TurbinePayback

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

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.

MonthWind at 30 mOutputWorth
January3.02 m/s225 kWh$32
February2.90 m/s177 kWh$25
March2.95 m/s208 kWh$29
April2.80 m/s168 kWh$24
May2.53 m/s120 kWh$17
June2.44 m/s101 kWh$14
July2.25 m/s75 kWh$11
August2.30 m/s83 kWh$12
September2.48 m/s108 kWh$15
October2.82 m/s179 kWh$25
November3.02 m/s218 kWh$31
December2.98 m/s217 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 heightAverage windOutputPayback
20 m2.35 m/s1,065 kWhover 100 years
30 m2.71 m/s1,813 kWhover 100 years
40 m2.99 m/s2,571 kWhover 100 years
50 m3.23 m/s3,333 kWhover 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.

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.