Wind Turbine Payback in Lake County, CA
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, CA averages 3.92 m/s (8.8 mph). A 10 kW turbine there would make about 6,182 kWh a year, worth $2,014 at CA's 32.58¢/kWh. Against an installed cost of about $100,000, that is a payback of 50 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, 5.4 m/s at the hub against 3.92 m/s here. Per kW, solar panels would make about 1,504 kWh a year here against the turbine's 618, so get a solar quote first.
What would have to change
- Power would have to cost 81¢/kWh, 2.5 times what CA pays now.
- Or the average wind at the hub would have to be 5.4 m/s instead of 3.92. A taller tower or an exposed ridge can add some of that; a rooftop never will.
Against the rest of CA
Lake County is the 2,118th 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 Lake County
December is the strongest month here, at 4.37 m/s and about 726 kWh. August is the weakest, 3.18 m/s and 269 kWh, so the best month makes 2.7 times the worst. November to March brings in 51% of the year's output in Lake County.
| Month | Wind at 30 m | Output | Worth |
|---|---|---|---|
| January | 4.14 m/s | 619 kWh | $202 |
| February | 4.39 m/s | 667 kWh | $217 |
| March | 4.23 m/s | 663 kWh | $216 |
| April | 4.11 m/s | 587 kWh | $191 |
| May | 3.91 m/s | 521 kWh | $170 |
| June | 3.79 m/s | 456 kWh | $149 |
| July | 3.24 m/s | 287 kWh | $94 |
| August | 3.18 m/s | 269 kWh | $88 |
| September | 3.58 m/s | 381 kWh | $124 |
| October | 4.05 m/s | 580 kWh | $189 |
| November | 4.05 m/s | 561 kWh | $183 |
| December | 4.37 m/s | 726 kWh | $237 |
What a taller tower would buy
Measured at 10 m the wind in Lake County averages 2.95 m/s; at 50 m it is 4.47 m/s. That gives a shear exponent of 0.258, typical of ordinary open country. Going from 20 m to 50 m takes output from 4,444 to 9,160 kWh a year, 106% 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 | 3.53 m/s | 4,444 kWh | 69 years |
| 30 m | 3.92 m/s | 6,173 kWh | 50 years |
| 40 m | 4.22 m/s | 7,732 kWh | 40 years |
| 50 m | 4.47 m/s | 9,160 kWh | 34 years |
Counties around Lake County
3 of the 6 closest counties are windier at turbine height; the windiest, Sonoma County, averages 4.66 m/s.
- Colusa County, CA: 3.92 m/s, 6,182 kWh, payback 50 years (28 mi)
- Glenn County, CA: 3.8 m/s, 5,614 kWh, payback 55 years (39 mi)
- Sonoma County, CA: 4.66 m/s, 10,320 kWh, payback 30 years (41 mi)
- Mendocino County, CA: 3.87 m/s, 5,942 kWh, payback 52 years (44 mi)
- Napa County, CA: 3.97 m/s, 6,428 kWh, payback 48 years (47 mi)
- Yolo County, CA: 4.42 m/s, 8,865 kWh, payback 35 years (54 mi)
Sun versus wind in Lake County
Lake County gets 5.15 kWh of sunshine per square metre a day on average. One kW of solar panels here would make roughly 1,504 kWh a year; one kW of the turbine above makes 618. Kilowatt for kilowatt, panels make 2.4 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.