TurbinePayback

Wind Turbine Payback in Carter County, OK

Wind turbine payback in Carter 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 Carter County, OK averages 6.07 m/s (13.6 mph). A 10 kW turbine there would make about 20,223 kWh a year, worth $2,793 at OK's 13.81¢/kWh. Against an installed cost of about $100,000, that is a payback of 36 years, and the turbine is built to last about 20.

What to do in Carter County

A home turbine is not worth buying for savings in Carter County unless your spot is far windier than the county average, 8.4 m/s at the hub against 6.07 m/s here. Per kW, solar panels would make about 1,399 kWh a year here against the turbine's 2,022, so get a solar quote first.

What would have to change

Against the rest of OK

Carter County is the 717th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in OK is Cimarron County at 6.82 m/s, payback 28 years.

Month by month in Carter County

April is the strongest month here, at 7.06 m/s and about 2,260 kWh. August is the weakest, 4.97 m/s and 1,047 kWh, so the best month makes 2.2 times the worst. November to March brings in 47% of the year's output in Carter County.

MonthWind at 30 mOutputWorth
January6.25 m/s1,829 kWh$253
February6.44 m/s1,763 kWh$243
March6.81 m/s2,178 kWh$301
April7.06 m/s2,260 kWh$312
May6.33 m/s1,879 kWh$259
June5.85 m/s1,527 kWh$211
July5.06 m/s1,098 kWh$152
August4.97 m/s1,047 kWh$145
September5.27 m/s1,184 kWh$164
October6.13 m/s1,756 kWh$243
November6.50 m/s1,921 kWh$265
December6.19 m/s1,795 kWh$248

What a taller tower would buy

Measured at 10 m the wind in Carter County averages 4.69 m/s; at 50 m it is 6.84 m/s. That gives a shear exponent of 0.234, typical of ordinary open country. Going from 20 m to 50 m takes output from 16,181 to 25,892 kWh a year, 60% more, before counting the extra cost of the taller tower. Why tower height decides it explains the shear behind these numbers.

Hub heightAverage windOutputPayback
20 m5.52 m/s16,181 kWh45 years
30 m6.07 m/s20,218 kWh36 years
40 m6.49 m/s23,348 kWh31 years
50 m6.84 m/s25,892 kWh28 years

Counties around Carter County

None of the 6 closest counties is windier than Carter County.

Sun versus wind in Carter County

Carter County gets 4.79 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,399 kWh a year; one kW of the turbine above makes 2,022. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.4 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.