Wind Turbine Payback in Hempstead County, AR
Wind turbine payback in Hempstead 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 Hempstead County, AR averages 3.55 m/s (7.9 mph). A 10 kW turbine there would make about 4,530 kWh a year, worth $622 at AR's 13.74¢/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 Hempstead County
A home turbine is not worth buying for savings in Hempstead County unless your spot is far windier than the county average, 8.4 m/s at the hub against 3.55 m/s here. Per kW, solar panels would make about 1,314 kWh a year here against the turbine's 453, so get a solar quote first.
What would have to change
- Power would have to cost 110¢/kWh, 8.0 times what AR pays now.
- Or the average wind at the hub would have to be 8.4 m/s instead of 3.55. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of AR
Hempstead County is the 2,459th 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 Hempstead County
April is the strongest month here, at 4.13 m/s and about 594 kWh. August is the weakest, 2.85 m/s and 185 kWh, so the best month makes 3.2 times the worst. November to March brings in 52% of the year's output in Hempstead County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.78 m/s | 470 kWh | $65 |
| February | 3.91 m/s | 472 kWh | $65 |
| March | 4.07 m/s | 588 kWh | $81 |
| April | 4.13 m/s | 594 kWh | $82 |
| May | 3.67 m/s | 427 kWh | $59 |
| June | 3.16 m/s | 255 kWh | $35 |
| July | 2.86 m/s | 187 kWh | $26 |
| August | 2.85 m/s | 185 kWh | $25 |
| September | 3.19 m/s | 264 kWh | $36 |
| October | 3.55 m/s | 383 kWh | $53 |
| November | 3.81 m/s | 467 kWh | $64 |
| December | 3.72 m/s | 445 kWh | $61 |
What a taller tower would buy
Measured at 10 m the wind in Hempstead County averages 2.3 m/s; at 50 m it is 4.35 m/s. That gives a shear exponent of 0.396, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 2,679 to 8,460 kWh a year, 216% 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 | 3.03 m/s | 2,679 kWh | over 100 years |
| 30 m | 3.55 m/s | 4,543 kWh | over 100 years |
| 40 m | 3.98 m/s | 6,488 kWh | over 100 years |
| 50 m | 4.35 m/s | 8,460 kWh | 86 years |
Counties around Hempstead County
1 of the 6 closest counties is windier at turbine height; the windiest, Little River County, averages 4.42 m/s.
- Nevada County, AR: 3.11 m/s, 2,938 kWh, payback over 100 years (21 mi)
- Pike County, AR: 3.28 m/s, 3,506 kWh, payback over 100 years (29 mi)
- Howard County, AR: 3.28 m/s, 3,506 kWh, payback over 100 years (30 mi)
- Miller County, AR: 3.55 m/s, 4,530 kWh, payback over 100 years (33 mi)
- Little River County, AR: 4.42 m/s, 8,865 kWh, payback 82 years (33 mi)
- Lafayette County, AR: 3.39 m/s, 3,905 kWh, payback over 100 years (34 mi)
Sun versus wind in Hempstead County
Hempstead County gets 4.5 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,314 kWh a year; one kW of the turbine above makes 453. Kilowatt for kilowatt, panels make 2.9 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.