Wind Turbine Payback in Beaverhead County, MT
Wind turbine payback in Beaverhead 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 Beaverhead County, MT averages 3.95 m/s (8.8 mph). A 10 kW turbine there would make about 6,329 kWh a year, worth $894 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 Beaverhead County
A home turbine is not worth buying for savings in Beaverhead County unless your spot is far windier than the county average, 8.2 m/s at the hub against 3.95 m/s here. Per kW, solar panels would make about 1,232 kWh a year here against the turbine's 633, so get a solar quote first.
What would have to change
- Power would have to cost 79¢/kWh, 5.6 times what MT pays now.
- Or the average wind at the hub would have to be 8.2 m/s instead of 3.95. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MT
Beaverhead County is the 2,089th 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 Beaverhead County
March is the strongest month here, at 4.48 m/s and about 782 kWh. August is the weakest, 3.23 m/s and 282 kWh, so the best month makes 2.8 times the worst. November to March brings in 56% of the year's output in Beaverhead County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.44 m/s | 765 kWh | $108 |
| February | 4.30 m/s | 629 kWh | $89 |
| March | 4.48 m/s | 782 kWh | $110 |
| April | 4.19 m/s | 622 kWh | $88 |
| May | 3.67 m/s | 426 kWh | $60 |
| June | 3.56 m/s | 376 kWh | $53 |
| July | 3.25 m/s | 290 kWh | $41 |
| August | 3.23 m/s | 282 kWh | $40 |
| September | 3.43 m/s | 333 kWh | $47 |
| October | 4.05 m/s | 580 kWh | $82 |
| November | 4.42 m/s | 727 kWh | $103 |
| December | 4.39 m/s | 739 kWh | $104 |
What a taller tower would buy
Measured at 10 m the wind in Beaverhead County averages 2.96 m/s; at 50 m it is 4.51 m/s. That gives a shear exponent of 0.262, typical of ordinary open country. Going from 20 m to 50 m takes output from 4,519 to 9,399 kWh a year, 108% 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 | 3.55 m/s | 4,519 kWh | over 100 years |
| 30 m | 3.95 m/s | 6,304 kWh | over 100 years |
| 40 m | 4.25 m/s | 7,919 kWh | 89 years |
| 50 m | 4.51 m/s | 9,399 kWh | 75 years |
Counties around Beaverhead County
2 of the 6 closest counties are windier at turbine height; the windiest, Madison County, averages 4.63 m/s.
- Madison County, MT: 4.63 m/s, 10,132 kWh, payback 70 years (49 mi)
- Lemhi County, ID: 3.22 m/s, 3,299 kWh, payback over 100 years (51 mi)
- Silver Bow County, MT: 3.78 m/s, 5,523 kWh, payback over 100 years (54 mi)
- Clark County, ID: 3.94 m/s, 6,280 kWh, payback over 100 years (64 mi)
- Deer Lodge County, MT: 3.65 m/s, 4,948 kWh, payback over 100 years (67 mi)
- Jefferson County, MT: 4.03 m/s, 6,729 kWh, payback over 100 years (79 mi)
Sun versus wind in Beaverhead County
Beaverhead County gets 4.22 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,232 kWh a year; one kW of the turbine above makes 633. Kilowatt for kilowatt, panels make 1.9 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.