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Altamont Pass Wind Farm is one of California’s primary wind energy sources, along with Tehachapi Pass Wind Farm and San Giorgino Pass Wind Farm. Alta Wind Energy Center, the biggest wind farm in the US, is also within Tehachapi.
In 2022, the three regions will deliver 95% of the wind electricity in California.
The Altamont Pass brought some of the earliest wind farms to the grid in the 1970s and 1980s. The Altamont Pass road is very suitable for wind farm development. A $1 billion farm investment spurred the area’s early growth.
At its peak, developers installed 6,200 turbines in the wind resource area of Altamont Pass, which companies operated 26 different projects. In 1986, the wind farms in Altamont could power 250,000 households with 550-gigawatt hours of electricity.
Though owned by different companies, the area is commonly referred to as Altamont Pass Wind farms. The group of wind farm projects that date back to the 1970s in the Altamont Pass area in Contra Costa County and Alameda County, California.
The wind farms referred to as Altamont wind farms also include those in Patterson Pass and Vasco areas, which are north and south of Altamont Pass.
Why is Altamont Pass a good place for a wind farm?
The venturi effect illustrates that the pressure decreases as wind increases in speed. The wind which goes through a mountain pass accelerates, and thus the wind turbines spin consistently.
Altamont Pass is a relatively low mountain pass near the Diablo range at 226-meter elevation.
Though rising only at 226 meters–which is lower than most mountain passes–its elevation carries more wind power at such heights compared to the lower plains. Generally, mountain passes also have good wind currents, making them a good location for wind turbines.
The wide, open, and rolling hills make it suitable for developing multiple wind farms while harnessing wind power efficiently.
How did Altamont Pass Wind farm begin?
The wind turbines started to develop in the 1970s and 80s when California was led by then Gov. Jerry Brown. He also directed the California Energy Commission for the study, which found that mountain passes are good for wind turbines.
During the time, the first and second energy crises of 1973 and 1979 were the backdrop of a growing need to depend more on local sources of energy.
President Jimmy Carter signed the Public Utilities Regulatory Policy Act (PURPA) in 1978. PURPA required the utilities to buy power from producing electricity at less than the utilities’ own cost.
PURPA allowed smaller generators to flourish, especially in California, where the state encouraged generator companies with 80 MW capacity or less and are using renewables as primary sources of electricity. The wind capacity of California grew from 10 MW to 1700 MW in the 1990s.
How many turbines are in the Altamont Pass Wind farm?
Altamont Pass Wind resource area comprises seven wind farms from seven distinct companies. The capacity of the turbines used in the farms varies.
| Wind Farm | Owner | Commisioned | Number of Turbines | Installed Capacity |
|---|---|---|---|---|
| Patterson Pass | EDF Renewables | 1985 | 8 | 20.5 MW |
| Summit Wind | Greenbacker | 2011 | 23 | 57.5 MW |
| Buena Vista Energy | Leeward | 2006 | 38 | 38 MW |
| Diablo Winds | Huntsman Wind | 2005 | 31 | 18 MW |
| Golden Hills | Golden Hills Wind | 2015 | 48 | 81.6 MW |
| Golden Hills North | Golden Hills Wind | 2017 | 20 | 46 MW |
| Vasco Winds | Vasco Winds | 2011 | 34 | 78 MW |
When was Altamont Pass Wind Farm repowered?
Altamont Pass Wind Farms were made of very old, low power turbines. Most turbines reached the end of it’s expected 30 year life, and developers recommissioned them with state of the art turbines.
In separate projects, NextEra Energy Resources (NEER) repowered the Altamont Pass Wind farm three times. NEER removed more than a thousand two decades old turbines and replaced them with newer, taller, more powerful turbines. The older wind turbines that NEER replaced were 100 kW rated turbines.
Summit Wind farm also replaced 568 old wind turbines 100 KW each with 23 GE turbines in 2021, totaling 57.5 MW. East bay community energy agreed to purchase 20 years of electricity from Summit Wind.
In 2022, all but 205 of the original turbines have been replaced or decommissioned.
In 6 wind projects, 195 new turbines replaced thousands of old 100 kW windmills. With current technology, each turbine can replace 15 windmills.
Where is the Altamont Pass Wind Farm?
Altamont Pass Wind farm is located in Contra Costa County and Alameda County, Northern California.
The wind farms can be seen along the scenic views of the I-580 highway, in the segment between I-205 and Livermore, Alameda county. The higher summit provides relief from the busy highway and offers a scenic stretch of windmills across the plains.
The section of the I-580 highway is also a high-traffic road, with more than 160,000 vehicles every day passing through the highway.
Two railroad lines are also near the Altamont Pass road, with one still operational under Union Pacific.
Why is it called the Altamont Pass?
Formerly known as Livermore Pass, Altamont means ‘high mountain’ in Spanish, hence the name for the town, which is 226 meters high. It is not the location of the infamous 1969 Rolling Stones Altamont Free Concert, as is commonly associated with the name.
Who owns Altamont Pass Wind Farm?
Altamont Pass Wind farm is a common name for a group of wind farms owned by seven different renewable energy companies.
Amongst the companies, EDF Renewables and NextEra Energy Resources are the biggest in terms of investment in the wind industry.
- Patterson Pass Wind – owned by EDF Renewables
- Summit Wind – owned by Greenbacker Renewable Energy Corporation
- Buena Vista Energy – owned by Leeward Asset Management, LLC
- Diablo Winds – owned by Huntsman Wind
- Golden Hills – owned by Golden Hills Wind, LLC
- Golden Hills North – owned by Golden Hills Interconnection Wind, LLC
- Vasco Winds – owned by Vasco Winds, LLC
Efforts of early settlers to farm the land failed due to the strong winds, which hurt the crops, but ranchers flourished. Ranch owners likewise profit from the rentals from wind turbines that occupy their land area.
How much power does the Altamont pass produce?
The seven projects in the Altamont pass have an installed capacity of 340 MW.
How many turbines are in the Altamont Pass Wind Farm?
In 2022, there will be 202 turbines in the Altamont Pass Wind farm in 7 projects. However, at one point, 6,200 turbines sprawled over the Altamont Pass Wind resource area.
Historically, between 1981 and 1987, the Altamont Pass Wind farm with two other passes installed 17,000 turbines in the ‘wind gold rush.’
What are the active wind farms in Altamont Pass Wind farm?
The following farms remain operational in the area:
- Patterson Pass Wind
- Summit Wind
- Buena Vista Energy
- Diablo Winds
- Golden Hills
- Golden Hills North
- Vasco Winds
What are the concerns with Wildlife in Altamont Pass Wind farm?
Throughout the history of the wind turbine installation in the area, the developers have received complaints from conservationists due to its effect on reducing the wildlife population of golden eagles and other bird species.
In 2007, the wind energy developers agreed to decommission 15% of all the turbines due to wildlife population concerns.
In 2015, the Golden Gate Audubon Society mounted a successful campaign against Altamont Winds Inc. (AWI). The campaign led to AWI decommissioning 828 turbines after it failed to successfully repower its wind turbine fleet.
Still, efforts and investments had been made to repower the old wind farms. Developers replaced the tightly-spaced 100 kW turbines with newer, taller turbines that decreased bird deaths.
NextEra Energy Resources and Summit Wind launched successful repowering initiatives. Newer turbines do not use the lattice-type towers anymore, giving raptors and birds an enticing place to perch. The slower-moving, larger turbines are also less prone to killing birds.