Wind · Analysis

California's first wind farms are old enough to rebuild

The turbines in Tehachapi and San Gorgonio passes date to the early 1980s. Repowering swaps them for fewer, bigger machines, and reopens old questions about eagles and permits.

BY THE RENEWABLE ENERGY LA EDITORS · FILED OCTOBER 10, 2026 · 6 MIN READ ·

What a rebuild actually swaps

Start with the mechanics, because the before-and-after is easy to picture. A 1980s wind farm packed in as many small turbines as the land would hold, sometimes thousands of them, each one short and fast-spinning. A repowered site does the opposite: it clears most of those out and sets down far fewer towers, each taller, with longer blades that turn slowly.

A modern turbine can be rated at several megawatts (a megawatt is a million watts, very roughly enough to serve a few hundred homes at a given moment), where an early-1980s machine might have been rated in the tens or low hundreds of kilowatts. So a site can cut its turbine count by a large fraction and still make more power than before. The exact gain depends on the wind, the model, and how many towers the county will allow, so treat any single headline figure with caution.

The eagle question nobody can skip

California's hardest lesson on this sits at Altamont Pass, east of the Bay Area rather than down here, but it shapes every permit in the state. Altamont's dense old turbines killed golden eagles and other raptors for decades, enough that repowering there was driven partly by the goal of bringing those deaths down. The passes that feed the LA basin carry their own raptor traffic, and no regulator treats a rebuild as free of that risk.

Federal law here is the Bald and Golden Eagle Protection Act, enforced by the US Fish and Wildlife Service. A wind project that might kill eagles can apply for an incidental take permit (a federal authorization that allows a set, monitored number of accidental deaths in exchange for steps to avoid and offset them). Getting one takes surveys, modeling, and time, and the agency can say no. Repowering can lower the body count by removing the worst old turbines, but it does not make the permit question disappear.

The permitting path in California

Keep your own situation in view here, because the path is why rebuilds move slowly even when the economics look good. A repowering project in Kern, Riverside, or Alameda county usually needs a conditional use permit (a county land-use approval for a specific project on specific land) and a review under the California Environmental Quality Act, the state law that makes agencies study and disclose a project's environmental effects before approving it. Both invite public comment, and both can be appealed.

On top of that sits the grid. A rebuilt farm has to get back in line through the interconnection queue (the waiting list the grid operator uses to study and connect new projects) run by the California Independent System Operator, the nonprofit that operates most of the state's grid. Transmission out of Tehachapi is finite, and schedules slip. If you hear a project announced this year, assume the steel may not turn for a while, and watch the filings rather than the press release.

Worth watching this month

1. Whether Kern County's planning department posts any new conditional use permit applications for Tehachapi-area wind repowering, which would be the first public sign a rebuild is real.

2. Any eagle incidental take permit notices or draft environmental reviews from the US Fish and Wildlife Service Pacific Southwest region, which tend to signal a project is serious about its bird risk.

3. LADWP board agendas for anything touching the Pine Tree Wind Project or new wind power contracts, usually routine but worth a scan.

4. Updates to the California Independent System Operator interconnection queue for Kern and Riverside county wind, a slow but telling indicator of what might actually get built.

5. State environmental filings (posted through California's CEQA clearinghouse) for repowering in the San Gorgonio or Tehachapi passes, which open the public comment windows that matter.

Where this dispatch reads

US Fish and Wildlife Service, Eagle Management and Permits (federal agency), www.fws.gov/program/eagle-management, How federal eagle take permits work and why wind projects near raptor habitat need them.
California Energy Commission, wind energy data (state agency), www.energy.ca.gov/data-reports/energy-almanac, State figures on where California's wind capacity sits, including the Tehachapi and San Gorgonio areas.
California Independent System Operator, generator interconnection (grid operator), www.caiso.com/participate/interconnection, The grid operator's queue and process for connecting new or rebuilt projects to the system.
LADWP, Pine Tree Wind Project (city utility), www.ladwp.com, The city's own wind farm in the Tehachapi Mountains, a working example of LA-owned wind.
Southern California Edison, Tehachapi Renewable Transmission Project (utility), www.sce.com, The transmission that carries mountain and desert wind into the LA basin.

Questions readers have asked

Does repowering mean more wind power for Los Angeles?

Usually yes, because the new turbines are far larger than the ones they replace, so a site can make more electricity even with fewer towers. How much more depends on the wind and the project, so be wary of any single number before the final design is public.

Will my LADWP or SCE bill change because of a rebuild?

Not in any direct, line-item way. Wind repowering affects a utility's power supply and long-term costs, not a separate charge on your statement, and any rate effect would be small and slow.

Why are eagles such a big deal at these sites?

The same mountain passes that make strong, steady wind also funnel raptors that hunt and migrate through them. Old, densely packed turbines killed eagles at places like Altamont Pass, so every California rebuild now has to answer for that risk before it is approved.

Who actually decides whether a repowering project happens?

It takes more than one yes. The county approves the land use, the state reviews the environmental effects under CEQA, the US Fish and Wildlife Service handles eagle permits, and the grid operator decides when and how it can connect.