Wind Turbine Payback in Phelps County, MO
Wind turbine payback in Phelps 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 Phelps County, MO averages 3.41 m/s (7.6 mph). A 10 kW turbine there would make about 3,980 kWh a year, worth $568 at MO's 14.28¢/kWh. Against an installed cost of about $100,000, that is a payback of over 100 years, and the turbine is built to last about 20.
What to do in Phelps County
A home turbine is not worth buying for savings in Phelps County unless your spot is far windier than the county average, 8.2 m/s at the hub against 3.41 m/s here. Per kW, solar panels would make about 1,256 kWh a year here against the turbine's 398, so get a solar quote first.
What would have to change
- Power would have to cost 126¢/kWh, 8.8 times what MO pays now.
- Or the average wind at the hub would have to be 8.2 m/s instead of 3.41. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MO
Phelps County is the 2,607th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in MO is Atchison County at 6.17 m/s, payback 33 years.
Month by month in Phelps County
March is the strongest month here, at 3.97 m/s and about 546 kWh. July is the weakest, 2.65 m/s and 143 kWh, so the best month makes 3.8 times the worst. November to March brings in 56% of the year's output in Phelps County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.87 m/s | 504 kWh | $72 |
| February | 3.95 m/s | 484 kWh | $69 |
| March | 3.97 m/s | 546 kWh | $78 |
| April | 3.93 m/s | 513 kWh | $73 |
| May | 3.32 m/s | 311 kWh | $44 |
| June | 2.96 m/s | 204 kWh | $29 |
| July | 2.65 m/s | 143 kWh | $20 |
| August | 2.68 m/s | 149 kWh | $21 |
| September | 2.93 m/s | 198 kWh | $28 |
| October | 3.41 m/s | 338 kWh | $48 |
| November | 3.64 m/s | 403 kWh | $58 |
| December | 3.67 m/s | 428 kWh | $61 |
What a taller tower would buy
Measured at 10 m the wind in Phelps County averages 2.06 m/s; at 50 m it is 4.31 m/s. That gives a shear exponent of 0.459, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 2,126 to 8,233 kWh a year, 287% 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 | 2.83 m/s | 2,126 kWh | over 100 years |
| 30 m | 3.41 m/s | 3,977 kWh | over 100 years |
| 40 m | 3.89 m/s | 6,039 kWh | over 100 years |
| 50 m | 4.31 m/s | 8,233 kWh | 85 years |
Counties around Phelps County
4 of the 6 closest counties are windier at turbine height; the windiest, Osage County, averages 3.65 m/s.
- Maries County, MO: 3.41 m/s, 3,980 kWh, payback over 100 years (22 mi)
- Pulaski County, MO: 3.55 m/s, 4,530 kWh, payback over 100 years (23 mi)
- Dent County, MO: 3.39 m/s, 3,905 kWh, payback over 100 years (25 mi)
- Crawford County, MO: 3.44 m/s, 4,094 kWh, payback over 100 years (27 mi)
- Texas County, MO: 3.5 m/s, 4,329 kWh, payback over 100 years (39 mi)
- Osage County, MO: 3.65 m/s, 4,948 kWh, payback over 100 years (41 mi)
Sun versus wind in Phelps County
Phelps County gets 4.3 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,256 kWh a year; one kW of the turbine above makes 398. Kilowatt for kilowatt, panels make 3.2 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.