Wind Turbine Payback in Franklin County, ME
Wind turbine payback in Franklin 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 Franklin County, ME averages 3.87 m/s (8.7 mph). A 10 kW turbine there would make about 5,942 kWh a year, worth $1,796 at ME's 30.23¢/kWh. Against an installed cost of about $100,000, that is a payback of 56 years, and the turbine is built to last about 20.
What to do in Franklin County
A home turbine is not worth buying for savings in Franklin County unless your spot is far windier than the county average, 5.6 m/s at the hub against 3.87 m/s here. Per kW, solar panels would make about 1,063 kWh a year here against the turbine's 594, so get a solar quote first.
What would have to change
- Power would have to cost 84¢/kWh, 2.8 times what ME pays now.
- Or the average wind at the hub would have to be 5.6 m/s instead of 3.87. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of ME
Franklin County is the 2,157th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in ME is Knox County at 6.26 m/s, payback 15 years.
Month by month in Franklin County
March is the strongest month here, at 4.71 m/s and about 905 kWh. August is the weakest, 3.01 m/s and 223 kWh, so the best month makes 4.1 times the worst. November to March brings in 60% of the year's output in Franklin County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.55 m/s | 818 kWh | $247 |
| February | 4.86 m/s | 891 kWh | $269 |
| March | 4.71 m/s | 905 kWh | $274 |
| April | 4.33 m/s | 688 kWh | $208 |
| May | 3.61 m/s | 405 kWh | $122 |
| June | 3.26 m/s | 283 kWh | $86 |
| July | 3.02 m/s | 227 kWh | $69 |
| August | 3.01 m/s | 223 kWh | $67 |
| September | 3.24 m/s | 276 kWh | $83 |
| October | 3.69 m/s | 435 kWh | $132 |
| November | 3.94 m/s | 516 kWh | $156 |
| December | 4.24 m/s | 664 kWh | $201 |
What a taller tower would buy
Measured at 10 m the wind in Franklin County averages 2.55 m/s; at 50 m it is 4.69 m/s. That gives a shear exponent of 0.379, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 3,627 to 10,508 kWh a year, 190% 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 | 3.31 m/s | 3,627 kWh | 91 years |
| 30 m | 3.86 m/s | 5,916 kWh | 56 years |
| 40 m | 4.31 m/s | 8,231 kWh | 40 years |
| 50 m | 4.69 m/s | 10,508 kWh | 32 years |
Counties around Franklin County
1 of the 6 closest counties is windier at turbine height; the windiest, Somerset County, averages 3.92 m/s.
- Oxford County, ME: 3.52 m/s, 4,408 kWh, payback 75 years (37 mi)
- Somerset County, ME: 3.92 m/s, 6,182 kWh, payback 54 years (43 mi)
- Coos County, NH: 3.54 m/s, 4,489 kWh, payback 83 years (48 mi)
- Kennebec County, ME: 3.51 m/s, 4,368 kWh, payback 76 years (50 mi)
- Androscoggin County, ME: 3.65 m/s, 4,948 kWh, payback 67 years (57 mi)
- Essex County, VT: 3.6 m/s, 4,736 kWh, payback 88 years (67 mi)
Sun versus wind in Franklin County
Franklin County gets 3.64 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,063 kWh a year; one kW of the turbine above makes 594. Kilowatt for kilowatt, panels make 1.8 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.