Wind Turbine Payback in El Dorado County, CA
Wind turbine payback in El Dorado 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 El Dorado County, CA averages 3.43 m/s (7.7 mph). A 10 kW turbine there would make about 4,056 kWh a year, worth $1,321 at CA's 32.58¢/kWh. Against an installed cost of about $100,000, that is a payback of 76 years, and the turbine is built to last about 20.
What to do in El Dorado County
A home turbine is not worth buying for savings in El Dorado County unless your spot is far windier than the county average, 5.4 m/s at the hub against 3.43 m/s here. Per kW, solar panels would make about 1,527 kWh a year here against the turbine's 406, so get a solar quote first.
What would have to change
- Power would have to cost 123¢/kWh, 3.8 times what CA pays now.
- Or the average wind at the hub would have to be 5.4 m/s instead of 3.43. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of CA
El Dorado County is the 2,587th 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 El Dorado County
December is the strongest month here, at 3.96 m/s and about 541 kWh. July is the weakest, 2.88 m/s and 192 kWh, so the best month makes 2.8 times the worst. November to March brings in 56% of the year's output in El Dorado County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 3.91 m/s | 520 kWh | $169 |
| February | 3.86 m/s | 451 kWh | $147 |
| March | 3.66 m/s | 422 kWh | $137 |
| April | 3.36 m/s | 312 kWh | $102 |
| May | 3.17 m/s | 265 kWh | $86 |
| June | 3.12 m/s | 243 kWh | $79 |
| July | 2.88 m/s | 192 kWh | $63 |
| August | 2.95 m/s | 208 kWh | $68 |
| September | 3.24 m/s | 278 kWh | $91 |
| October | 3.42 m/s | 341 kWh | $111 |
| November | 3.63 m/s | 400 kWh | $130 |
| December | 3.96 m/s | 541 kWh | $176 |
What a taller tower would buy
Measured at 10 m the wind in El Dorado County averages 2.37 m/s; at 50 m it is 4.07 m/s. That gives a shear exponent of 0.336, typical of rough, sheltered ground: trees or buildings slow the low wind a lot. Going from 20 m to 50 m takes output from 2,576 to 6,934 kWh a year, 169% 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 | 2.99 m/s | 2,576 kWh | over 100 years |
| 30 m | 3.43 m/s | 4,049 kWh | 76 years |
| 40 m | 3.78 m/s | 5,504 kWh | 56 years |
| 50 m | 4.07 m/s | 6,934 kWh | 44 years |
Counties around El Dorado County
3 of the 6 closest counties are windier at turbine height; the windiest, Carson City, averages 3.75 m/s.
- Placer County, CA: 3.43 m/s, 4,056 kWh, payback 76 years (22 mi)
- Amador County, CA: 3.59 m/s, 4,694 kWh, payback 65 years (25 mi)
- Nevada County, CA: 3.32 m/s, 3,648 kWh, payback 84 years (38 mi)
- Calaveras County, CA: 3.22 m/s, 3,299 kWh, payback 93 years (41 mi)
- Alpine County, CA: 3.53 m/s, 4,449 kWh, payback 69 years (41 mi)
- Carson City, NV: 3.75 m/s, 5,387 kWh, payback over 100 years (49 mi)
Sun versus wind in El Dorado County
El Dorado 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 406. Kilowatt for kilowatt, panels make 3.8 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.