Then and Now: 21 Years of Wind Farming in the Montezuma Hills South of Dixon

As I wrote earlier in my earlier column about the history of local irrigation, Dixon at one time was full of small, rural-style windmills used to pump water from wells for household and commercial use. For there to be so many, there had to be enough wind to make them practical. When piped water came to town, the quaint windmills disappeared, although they continued being used on farms.

Speaking of wind power, locally grown grain was carried by wind-powered sailing ships from places like the Maine Prairie landing southeast of Dixon. Elsewhere, wind power was sometimes used to grind or mill grain (creating the term “windmill”). As an aside, when I was growing up in a small town in Wisconsin, water power from a dammed-up river was used to grind grain.

With the coming of gasoline engines and electric motors, the use of wind power took a dive for many years, but people were still experimenting with it. With the hippy and self-sufficiency movement of the 1960’s, wind power was seen as a new and attractive way to generate electricity for a household.

What has provided the impetus for wind power’s fairly recent return is the desire to reduce our dependence upon fossil fuels such as oil and to reduce the global-warming effects of burning that oil (and gasoline). The state of California also was insisting that power companies generate more of their electricity from natural sources such as wind and solar. Finally, the price of traditional fuels was increasing, raising the cost of electricity to consumers. Wind, solar energy, water power and waves offer free energy sources.

One such power company was the Sacramento Municipal Utility District (SMUD). When its Rancho Seco nuclear power plant was prematurely closed down by public vote in 1989, SMUD was forced to look for new power sources. One of the new sources it looked at was wind power generation, and one of the places it looked at was the Collinsville-Montezuma Hills Wind Resources Area in Solano County, only 20 miles south of Dixon.

Sometime before then some enterprising researchers studied wind flows around California and found that the winds coming from the west through the Carquinez Strait heading into the Montezuma Hills between Rio Vista and Birds Landing were exceptional in terms of speed and duration. Also, the tops of the Montezuma Hills themselves stand between 160 and 280 feet above sea level, providing an elevation boost for more wind. The area was also attractive because it was sparsely populated and was used for non-intensive agriculture including sheep grazing and non-irrigated grain growing.   

SMUD knew that the U.S. Wind Power company had already built over 300 early-model, tower-mounted wind turbines in the area in 1989 (the Wind Power Project), and took the plunge itself, buying land in the area in the late 1980s, and installing approximately the same type of equipment in 1993. Unfortunately for SMUD, this experiment failed because the equipment had “operational challenges,” according to Jon Bertolino, SMU’s Superintendent of Renewable Generation. If you drive through the area south of Hwy. 12 today, along Montezuma Hills Road, you’ll see that none of these short, lattice-tower wind turbines are being used. Their problems also included low amounts of electricity generated, fast-turning blades more likely to hit birds, and not being high enough to catch the most wind. Today, these first-generation wind turbines are gradually being removed and replaced by larger and better turbines.

This new generation of sleek and high-up wind turbines has arrived on the scene, and you can easily see them from Hwy. 12. They have proven themselves to be much more commercially successful, and one of them can generate as much as 30 times more electricity than one of the old turbines. The new-style wind turbines also reach as high as 440 feet from the ground to the tops of the rotating blades, which themselves are 130 feet long.  

When it was found that the new giant wind turbines made money (they pay for themselves in four to five years, says Bertolino) companies were attracted just as they were years ago to newly discovered oil fields in Texas and Alaska. Besides SMUD, which now operates 52 wind turbines with an additional 55 online next near, some out-of-state companies quickly arrived on the scene.

The first company to build wind turbines in the Montezuma Hills, U.S. Wind Power, was bought by French company enXco, which made lease agreements with local landowners, and began a series of “Shiloh” wind farm projects which continue to this day. Apparently the name Shiloh was borrowed from Shiloh Road which connects Hwy. 12 with the tiny town of Birds Landing.

