Wind Turbine Payback in Teton County, MT
Wind turbine payback in Teton 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 Teton County, MT averages 5.4 m/s (12.1 mph). A 10 kW turbine there would make about 15,319 kWh a year, worth $2,165 at MT's 14.13¢/kWh. Against an installed cost of about $100,000, that is a payback of 46 years, and the turbine is built to last about 20.
What to do in Teton County
A home turbine is not worth buying for savings in Teton County unless your spot is far windier than the county average, 8.2 m/s at the hub against 5.4 m/s here. Per kW, solar panels would make about 1,133 kWh a year here against the turbine's 1,532, so get a solar quote first.
What would have to change
- Power would have to cost 33¢/kWh, 2.3 times what MT pays now.
- Or the average wind at the hub would have to be 8.2 m/s instead of 5.4. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MT
Teton County is the 1,283rd 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 Teton County
January is the strongest month here, at 6.70 m/s and about 2,111 kWh. August is the weakest, 4.13 m/s and 615 kWh, so the best month makes 3.4 times the worst. November to March brings in 58% of the year's output in Teton County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.70 m/s | 2,111 kWh | $298 |
| February | 5.90 m/s | 1,457 kWh | $206 |
| March | 5.84 m/s | 1,575 kWh | $223 |
| April | 5.24 m/s | 1,166 kWh | $165 |
| May | 4.74 m/s | 920 kWh | $130 |
| June | 4.65 m/s | 841 kWh | $119 |
| July | 4.30 m/s | 695 kWh | $98 |
| August | 4.13 m/s | 615 kWh | $87 |
| September | 4.64 m/s | 836 kWh | $118 |
| October | 5.70 m/s | 1,484 kWh | $210 |
| November | 6.47 m/s | 1,907 kWh | $269 |
| December | 6.43 m/s | 1,944 kWh | $275 |
What a taller tower would buy
Measured at 10 m the wind in Teton County averages 3.92 m/s; at 50 m it is 6.26 m/s. That gives a shear exponent of 0.291, typical of ordinary open country. Going from 20 m to 50 m takes output from 11,178 to 21,632 kWh a year, 94% 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 | 4.79 m/s | 11,178 kWh | 63 years |
| 30 m | 5.4 m/s | 15,285 kWh | 46 years |
| 40 m | 5.87 m/s | 18,716 kWh | 38 years |
| 50 m | 6.26 m/s | 21,632 kWh | 33 years |
Counties around Teton County
3 of the 6 closest counties are windier at turbine height; the windiest, Toole County, averages 6.17 m/s.
- Pondera County, MT: 5.4 m/s, 15,319 kWh, payback 46 years (28 mi)
- Lewis and Clark County, MT: 3.93 m/s, 6,231 kWh, payback over 100 years (48 mi)
- Cascade County, MT: 5.69 m/s, 17,419 kWh, payback 41 years (56 mi)
- Toole County, MT: 6.17 m/s, 20,965 kWh, payback 34 years (62 mi)
- Glacier County, MT: 5.52 m/s, 16,181 kWh, payback 44 years (69 mi)
- Powell County, MT: 3.35 m/s, 3,757 kWh, payback over 100 years (74 mi)
Sun versus wind in Teton County
Teton County gets 3.88 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,133 kWh a year; one kW of the turbine above makes 1,532. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.4 times. 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.