Wind Turbine Payback in Franklin County, PA
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, PA averages 3.99 m/s (8.9 mph). A 10 kW turbine there would make about 6,527 kWh a year, worth $1,379 at PA's 21.13¢/kWh. Against an installed cost of about $100,000, that is a payback of 73 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, 6.5 m/s at the hub against 3.99 m/s here. Per kW, solar panels would make about 1,162 kWh a year here against the turbine's 653, so get a solar quote first.
What would have to change
- Power would have to cost 77¢/kWh, 3.6 times what PA pays now.
- Or the average wind at the hub would have to be 6.5 m/s instead of 3.99. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of PA
Franklin County is the 2,064th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in PA is Philadelphia County at 4.74 m/s, payback 44 years.
Month by month in Franklin County
January is the strongest month here, at 4.75 m/s and about 924 kWh. August is the weakest, 3.03 m/s and 227 kWh, so the best month makes 4.1 times the worst. November to March brings in 59% of the year's output in Franklin County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.75 m/s | 924 kWh | $195 |
| February | 4.85 m/s | 884 kWh | $187 |
| March | 4.75 m/s | 924 kWh | $195 |
| April | 4.50 m/s | 766 kWh | $162 |
| May | 3.74 m/s | 452 kWh | $96 |
| June | 3.40 m/s | 325 kWh | $69 |
| July | 3.12 m/s | 252 kWh | $53 |
| August | 3.03 m/s | 227 kWh | $48 |
| September | 3.37 m/s | 314 kWh | $66 |
| October | 3.88 m/s | 508 kWh | $107 |
| November | 4.18 m/s | 617 kWh | $130 |
| December | 4.40 m/s | 741 kWh | $157 |
What a taller tower would buy
Measured at 10 m the wind in Franklin County averages 2.71 m/s; at 50 m it is 4.77 m/s. That gives a shear exponent of 0.351, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 4,164 to 11,018 kWh a year, 165% 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 | 3.46 m/s | 4,164 kWh | over 100 years |
| 30 m | 3.99 m/s | 6,512 kWh | 73 years |
| 40 m | 4.41 m/s | 8,810 kWh | 54 years |
| 50 m | 4.77 m/s | 11,018 kWh | 43 years |
Counties around Franklin County
1 of the 6 closest counties is windier at turbine height; the windiest, Frederick County, averages 4.56 m/s.
- Fulton County, PA: 3.45 m/s, 4,133 kWh, payback over 100 years (21 mi)
- Washington County, MD: 3.62 m/s, 4,820 kWh, payback 97 years (23 mi)
- Adams County, PA: 3.99 m/s, 6,527 kWh, payback 73 years (27 mi)
- Cumberland County, PA: 3.99 m/s, 6,527 kWh, payback 73 years (29 mi)
- Frederick County, MD: 4.56 m/s, 9,702 kWh, payback 48 years (36 mi)
- Huntingdon County, PA: 3.52 m/s, 4,408 kWh, payback over 100 years (37 mi)
Sun versus wind in Franklin County
Franklin County gets 3.98 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,162 kWh a year; one kW of the turbine above makes 653. 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.