Wind Turbine Payback in Polk County, FL
Wind turbine payback in Polk 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 Polk County, FL averages 4.44 m/s (9.9 mph). A 10 kW turbine there would make about 8,982 kWh a year, worth $1,376 at FL's 15.32¢/kWh. Against an installed cost of about $100,000, that is a payback of 73 years, and the turbine is built to last about 20.
What to do in Polk County
A home turbine is not worth buying for savings in Polk County unless your spot is far windier than the county average, 7.8 m/s at the hub against 4.44 m/s here. Per kW, solar panels would make about 1,463 kWh a year here against the turbine's 898, so get a solar quote first.
What would have to change
- Power would have to cost 56¢/kWh, 3.6 times what FL pays now.
- Or the average wind at the hub would have to be 7.8 m/s instead of 4.44. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of FL
Polk County is the 1,788th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in FL is Brevard County at 5.62 m/s, payback 39 years.
Month by month in Polk County
January is the strongest month here, at 5.16 m/s and about 1,157 kWh. July is the weakest, 3.11 m/s and 249 kWh, so the best month makes 4.6 times the worst. November to March brings in 57% of the year's output in Polk County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 5.16 m/s | 1,157 kWh | $177 |
| February | 4.97 m/s | 945 kWh | $145 |
| March | 5.14 m/s | 1,147 kWh | $176 |
| April | 4.84 m/s | 941 kWh | $144 |
| May | 4.34 m/s | 713 kWh | $109 |
| June | 3.53 m/s | 365 kWh | $56 |
| July | 3.11 m/s | 249 kWh | $38 |
| August | 3.33 m/s | 314 kWh | $48 |
| September | 4.08 m/s | 573 kWh | $88 |
| October | 4.79 m/s | 948 kWh | $145 |
| November | 5.05 m/s | 1,061 kWh | $163 |
| December | 5.03 m/s | 1,081 kWh | $166 |
What a taller tower would buy
Measured at 10 m the wind in Polk County averages 3.32 m/s; at 50 m it is 5.09 m/s. That gives a shear exponent of 0.266, typical of ordinary open country. Going from 20 m to 50 m takes output from 6,522 to 13,146 kWh a year, 102% 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 | 3.99 m/s | 6,522 kWh | over 100 years |
| 30 m | 4.44 m/s | 9,002 kWh | 73 years |
| 40 m | 4.8 m/s | 11,190 kWh | 58 years |
| 50 m | 5.09 m/s | 13,146 kWh | 50 years |
Counties around Polk County
4 of the 6 closest counties are windier at turbine height; the windiest, Hillsborough County, averages 4.66 m/s.
- Hardee County, FL: 4.37 m/s, 8,575 kWh, payback 76 years (33 mi)
- Osceola County, FL: 4.57 m/s, 9,763 kWh, payback 67 years (35 mi)
- Hillsborough County, FL: 4.66 m/s, 10,320 kWh, payback 63 years (42 mi)
- Orange County, FL: 4.65 m/s, 10,257 kWh, payback 64 years (45 mi)
- Highlands County, FL: 4.47 m/s, 9,160 kWh, payback 71 years (47 mi)
- DeSoto County, FL: 4.34 m/s, 8,403 kWh, payback 78 years (53 mi)
Sun versus wind in Polk County
Polk County gets 5.01 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,463 kWh a year; one kW of the turbine above makes 898. Kilowatt for kilowatt, panels make 1.6 times as much here as the turbine. 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.