Wind Turbine Payback in Lake County, TN
Wind turbine payback in Lake 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 Lake County, TN averages 5.54 m/s (12.4 mph). A 10 kW turbine there would make about 16,326 kWh a year, worth $2,253 at TN's 13.8¢/kWh. Against an installed cost of about $100,000, that is a payback of 44 years, and the turbine is built to last about 20.
What to do in Lake County
A home turbine is not worth buying for savings in Lake County unless your spot is far windier than the county average, 8.4 m/s at the hub against 5.54 m/s here. Per kW, solar panels would make about 1,276 kWh a year here against the turbine's 1,633, so get a solar quote first.
What would have to change
- Power would have to cost 31¢/kWh, 2.2 times what TN pays now.
- Or the average wind at the hub would have to be 8.4 m/s instead of 5.54. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of TN
Lake County is the 1,186th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. It is the windiest county in TN.
Month by month in Lake County
April is the strongest month here, at 6.66 m/s and about 2,020 kWh. July is the weakest, 4.07 m/s and 590 kWh, so the best month makes 3.4 times the worst. November to March brings in 53% of the year's output in Lake County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.24 m/s | 1,827 kWh | $252 |
| February | 6.32 m/s | 1,695 kWh | $234 |
| March | 6.49 m/s | 1,982 kWh | $274 |
| April | 6.66 m/s | 2,020 kWh | $279 |
| May | 5.62 m/s | 1,438 kWh | $198 |
| June | 4.65 m/s | 843 kWh | $116 |
| July | 4.07 m/s | 590 kWh | $81 |
| August | 4.12 m/s | 610 kWh | $84 |
| September | 4.71 m/s | 875 kWh | $121 |
| October | 5.56 m/s | 1,400 kWh | $193 |
| November | 6.11 m/s | 1,687 kWh | $233 |
| December | 6.07 m/s | 1,721 kWh | $237 |
What a taller tower would buy
Measured at 10 m the wind in Lake County averages 4.27 m/s; at 50 m it is 6.26 m/s. That gives a shear exponent of 0.238, typical of ordinary open country. Going from 20 m to 50 m takes output from 12,761 to 21,632 kWh a year, 70% 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 | 5.03 m/s | 12,761 kWh | 57 years |
| 30 m | 5.54 m/s | 16,351 kWh | 44 years |
| 40 m | 5.94 m/s | 19,232 kWh | 38 years |
| 50 m | 6.26 m/s | 21,632 kWh | 34 years |
Counties around Lake County
None of the 6 closest counties is windier than Lake County.
- Pemiscot County, MO: 5.35 m/s, 14,963 kWh, payback 47 years (19 mi)
- Obion County, TN: 5.54 m/s, 16,326 kWh, payback 44 years (19 mi)
- Dyer County, TN: 5.41 m/s, 15,390 kWh, payback 47 years (20 mi)
- New Madrid County, MO: 5.54 m/s, 16,326 kWh, payback 43 years (20 mi)
- Fulton County, KY: 5.54 m/s, 16,326 kWh, payback 43 years (22 mi)
- Dunklin County, MO: 5.35 m/s, 14,963 kWh, payback 47 years (34 mi)
Sun versus wind in Lake County
Lake County gets 4.37 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,276 kWh a year; one kW of the turbine above makes 1,633. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.3 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.