Wind Turbine Payback in Box Elder County, UT
Wind turbine payback in Box Elder 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 Box Elder County, UT averages 4.17 m/s (9.3 mph). A 10 kW turbine there would make about 7,461 kWh a year, worth $984 at UT's 13.19¢/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 Box Elder County
A home turbine is not worth buying for savings in Box Elder County unless your spot is far windier than the county average, 8.7 m/s at the hub against 4.17 m/s here. Per kW, solar panels would make about 1,291 kWh a year here against the turbine's 746, so get a solar quote first.
What would have to change
- Power would have to cost 67¢/kWh, 5.1 times what UT pays now.
- Or the average wind at the hub would have to be 8.7 m/s instead of 4.17. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of UT
Box Elder County is the 1,965th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in UT is Daggett County at 5.32 m/s, payback 51 years.
Month by month in Box Elder County
April is the strongest month here, at 4.97 m/s and about 1,011 kWh. January is the weakest, 3.50 m/s and 368 kWh, so the best month makes 2.7 times the worst. November to March brings in 38% of the year's output in Box Elder County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.50 m/s | 368 kWh | $49 |
| February | 4.36 m/s | 656 kWh | $87 |
| March | 4.77 m/s | 938 kWh | $124 |
| April | 4.97 m/s | 1,011 kWh | $133 |
| May | 4.51 m/s | 798 kWh | $105 |
| June | 4.46 m/s | 750 kWh | $99 |
| July | 3.95 m/s | 536 kWh | $71 |
| August | 3.96 m/s | 540 kWh | $71 |
| September | 3.96 m/s | 522 kWh | $69 |
| October | 4.02 m/s | 567 kWh | $75 |
| November | 3.84 m/s | 476 kWh | $63 |
| December | 3.86 m/s | 503 kWh | $66 |
What a taller tower would buy
Measured at 10 m the wind in Box Elder County averages 3.4 m/s; at 50 m it is 4.59 m/s. That gives a shear exponent of 0.186, typical of ordinary open country. Going from 20 m to 50 m takes output from 5,945 to 9,885 kWh a year, 66% 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 | 3.87 m/s | 5,945 kWh | over 100 years |
| 30 m | 4.17 m/s | 7,483 kWh | over 100 years |
| 40 m | 4.4 m/s | 8,768 kWh | 87 years |
| 50 m | 4.59 m/s | 9,885 kWh | 77 years |
Counties around Box Elder County
1 of the 6 closest counties is windier at turbine height; the windiest, Cassia County, averages 4.98 m/s.
- Oneida County, ID: 3.88 m/s, 5,989 kWh, payback over 100 years (48 mi)
- Cassia County, ID: 4.98 m/s, 12,400 kWh, payback 62 years (54 mi)
- Davis County, UT: 3.95 m/s, 6,329 kWh, payback over 100 years (60 mi)
- Weber County, UT: 3.08 m/s, 2,844 kWh, payback over 100 years (66 mi)
- Cache County, UT: 3.08 m/s, 2,844 kWh, payback over 100 years (68 mi)
- Franklin County, ID: 3.67 m/s, 5,034 kWh, payback over 100 years (74 mi)
Sun versus wind in Box Elder County
Box Elder County gets 4.42 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,291 kWh a year; one kW of the turbine above makes 746. Kilowatt for kilowatt, panels make 1.7 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.