Wind Energy in Coachella Valley

Kathryn Plummer
May 27, 2018

Submitted as coursework for PH240, Stanford University, Fall 2017

Introduction

Fig. 1: Wind turbines in the San Gorgonio Pass of Southern California. (Source: Wikimedia Commons

The wind farms in the San Gorgonio Pass in the Coachella Valley are unlike any others. They include many rows stretching across over 5,500 acres of land, as seen in Fig. 1, some of which are privately owned and some of which are permitted through the Bureau of Land Management (BLM) for wind energy production. [1] As of 2008, there were more than 4,000 wind turbines sited in the area on over 40 different wind farms. [1] The combined total power was about 615 megawatts (MW). In 2016, measurements taken by the California Energy Commission showed that by with just two companies on the list from the San Gorgonio Pass, there was an estimated 300,000 MWh generated by these turbines alone. These turbines are owned and operated by multiple companies, each attaining a profit for the amount of energy that their turbines are producing. These wind farms are nestled in between two mountain ranges, the San Jacinto and San Bernadino. This allows for the cool air to pass through as hot air rises over the Coachella Valley, creating wind speeds of 15-20 miles per hour, which is ideal for these particular turbines.

Maintenance of the Turbines

Managing and maintaining these wind farms is a feat, but it continues to get harder as wind levels and direction change. On the property is a Supervisory Control and Data Acquisition Room that allows the leaders of the projects and the manufacturers to control the turbines from a distance. There are computers attached to the turbines that provide information and data regarding temperature, both outside the turbine and inside the gear oil compartment, wind speed acting on the turbine, and direction of the wind at specific moments. Members of the crew that work on the farm are responsible for the general maintenance of the turbines, which includes lubing, greasing, testing, and torquing. [2] There are also technicians that come in to repair turbines that have gone off-line, and they troubleshoot the problems. Every machine is accounted for, with log books documenting each turbine's history, allowing the manufacturers to see the input and output of each turbine. This is critical in the assembly line because there cannot be under production or over production, due to the safety hazards that may result. In order to measure the wind speeds that were previously discussed, each tower of each turbine has a meteorological component that measures actual wind speed throughout the farm in specific areas. The wind speed of the individual turbines is also kept in record through this technology. Because the wind speed is so crucial to production, this is a major development in understanding the boundaries of each turbine.

Wind Production

If the turbines capture too much wind, they will go off-line, making over production inevitable. The consequence of this is that if a turbine shuts down due to over-production, it will remain shut down until wind speeds drop below a set parameter that allows the turbines to restart. [2] This causes the farm to lose a lot of production for their manufacturers, making it of utmost importance to prevent failure instead of running turbines until they break. Stall strips can be applied to the back of the huge blades when there are seasonal changes in the lead that lead to either overproduction or underproduction. In addition to the parts that are added to the blades, there are also parts that are taken from decommissioned turbines from other parts of California to help repair active turbines.

Potential Setbacks

The Desert Renewable Energy Conservation Plan isn't supposed to impact the Coachella Valley, but local officials are worried that a wide-ranging document could inadvertently limit wind development in Palm Springs and the San Gorgonio Pass. [3] In 2015, officials wrote a plan that would lay the groundwork for wind, solar, and geothermal development over millions of acres in the California desert. There would be areas for renewable energy and then there would be zones for conservation and recreation. As of 2015, the plan's boundaries did not extend into the Coachella Valley. [3] However, there were concerns that the conservation and recreational areas along the "edges" could create insurmountable permitting requirements for nearby wind development in Palm Springs and the San Gorgonio Pass, which would then hinder the production of these wind turbines. Fred Noble, the CEO of Wintec Energy, believes that the plan would require wind companies and manufacturers to conduct studies and comply with restrictions when applying for permits to build new wind turbines in the area. [3] The result, he predicted, would be a "complete moratorium" on wind development in the area. Another potential setback is that counties don't necessarily want these turbines on their land, which is interesting because most people see California as the leader in renewable energy developments. [4] Based on recent findings, however, California has dropped to number 4 in the installed capacity for wind energy, behind Texas, Iowa, and Oklahoma. California's capacity in 2016 was measured to be 5,656 MW, which is far better than in 2008, but much less than other states are producing. The problem is that the installed capacity of California might be decreasing, based on the DOE report showing a 6 MW decrease in 2016 from 2015. Unfortunately, this decrease also includes the wind farms in the Coachella Valley.

© Kathryn Plummer. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.

References

[1] L. Berry, "Understanding Wind Farm Exposures and Managing Risks," Renewable Energy World, 2 Feb 12.

[2] D. Milborrow, "Breaking Down the Cost of Wind Turbine Maintenance," Wind Power Monthly, 15 Jun 10.

[3] S. Roth, "Desert Energy Plan Could Limit Valley Wind Development," Desert Sun, 20 Mar 15.

[4] R. Nikolewski, "Wind Energy in California: the Good News and Bad News," The San Diego Union-Tribune, 28 Aug 17.