Wind Turbine Payback in Johnson County, NE
Wind turbine payback in Johnson 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 Johnson County, NE averages 6.31 m/s (14.1 mph). A 10 kW turbine there would make about 22,003 kWh a year, worth $2,843 at NE's 12.92¢/kWh. Against an installed cost of about $100,000, that is a payback of 35 years, and the turbine is built to last about 20.
What to do in Johnson County
A home turbine is not worth buying for savings in Johnson County unless your spot is far windier than the county average, 8.8 m/s at the hub against 6.31 m/s here. Per kW, solar panels would make about 1,259 kWh a year here against the turbine's 2,200, so get a solar quote first.
What would have to change
- Power would have to cost 23¢/kWh, 1.8 times what NE pays now.
- Or the average wind at the hub would have to be 8.8 m/s instead of 6.31. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of NE
Johnson County is the 460th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in NE is Cherry County at 6.83 m/s, payback 30 years.
Month by month in Johnson County
April is the strongest month here, at 7.17 m/s and about 2,324 kWh. August is the weakest, 5.10 m/s and 1,120 kWh, so the best month makes 2.1 times the worst. November to March brings in 46% of the year's output in Johnson County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 6.58 m/s | 2,036 kWh | $263 |
| February | 6.56 m/s | 1,829 kWh | $236 |
| March | 6.86 m/s | 2,213 kWh | $286 |
| April | 7.17 m/s | 2,324 kWh | $300 |
| May | 6.46 m/s | 1,963 kWh | $254 |
| June | 6.01 m/s | 1,628 kWh | $210 |
| July | 5.20 m/s | 1,182 kWh | $153 |
| August | 5.10 m/s | 1,120 kWh | $145 |
| September | 6.12 m/s | 1,694 kWh | $219 |
| October | 6.59 m/s | 2,041 kWh | $264 |
| November | 6.73 m/s | 2,061 kWh | $266 |
| December | 6.42 m/s | 1,941 kWh | $251 |
What a taller tower would buy
Measured at 10 m the wind in Johnson County averages 4.94 m/s; at 50 m it is 7.07 m/s. That gives a shear exponent of 0.223, typical of ordinary open country. Going from 20 m to 50 m takes output from 17,957 to 27,542 kWh a year, 53% 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 | 5.76 m/s | 17,957 kWh | 43 years |
| 30 m | 6.31 m/s | 21,994 kWh | 35 years |
| 40 m | 6.73 m/s | 25,070 kWh | 31 years |
| 50 m | 7.07 m/s | 27,542 kWh | 28 years |
Counties around Johnson County
3 of the 6 closest counties are windier at turbine height; the windiest, Gage County, averages 6.42 m/s.
- Pawnee County, NE: 6.34 m/s, 22,225 kWh, payback 35 years (18 mi)
- Otoe County, NE: 6.31 m/s, 22,003 kWh, payback 35 years (18 mi)
- Nemaha County, NE: 6.17 m/s, 20,965 kWh, payback 37 years (22 mi)
- Gage County, NE: 6.42 m/s, 22,817 kWh, payback 34 years (24 mi)
- Richardson County, NE: 6.2 m/s, 21,187 kWh, payback 37 years (34 mi)
- Lancaster County, NE: 6.41 m/s, 22,743 kWh, payback 34 years (35 mi)
Sun versus wind in Johnson County
Johnson 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 2,200. This is one of the rare places where a kilowatt of turbine out-produces a kilowatt of panels, by 1.7 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.