EnXco’s first Montezuma Hills project, completed in 2004, built 100 new-generation wind turbines, each generating 1.5 megawatts. This wind farm was then sold to Spanish energy company Iberdrola in 2007. To further cloud the picture, enXco itself was sold to PPM Energy, a subsidiary of Scottish Power. PPM Energy in 2009 completed building 75 more wind turbines in 2009 in the Shiloh II project, and has 50 more under construction in the Shiloh III project. It’s looking for county approvals for a Shiloh IV project. PPM sells its power variously to PG&E, the Modesto Irrigation District and the city of Palo Alto (which owns its own power distribution system).

You can see “There’s gold in them thar hills.”

The other major player in the Montezuma Hills is Florida Power and Light (or NextEra), whose High Wind Project began generating power in 2003 and how has 140 wind turbines of the modern, high megawatt variety. It sells its power to PPM Energy.

The Collinsville-Montezuma Hills Wind Resources Area is close to reaching the saturation point for more wind farms. Some more wind turbines can be built when the old-fashioned ones are removed. A new wind farm (the Zephyr Project) wants to build new wind turbines in the Montezuma wetlands area, but might adversely encroach on the protected Suisun Marsh.

When adding new wind turbines with new projects, companies have to pass review by a bewildering variety of county, state and federal agencies. There’s also protected tiger salamander in the hills area that companies have to pay attention to. The Federal Aviation Administration (FAA) and nearby airports (especially the Rio Vista airport) have concerns about the high turbine blades and nearby airplane flight paths. Also, the whirling blades can produce unusual radar images at Travis Air Force Base.

The birds most often killed by the turning blades (which always turn clockwise these days) are the small hawks called Kestrels, followed by red-tailed hawks, horned larks and red-winged blackbirds.

Although the Montezuma Hills area is sparsely populated, there can be complaints about the turbine’s whirling blades casting strobe-like flickering shadows on sunny days, complaints about the sounds of blades cutting through the air, and complaints about construction noise and dust. It also could happen that the novelty of windmills could wear out, and people become tired of so many whirligigs in their vicinity, similar to finding oil pumps in your downtown.

The Montezuma Hills wind farm is currently able to generate around 520 megawatts of electrical power at maximum (with 227 more megawatts of power to be added) – about equal to the Altamont wind farm further to the south. But the Tehachapi area of California, with about 1400 megawatts of capacity today (and projected to reach at least 3,000 megawatts) easily surpasses our local wind farm. A 5,000 megawatt wind farm has been proposed for South Dakota. California is now behind Texas and Iowa as the leading states for wind power generation.

There are other high-winds areas in Solano County that offer potential for wind farms. When driving Freeway 680 south of Cordelia Junction, you know that fairly constant winds buffet that area. However, due to political, esthetic and land ownership considerations, that area isn’t open to wind farming at this time. Another area is at the top of the Vaca mountains ridge where antenna farms are the main occupants these days. The problem with building wind turbines up there is getting all the materials up there – the 130-foot-long blades, for example. Finally, the Potrero Hills near Suisun City offer possibilities.

I calculate that two of the giant wind turbines in the Montezuma Hills (those which generate three megawatts) could supply all the electricity needed by all the homes in Dixon. Of course, you couldn’t hook them up directly, because sometimes there isn’t enough wind to power the wind turbines.

A few further factoids: On the new-generation wind turbines, the blades make complete rotations around every three to six seconds. New-generation wind turbines can’t handle really high winds and will automatically brake and close down when winds reach approximately 60 miles per hour. Initially, the turbines generate high-voltage direct current, but that’s changed to alternating current within each turbine’s hub, or nacelle. Wind-power companies, to see if a new wind turbine installation is merited, do wind testing by installing a high, slender test-tower which measures and records airspeed at various elevations at all times of the day.

Some of the happiest people around must be the landowners who receive lease payments from the wind-power companies for siting the wind turbines on their land. As long as that wind keeps blowing strong, the money will keep coming in. And not only that, the land underneath the turning blades continues to be used for animal grazing and raising grain.