Wind Turbine Payback in Woodruff County, AR
Wind turbine payback in Woodruff 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 Woodruff County, AR averages 5.12 m/s (11.5 mph). A 10 kW turbine there would make about 13,353 kWh a year, worth $1,835 at AR's 13.74¢/kWh. Against an installed cost of about $100,000, that is a payback of 55 years, and the turbine is built to last about 20.
What to do in Woodruff County
A home turbine is not worth buying for savings in Woodruff County unless your spot is far windier than the county average, 8.4 m/s at the hub against 5.12 m/s here. Per kW, solar panels would make about 1,291 kWh a year here against the turbine's 1,335, so get a solar quote first.
What would have to change
- Power would have to cost 37¢/kWh, 2.7 times what AR pays now.
- Or the average wind at the hub would have to be 8.4 m/s instead of 5.12. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of AR
Woodruff County is the 1,403rd 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 Woodruff County
March is the strongest month here, at 6.04 m/s and about 1,700 kWh. July is the weakest, 3.74 m/s and 453 kWh, so the best month makes 3.8 times the worst. November to March brings in 55% of the year's output in Woodruff County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.81 m/s | 1,557 kWh | $214 |
| February | 5.92 m/s | 1,466 kWh | $201 |
| March | 6.04 m/s | 1,700 kWh | $234 |
| April | 6.05 m/s | 1,650 kWh | $227 |
| May | 5.14 m/s | 1,146 kWh | $157 |
| June | 4.21 m/s | 632 kWh | $87 |
| July | 3.74 m/s | 453 kWh | $62 |
| August | 3.86 m/s | 501 kWh | $69 |
| September | 4.46 m/s | 746 kWh | $103 |
| October | 5.08 m/s | 1,110 kWh | $153 |
| November | 5.63 m/s | 1,396 kWh | $192 |
| December | 5.64 m/s | 1,448 kWh | $199 |
What a taller tower would buy
Measured at 10 m the wind in Woodruff County averages 3.85 m/s; at 50 m it is 5.85 m/s. That gives a shear exponent of 0.260, typical of ordinary open country. Going from 20 m to 50 m takes output from 10,008 to 18,595 kWh a year, 86% 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 | 4.61 m/s | 10,008 kWh | 73 years |
| 30 m | 5.12 m/s | 13,369 kWh | 54 years |
| 40 m | 5.52 m/s | 16,183 kWh | 45 years |
| 50 m | 5.85 m/s | 18,595 kWh | 39 years |
Counties around Woodruff County
2 of the 6 closest counties are windier at turbine height; the windiest, St. Francis County, averages 5.3 m/s.
- Cross County, AR: 5.27 m/s, 14,397 kWh, payback 51 years (28 mi)
- Jackson County, AR: 4.7 m/s, 10,571 kWh, payback 69 years (28 mi)
- White County, AR: 3.89 m/s, 6,037 kWh, payback over 100 years (29 mi)
- St. Francis County, AR: 5.3 m/s, 14,608 kWh, payback 50 years (30 mi)
- Prairie County, AR: 5.12 m/s, 13,353 kWh, payback 55 years (31 mi)
- Monroe County, AR: 4.94 m/s, 12,132 kWh, payback 60 years (36 mi)
Sun versus wind in Woodruff County
Woodruff 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 1,335. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.0 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.