Wind Turbine Payback in Potter County, SD
Wind turbine payback in Potter 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 Potter County, SD averages 6.43 m/s (14.4 mph). A 10 kW turbine there would make about 22,891 kWh a year, worth $3,337 at SD's 14.58¢/kWh. Against an installed cost of about $100,000, that is a payback of 30 years, and the turbine is built to last about 20.
What to do in Potter County
A home turbine is not worth buying for savings in Potter County unless your spot is far windier than the county average, 8.1 m/s at the hub against 6.43 m/s here. Per kW, solar panels would make about 1,197 kWh a year here against the turbine's 2,289, 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 6.43. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of SD
Potter County is the 290th 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 Potter County
October is the strongest month here, at 6.91 m/s and about 2,244 kWh. July is the weakest, 5.75 m/s and 1,518 kWh, so the best month makes 1.5 times the worst. November to March brings in 42% of the year's output in Potter County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.50 m/s | 1,987 kWh | $290 |
| February | 6.22 m/s | 1,637 kWh | $239 |
| March | 6.69 m/s | 2,105 kWh | $307 |
| April | 6.97 m/s | 2,203 kWh | $321 |
| May | 6.71 m/s | 2,122 kWh | $309 |
| June | 6.17 m/s | 1,721 kWh | $251 |
| July | 5.75 m/s | 1,518 kWh | $221 |
| August | 5.78 m/s | 1,535 kWh | $224 |
| September | 6.59 m/s | 1,978 kWh | $288 |
| October | 6.91 m/s | 2,244 kWh | $327 |
| November | 6.53 m/s | 1,945 kWh | $284 |
| December | 6.41 m/s | 1,931 kWh | $282 |
What a taller tower would buy
Measured at 10 m the wind in Potter County averages 5.13 m/s; at 50 m it is 7.15 m/s. That gives a shear exponent of 0.206, typical of ordinary open country. Going from 20 m to 50 m takes output from 19,113 to 28,109 kWh a year, 47% 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 | 5.92 m/s | 19,113 kWh | 36 years |
| 30 m | 6.44 m/s | 22,934 kWh | 30 years |
| 40 m | 6.83 m/s | 25,811 kWh | 27 years |
| 50 m | 7.15 m/s | 28,109 kWh | 24 years |
Counties around Potter County
2 of the 6 closest counties are windier at turbine height; the windiest, Walworth County, averages 6.51 m/s.
- Sully County, SD: 6.35 m/s, 22,299 kWh, payback 31 years (24 mi)
- Walworth County, SD: 6.51 m/s, 23,481 kWh, payback 29 years (26 mi)
- Faulk County, SD: 6.36 m/s, 22,373 kWh, payback 31 years (39 mi)
- Hyde County, SD: 6.4 m/s, 22,669 kWh, payback 30 years (43 mi)
- Dewey County, SD: 6.39 m/s, 22,595 kWh, payback 30 years (43 mi)
- Edmunds County, SD: 6.46 m/s, 23,112 kWh, payback 30 years (44 mi)
Sun versus wind in Potter County
Potter 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 2,289. 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.