Wind Turbine Payback in Twin Falls County, ID
Wind turbine payback in Twin Falls 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 Twin Falls County, ID averages 5.3 m/s (11.9 mph). A 10 kW turbine there would make about 14,608 kWh a year, worth $1,902 at ID's 13.02¢/kWh. Against an installed cost of about $100,000, that is a payback of 53 years, and the turbine is built to last about 20.
What to do in Twin Falls County
A home turbine is not worth buying for savings in Twin Falls County unless your spot is far windier than the county average, 8.7 m/s at the hub against 5.3 m/s here. Per kW, solar panels would make about 1,352 kWh a year here against the turbine's 1,461, so get a solar quote first.
What would have to change
- Power would have to cost 34¢/kWh, 2.6 times what ID pays now.
- Or the average wind at the hub would have to be 8.7 m/s instead of 5.3. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of ID
Twin Falls County is the 1,324th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in ID is Owyhee County at 5.38 m/s, payback 51 years.
Month by month in Twin Falls County
March is the strongest month here, at 5.94 m/s and about 1,635 kWh. August is the weakest, 4.47 m/s and 780 kWh, so the best month makes 2.1 times the worst. November to March brings in 50% of the year's output in Twin Falls County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.67 m/s | 1,469 kWh | $191 |
| February | 5.84 m/s | 1,422 kWh | $185 |
| March | 5.94 m/s | 1,635 kWh | $213 |
| April | 5.68 m/s | 1,427 kWh | $186 |
| May | 5.05 m/s | 1,094 kWh | $142 |
| June | 4.98 m/s | 1,019 kWh | $133 |
| July | 4.50 m/s | 794 kWh | $103 |
| August | 4.47 m/s | 780 kWh | $102 |
| September | 4.79 m/s | 914 kWh | $119 |
| October | 5.36 m/s | 1,278 kWh | $166 |
| November | 5.66 m/s | 1,416 kWh | $184 |
| December | 5.71 m/s | 1,491 kWh | $194 |
What a taller tower would buy
Measured at 10 m the wind in Twin Falls County averages 4.1 m/s; at 50 m it is 5.97 m/s. That gives a shear exponent of 0.233, typical of ordinary open country. Going from 20 m to 50 m takes output from 11,356 to 19,482 kWh a year, 72% 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 | 4.82 m/s | 11,356 kWh | 68 years |
| 30 m | 5.3 m/s | 14,609 kWh | 53 years |
| 40 m | 5.67 m/s | 17,254 kWh | 45 years |
| 50 m | 5.97 m/s | 19,482 kWh | 39 years |
Counties around Twin Falls County
1 of the 6 closest counties is windier at turbine height; the windiest, Owyhee County, averages 5.38 m/s.
- Jerome County, ID: 5.3 m/s, 14,608 kWh, payback 53 years (31 mi)
- Gooding County, ID: 4.99 m/s, 12,467 kWh, payback 62 years (44 mi)
- Lincoln County, ID: 4.97 m/s, 12,333 kWh, payback 62 years (51 mi)
- Cassia County, ID: 4.98 m/s, 12,400 kWh, payback 62 years (53 mi)
- Minidoka County, ID: 4.93 m/s, 12,065 kWh, payback 64 years (63 mi)
- Owyhee County, ID: 5.38 m/s, 15,176 kWh, payback 51 years (79 mi)
Sun versus wind in Twin Falls County
Twin Falls County gets 4.63 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,352 kWh a year; one kW of the turbine above makes 1,461. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.1 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.