Wind Turbine Payback in Calaveras County, CA
Wind turbine payback in Calaveras 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 Calaveras County, CA averages 3.22 m/s (7.2 mph). A 10 kW turbine there would make about 3,299 kWh a year, worth $1,075 at CA's 32.58¢/kWh. Against an installed cost of about $100,000, that is a payback of 93 years, and the turbine is built to last about 20.
What to do in Calaveras County
A home turbine is not worth buying for savings in Calaveras County unless your spot is far windier than the county average, 5.4 m/s at the hub against 3.22 m/s here. Per kW, solar panels would make about 1,527 kWh a year here against the turbine's 330, so get a solar quote first.
What would have to change
- Power would have to cost 152¢/kWh, 4.7 times what CA pays now.
- Or the average wind at the hub would have to be 5.4 m/s instead of 3.22. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of CA
Calaveras County is the 2,857th windiest of 3,144 US counties at turbine height; the national middle is 4.79 m/s. The windiest in CA is San Francisco County at 6.53 m/s, payback 13 years.
Month by month in Calaveras County
December is the strongest month here, at 3.80 m/s and about 476 kWh. August is the weakest, 2.70 m/s and 152 kWh, so the best month makes 3.1 times the worst. November to March brings in 56% of the year's output in Calaveras County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.61 m/s | 406 kWh | $132 |
| February | 3.74 m/s | 408 kWh | $133 |
| March | 3.37 m/s | 326 kWh | $106 |
| April | 3.23 m/s | 274 kWh | $89 |
| May | 3.14 m/s | 258 kWh | $84 |
| June | 3.11 m/s | 243 kWh | $79 |
| July | 2.92 m/s | 201 kWh | $65 |
| August | 2.70 m/s | 152 kWh | $50 |
| September | 2.78 m/s | 163 kWh | $53 |
| October | 3.02 m/s | 225 kWh | $73 |
| November | 3.25 m/s | 279 kWh | $91 |
| December | 3.80 m/s | 476 kWh | $155 |
What a taller tower would buy
Measured at 10 m the wind in Calaveras County averages 2.49 m/s; at 50 m it is 3.63 m/s. That gives a shear exponent of 0.234, typical of ordinary open country. Going from 20 m to 50 m takes output from 2,397 to 4,862 kWh a year, 103% 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 | 2.93 m/s | 2,397 kWh | over 100 years |
| 30 m | 3.22 m/s | 3,302 kWh | 93 years |
| 40 m | 3.45 m/s | 4,115 kWh | 75 years |
| 50 m | 3.63 m/s | 4,862 kWh | 63 years |
Counties around Calaveras County
6 of the 6 closest counties are windier at turbine height; the windiest, Stanislaus County, averages 4.35 m/s.
- Amador County, CA: 3.59 m/s, 4,694 kWh, payback 65 years (18 mi)
- Tuolumne County, CA: 3.32 m/s, 3,648 kWh, payback 84 years (34 mi)
- El Dorado County, CA: 3.43 m/s, 4,056 kWh, payback 76 years (41 mi)
- San Joaquin County, CA: 4.09 m/s, 7,038 kWh, payback 44 years (43 mi)
- Sacramento County, CA: 3.82 m/s, 5,707 kWh, payback 54 years (46 mi)
- Stanislaus County, CA: 4.35 m/s, 8,460 kWh, payback 36 years (50 mi)
Sun versus wind in Calaveras County
Calaveras County gets 5.23 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,527 kWh a year; one kW of the turbine above makes 330. Kilowatt for kilowatt, panels make 4.6 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.