Wind Turbine Payback in Lafayette County, MO
Wind turbine payback in Lafayette 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 Lafayette County, MO averages 5.86 m/s (13.1 mph). A 10 kW turbine there would make about 18,669 kWh a year, worth $2,666 at MO's 14.28¢/kWh. Against an installed cost of about $100,000, that is a payback of 38 years, and the turbine is built to last about 20.
What to do in Lafayette County
A home turbine is not worth buying for savings in Lafayette County unless your spot is far windier than the county average, 8.2 m/s at the hub against 5.86 m/s here. Per kW, solar panels would make about 1,226 kWh a year here against the turbine's 1,867, so get a solar quote first.
What would have to change
- Power would have to cost 27¢/kWh, 1.9 times what MO pays now.
- Or the average wind at the hub would have to be 8.2 m/s instead of 5.86. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of MO
Lafayette County is the 1,034th 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 Lafayette County
April is the strongest month here, at 6.79 m/s and about 2,096 kWh. August is the weakest, 4.57 m/s and 829 kWh, so the best month makes 2.5 times the worst. November to March brings in 49% of the year's output in Lafayette County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.32 m/s | 1,874 kWh | $268 |
| February | 6.30 m/s | 1,683 kWh | $240 |
| March | 6.62 m/s | 2,062 kWh | $294 |
| April | 6.79 m/s | 2,096 kWh | $299 |
| May | 5.89 m/s | 1,602 kWh | $229 |
| June | 5.42 m/s | 1,269 kWh | $181 |
| July | 4.61 m/s | 852 kWh | $122 |
| August | 4.57 m/s | 829 kWh | $118 |
| September | 5.19 m/s | 1,136 kWh | $162 |
| October | 6.09 m/s | 1,729 kWh | $247 |
| November | 6.42 m/s | 1,878 kWh | $268 |
| December | 6.17 m/s | 1,780 kWh | $254 |
What a taller tower would buy
Measured at 10 m the wind in Lafayette County averages 4.49 m/s; at 50 m it is 6.63 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 14,689 to 24,362 kWh a year, 66% 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 | 5.31 m/s | 14,689 kWh | 48 years |
| 30 m | 5.86 m/s | 18,661 kWh | 38 years |
| 40 m | 6.28 m/s | 21,791 kWh | 32 years |
| 50 m | 6.63 m/s | 24,362 kWh | 29 years |
Counties around Lafayette County
3 of the 6 closest counties are windier at turbine height; the windiest, Jackson County, averages 5.96 m/s.
- Ray County, MO: 5.89 m/s, 18,890 kWh, payback 37 years (20 mi)
- Johnson County, MO: 5.42 m/s, 15,462 kWh, payback 45 years (23 mi)
- Jackson County, MO: 5.96 m/s, 19,408 kWh, payback 36 years (29 mi)
- Carroll County, MO: 5.89 m/s, 18,890 kWh, payback 37 years (30 mi)
- Saline County, MO: 5.74 m/s, 17,785 kWh, payback 39 years (32 mi)
- Pettis County, MO: 4.81 m/s, 11,276 kWh, payback 62 years (36 mi)
Sun versus wind in Lafayette County
Lafayette County gets 4.2 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,226 kWh a year; one kW of the turbine above makes 1,867. 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.