Wind Turbine Payback in Faulk County, SD
Wind turbine payback in Faulk 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 Faulk County, SD averages 6.36 m/s (14.2 mph). A 10 kW turbine there would make about 22,373 kWh a year, worth $3,262 at SD's 14.58¢/kWh. Against an installed cost of about $100,000, that is a payback of 31 years, and the turbine is built to last about 20.
What to do in Faulk County
A home turbine is not worth buying for savings in Faulk County unless your spot is far windier than the county average, 8.1 m/s at the hub against 6.36 m/s here. Per kW, solar panels would make about 1,197 kWh a year here against the turbine's 2,237, so get a solar quote first.
What would have to change
- Power would have to cost 22¢/kWh, 1.5 times what SD pays now.
- Or the average wind at the hub would have to be 8.1 m/s instead of 6.36. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of SD
Faulk County is the 393rd windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in SD is Todd County at 6.77 m/s, payback 27 years.
Month by month in Faulk County
October is the strongest month here, at 6.85 m/s and about 2,207 kWh. July is the weakest, 5.57 m/s and 1,405 kWh, so the best month makes 1.6 times the worst. November to March brings in 43% of the year's output in Faulk County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.48 m/s | 1,978 kWh | $288 |
| February | 6.23 m/s | 1,644 kWh | $240 |
| March | 6.57 m/s | 2,034 kWh | $297 |
| April | 6.84 m/s | 2,130 kWh | $311 |
| May | 6.63 m/s | 2,068 kWh | $302 |
| June | 6.05 m/s | 1,647 kWh | $240 |
| July | 5.57 m/s | 1,405 kWh | $205 |
| August | 5.63 m/s | 1,444 kWh | $211 |
| September | 6.51 m/s | 1,931 kWh | $282 |
| October | 6.85 m/s | 2,207 kWh | $322 |
| November | 6.54 m/s | 1,947 kWh | $284 |
| December | 6.40 m/s | 1,928 kWh | $281 |
What a taller tower would buy
Measured at 10 m the wind in Faulk County averages 5.03 m/s; at 50 m it is 7.09 m/s. That gives a shear exponent of 0.213, typical of ordinary open country. Going from 20 m to 50 m takes output from 18,469 to 27,684 kWh a year, 50% 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 | 5.83 m/s | 18,469 kWh | 37 years |
| 30 m | 6.36 m/s | 22,366 kWh | 31 years |
| 40 m | 6.76 m/s | 25,318 kWh | 27 years |
| 50 m | 7.09 m/s | 27,684 kWh | 25 years |
Counties around Faulk County
4 of the 6 closest counties are windier at turbine height; the windiest, Walworth County, averages 6.51 m/s.
- Edmunds County, SD: 6.46 m/s, 23,112 kWh, payback 30 years (24 mi)
- Hand County, SD: 6.35 m/s, 22,299 kWh, payback 31 years (37 mi)
- Potter County, SD: 6.43 m/s, 22,891 kWh, payback 30 years (39 mi)
- Hyde County, SD: 6.4 m/s, 22,669 kWh, payback 30 years (40 mi)
- Spink County, SD: 6.32 m/s, 22,077 kWh, payback 31 years (41 mi)
- Walworth County, SD: 6.51 m/s, 23,481 kWh, payback 29 years (49 mi)
Sun versus wind in Faulk County
Faulk County gets 4.1 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,197 kWh a year; one kW of the turbine above makes 2,237. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.9 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.