Wind Turbine Payback in Cass County, MO
Wind turbine payback in Cass 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 Cass County, MO averages 5.9 m/s (13.2 mph). A 10 kW turbine there would make about 18,964 kWh a year, worth $2,708 at MO's 14.28¢/kWh. Against an installed cost of about $100,000, that is a payback of 37 years, and the turbine is built to last about 20.
What to do in Cass County
A home turbine is not worth buying for savings in Cass County unless your spot is far windier than the county average, 8.2 m/s at the hub against 5.9 m/s here. Per kW, solar panels would make about 1,259 kWh a year here against the turbine's 1,896, so get a solar quote first.
What would have to change
- Power would have to cost 26¢/kWh, 1.8 times what MO pays now.
- Or the average wind at the hub would have to be 8.2 m/s instead of 5.9. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MO
Cass County is the 988th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in MO is Atchison County at 6.17 m/s, payback 33 years.
Month by month in Cass County
April is the strongest month here, at 6.88 m/s and about 2,149 kWh. August is the weakest, 4.62 m/s and 856 kWh, so the best month makes 2.5 times the worst. November to March brings in 49% of the year's output in Cass County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.31 m/s | 1,869 kWh | $267 |
| February | 6.32 m/s | 1,693 kWh | $242 |
| March | 6.65 m/s | 2,084 kWh | $298 |
| April | 6.88 m/s | 2,149 kWh | $307 |
| May | 5.91 m/s | 1,618 kWh | $231 |
| June | 5.50 m/s | 1,316 kWh | $188 |
| July | 4.63 m/s | 861 kWh | $123 |
| August | 4.62 m/s | 856 kWh | $122 |
| September | 5.20 m/s | 1,141 kWh | $163 |
| October | 6.12 m/s | 1,752 kWh | $250 |
| November | 6.43 m/s | 1,884 kWh | $269 |
| December | 6.17 m/s | 1,780 kWh | $254 |
What a taller tower would buy
Measured at 10 m the wind in Cass County averages 4.52 m/s; at 50 m it is 6.67 m/s. That gives a shear exponent of 0.242, typical of ordinary open country. Going from 20 m to 50 m takes output from 14,916 to 24,655 kWh a year, 65% 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 | 5.34 m/s | 14,916 kWh | 47 years |
| 30 m | 5.89 m/s | 18,923 kWh | 37 years |
| 40 m | 6.32 m/s | 22,072 kWh | 32 years |
| 50 m | 6.67 m/s | 24,655 kWh | 28 years |
Counties around Cass County
3 of the 6 closest counties are windier at turbine height; the windiest, Miami County, averages 6.06 m/s.
- Jackson County, MO: 5.96 m/s, 19,408 kWh, payback 36 years (25 mi)
- Miami County, KS: 6.06 m/s, 20,149 kWh, payback 33 years (26 mi)
- Bates County, MO: 5.9 m/s, 18,964 kWh, payback 37 years (27 mi)
- Johnson County, MO: 5.42 m/s, 15,462 kWh, payback 45 years (30 mi)
- Johnson County, KS: 6.06 m/s, 20,149 kWh, payback 33 years (30 mi)
- Henry County, MO: 5.42 m/s, 15,462 kWh, payback 45 years (35 mi)
Sun versus wind in Cass County
Cass County gets 4.31 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,259 kWh a year; one kW of the turbine above makes 1,896. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.5 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.