m/s | 8,517 kWh | 49 years |
Counties around Washington County
3 of the 6 closest counties are windier at turbine height; the windiest, Chittenden County, averages 3.82 m/s.
- Orange County, VT: 3.55 m/s, 4,530 kWh, payback 92 years (22 mi)
- Lamoille County, VT: 3.55 m/s, 4,530 kWh, payback 92 years (23 mi)
- Chittenden County, VT: 3.82 m/s, 5,707 kWh, payback 73 years (26 mi)
- Caledonia County, VT: 3.6 m/s, 4,736 kWh, payback 88 years (28 mi)
- Addison County, VT: 3.43 m/s, 4,056 kWh, payback over 100 years (31 mi)
- Orleans County, VT: 3.77 m/s, 5,477 kWh, payback 76 years (42 mi)
Sun versus wind in Washington County
Washington County gets 3.47 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,013 kWh a year; one kW of the turbine above makes 453. Kilowatt for kilowatt, panels make 2.2 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.