Wind Turbine Payback in Powell County, MT
Wind turbine payback in Powell 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 Powell County, MT averages 3.35 m/s (7.5 mph). A 10 kW turbine there would make about 3,757 kWh a year, worth $531 at MT's 14.13¢/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 Powell County
A home turbine is not worth buying for savings in Powell County unless your spot is far windier than the county average, 8.2 m/s at the hub against 3.35 m/s here. Per kW, solar panels would make about 1,171 kWh a year here against the turbine's 376, so get a solar quote first.
What would have to change
- Power would have to cost 133¢/kWh, 9.4 times what MT pays now.
- Or the average wind at the hub would have to be 8.2 m/s instead of 3.35. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MT
Powell County is the 2,683rd windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in MT is Fallon County at 6.64 m/s, payback 29 years.
Month by month in Powell County
January is the strongest month here, at 3.63 m/s and about 414 kWh. August is the weakest, 2.87 m/s and 190 kWh, so the best month makes 2.2 times the worst. November to March brings in 50% of the year's output in Powell County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.63 m/s | 414 kWh | $58 |
| February | 3.49 m/s | 329 kWh | $46 |
| March | 3.61 m/s | 405 kWh | $57 |
| April | 3.49 m/s | 353 kWh | $50 |
| May | 3.17 m/s | 266 kWh | $38 |
| June | 3.17 m/s | 257 kWh | $36 |
| July | 2.99 m/s | 218 kWh | $31 |
| August | 2.87 m/s | 190 kWh | $27 |
| September | 3.10 m/s | 240 kWh | $34 |
| October | 3.51 m/s | 370 kWh | $52 |
| November | 3.63 m/s | 400 kWh | $57 |
| December | 3.55 m/s | 384 kWh | $54 |
What a taller tower would buy
Measured at 10 m the wind in Powell County averages 2.23 m/s; at 50 m it is 4.05 m/s. That gives a shear exponent of 0.371, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 2,267 to 6,831 kWh a year, 201% 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 | 2.88 m/s | 2,267 kWh | over 100 years |
| 30 m | 3.35 m/s | 3,760 kWh | over 100 years |
| 40 m | 3.73 m/s | 5,289 kWh | over 100 years |
| 50 m | 4.05 m/s | 6,831 kWh | over 100 years |
Counties around Powell County
5 of the 6 closest counties are windier at turbine height; the windiest, Jefferson County, averages 4.03 m/s.
- Lewis and Clark County, MT: 3.93 m/s, 6,231 kWh, payback over 100 years (32 mi)
- Granite County, MT: 3.77 m/s, 5,477 kWh, payback over 100 years (39 mi)
- Missoula County, MT: 2.8 m/s, 2,047 kWh, payback over 100 years (47 mi)
- Deer Lodge County, MT: 3.65 m/s, 4,948 kWh, payback over 100 years (53 mi)
- Jefferson County, MT: 4.03 m/s, 6,729 kWh, payback over 100 years (65 mi)
- Silver Bow County, MT: 3.78 m/s, 5,523 kWh, payback over 100 years (67 mi)
Sun versus wind in Powell County
Powell County gets 4.01 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,171 kWh a year; one kW of the turbine above makes 376. Kilowatt for kilowatt, panels make 3.1 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.