Wind Turbine Payback in Sagadahoc County, ME
Wind turbine payback in Sagadahoc 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 Sagadahoc County, ME averages 3.65 m/s (8.2 mph). A 10 kW turbine there would make about 4,948 kWh a year, worth $1,496 at ME's 30.23¢/kWh. Against an installed cost of about $100,000, that is a payback of 67 years, and the turbine is built to last about 20.
What to do in Sagadahoc County
A home turbine is not worth buying for savings in Sagadahoc County unless your spot is far windier than the county average, 5.6 m/s at the hub against 3.65 m/s here. Per kW, solar panels would make about 1,113 kWh a year here against the turbine's 495, so get a solar quote first.
What would have to change
- Power would have to cost 101¢/kWh, 3.3 times what ME pays now.
- Or the average wind at the hub would have to be 5.6 m/s instead of 3.65. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of ME
Sagadahoc County is the 2,332nd 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 Sagadahoc County
March is the strongest month here, at 4.49 m/s and about 789 kWh. July is the weakest, 2.79 m/s and 171 kWh, so the best month makes 4.6 times the worst. November to March brings in 61% of the year's output in Sagadahoc County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.27 m/s | 680 kWh | $206 |
| February | 4.52 m/s | 728 kWh | $220 |
| March | 4.49 m/s | 789 kWh | $239 |
| April | 3.98 m/s | 533 kWh | $161 |
| May | 3.29 m/s | 301 kWh | $91 |
| June | 2.97 m/s | 207 kWh | $63 |
| July | 2.79 m/s | 171 kWh | $52 |
| August | 2.88 m/s | 192 kWh | $58 |
| September | 3.16 m/s | 255 kWh | $77 |
| October | 3.68 m/s | 430 kWh | $130 |
| November | 3.83 m/s | 474 kWh | $143 |
| December | 4.00 m/s | 558 kWh | $169 |
What a taller tower would buy
Measured at 10 m the wind in Sagadahoc County averages 2.4 m/s; at 50 m it is 4.44 m/s. That gives a shear exponent of 0.382, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 2,998 to 8,982 kWh a year, 200% 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 | 3.13 m/s | 2,998 kWh | over 100 years |
| 30 m | 3.65 m/s | 4,960 kWh | 67 years |
| 40 m | 4.08 m/s | 6,972 kWh | 47 years |
| 50 m | 4.44 m/s | 8,982 kWh | 37 years |
Counties around Sagadahoc County
2 of the 6 closest counties are windier at turbine height; the windiest, Knox County, averages 6.26 m/s.
- Lincoln County, ME: 4.86 m/s, 11,603 kWh, payback 29 years (17 mi)
- Androscoggin County, ME: 3.65 m/s, 4,948 kWh, payback 67 years (25 mi)
- Cumberland County, ME: 3.5 m/s, 4,329 kWh, payback 76 years (25 mi)
- Kennebec County, ME: 3.51 m/s, 4,368 kWh, payback 76 years (35 mi)
- Knox County, ME: 6.26 m/s, 21,632 kWh, payback 15 years (41 mi)
- Waldo County, ME: 3.48 m/s, 4,250 kWh, payback 78 years (53 mi)
Sun versus wind in Sagadahoc County
Sagadahoc County gets 3.81 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,113 kWh a year; one kW of the turbine above makes 495. 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.