Wind Turbine Payback in Clay County, AR
Wind turbine payback in Clay 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 Clay County, AR averages 4.25 m/s (9.5 mph). A 10 kW turbine there would make about 7,897 kWh a year, worth $1,085 at AR's 13.74¢/kWh. Against an installed cost of about $100,000, that is a payback of 92 years, and the turbine is built to last about 20.
What to do in Clay County
A home turbine is not worth buying for savings in Clay County unless your spot is far windier than the county average, 8.4 m/s at the hub against 4.25 m/s here. Per kW, solar panels would make about 1,276 kWh a year here against the turbine's 790, so get a solar quote first.
What would have to change
- Power would have to cost 63¢/kWh, 4.6 times what AR pays now.
- Or the average wind at the hub would have to be 8.4 m/s instead of 4.25. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of AR
Clay County is the 1,914th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in AR is Mississippi County at 5.35 m/s, payback 49 years.
Month by month in Clay County
March is the strongest month here, at 5.05 m/s and about 1,091 kWh. July is the weakest, 3.17 m/s and 266 kWh, so the best month makes 4.1 times the worst. November to March brings in 55% of the year's output in Clay County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.78 m/s | 944 kWh | $130 |
| February | 4.93 m/s | 925 kWh | $127 |
| March | 5.05 m/s | 1,091 kWh | $150 |
| April | 5.11 m/s | 1,089 kWh | $150 |
| May | 4.28 m/s | 684 kWh | $94 |
| June | 3.58 m/s | 381 kWh | $52 |
| July | 3.17 m/s | 266 kWh | $37 |
| August | 3.21 m/s | 278 kWh | $38 |
| September | 3.58 m/s | 381 kWh | $52 |
| October | 4.22 m/s | 656 kWh | $90 |
| November | 4.56 m/s | 800 kWh | $110 |
| December | 4.59 m/s | 840 kWh | $115 |
What a taller tower would buy
Measured at 10 m the wind in Clay County averages 2.96 m/s; at 50 m it is 5.03 m/s. That gives a shear exponent of 0.329, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 5,257 to 12,737 kWh a year, 142% 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 | 3.72 m/s | 5,257 kWh | over 100 years |
| 30 m | 4.25 m/s | 7,908 kWh | 92 years |
| 40 m | 4.67 m/s | 10,407 kWh | 70 years |
| 50 m | 5.03 m/s | 12,737 kWh | 57 years |
Counties around Clay County
3 of the 6 closest counties are windier at turbine height; the windiest, Dunklin County, averages 5.35 m/s.
- Greene County, AR: 4.96 m/s, 12,266 kWh, payback 59 years (19 mi)
- Butler County, MO: 4.25 m/s, 7,897 kWh, payback 89 years (24 mi)
- Dunklin County, MO: 5.35 m/s, 14,963 kWh, payback 47 years (25 mi)
- Ripley County, MO: 4.25 m/s, 7,897 kWh, payback 89 years (32 mi)
- Randolph County, AR: 3.38 m/s, 3,868 kWh, payback over 100 years (34 mi)
- Pemiscot County, MO: 5.35 m/s, 14,963 kWh, payback 47 years (37 mi)
Sun versus wind in Clay County
Clay County gets 4.37 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,276 kWh a year; one kW of the turbine above makes 790. Kilowatt for kilowatt, panels make 1.6 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.