Wind Turbine Payback in Ravalli County, MT
Wind turbine payback in Ravalli 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 Ravalli County, MT averages 2.71 m/s (6.1 mph). A 10 kW turbine there would make about 1,821 kWh a year, worth $257 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 Ravalli County
A home turbine is not worth buying for savings in Ravalli County unless your spot is far windier than the county average, 8.2 m/s at the hub against 2.71 m/s here. Per kW, solar panels would make about 1,115 kWh a year here against the turbine's 182, so get a solar quote first.
What would have to change
- Power would have to cost 275¢/kWh, 19.4 times what MT pays now.
- Or the average wind at the hub would have to be 8.2 m/s instead of 2.71. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MT
Ravalli County is the 3,130th 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 Ravalli County
January is the strongest month here, at 3.02 m/s and about 225 kWh. July is the weakest, 2.25 m/s and 75 kWh, so the best month makes 3.0 times the worst. November to March brings in 56% of the year's output in Ravalli County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.02 m/s | 225 kWh | $32 |
| February | 2.90 m/s | 177 kWh | $25 |
| March | 2.95 m/s | 208 kWh | $29 |
| April | 2.80 m/s | 168 kWh | $24 |
| May | 2.53 m/s | 120 kWh | $17 |
| June | 2.44 m/s | 101 kWh | $14 |
| July | 2.25 m/s | 75 kWh | $11 |
| August | 2.30 m/s | 83 kWh | $12 |
| September | 2.48 m/s | 108 kWh | $15 |
| October | 2.82 m/s | 179 kWh | $25 |
| November | 3.02 m/s | 218 kWh | $31 |
| December | 2.98 m/s | 217 kWh | $31 |
What a taller tower would buy
Measured at 10 m the wind in Ravalli County averages 1.85 m/s; at 50 m it is 3.23 m/s. That gives a shear exponent of 0.346, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 1,065 to 3,333 kWh a year, 213% 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 | 2.35 m/s | 1,065 kWh | over 100 years |
| 30 m | 2.71 m/s | 1,813 kWh | over 100 years |
| 40 m | 2.99 m/s | 2,571 kWh | over 100 years |
| 50 m | 3.23 m/s | 3,333 kWh | over 100 years |
Counties around Ravalli County
6 of the 6 closest counties are windier at turbine height; the windiest, Silver Bow County, averages 3.78 m/s.
- Granite County, MT: 3.77 m/s, 5,477 kWh, payback over 100 years (39 mi)
- Deer Lodge County, MT: 3.65 m/s, 4,948 kWh, payback over 100 years (46 mi)
- Missoula County, MT: 2.8 m/s, 2,047 kWh, payback over 100 years (66 mi)
- Idaho County, ID: 2.77 m/s, 1,970 kWh, payback over 100 years (67 mi)
- Silver Bow County, MT: 3.78 m/s, 5,523 kWh, payback over 100 years (71 mi)
- Powell County, MT: 3.35 m/s, 3,757 kWh, payback over 100 years (77 mi)
Sun versus wind in Ravalli County
Ravalli County gets 3.82 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,115 kWh a year; one kW of the turbine above makes 182. Kilowatt for kilowatt, panels make 6.1 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.