Box 11. Case Study: West Texas Dark Sky Reserve

Box 11. Case Study: West Texas Dark Sky Reserve 

When the Permian Basin in West Texas experienced a fivefold increase in number of oil rigs, Bill Wren at the University of Texas McDonald Observatory began to educate both private companies and the public and the on the adverse effects too much light can have on a community. Lights that stay on 24 hours a day can be detrimental to organizations such as the McDonald Observatory that depend on a dark sky at night. Additionally, in places known for their beautiful night skies, too much light can mean the loss of a viewshed of great value to the community. Concerned about this potential loss, Wren has given several presentations and demonstrations to educate people about ways to enhance the efficiency of light fixtures while protecting the sky from the light pollution.

Rather than demand that companies turn off the bright lights, Wren and the McDonald Observatory have shown businesses that installing dark sky-friendly fixtures can improve light efficiency and save them money. 1 Both visibility and security are improved when measures are taken to prevent light pollution. Overall, it is estimated that $1.74 billion is wasted in the United States every year on energy for light shining directly upward. 2 By switching to shielded light fixtures for street lighting, the Canadian city of Calgary saved an estimated $1.7 million per year on energy costs. 

In an effort to help restore dark skies in West Texas, Wren reached out to Stacy Locke, the CEO of Pioneer Energy Services in San Antonio, and together they implemented a trial of new fixtures. Although Locke and Pioneer were initially unaware of the issue, once approached, they were open to implementing the changes. 3

Wren suggested that Pioneer direct their lights downward rather than horizontally, which reduces the amount of light lost into the sky. 4 Aiming the lights in this way creates a more efficient light and, saves the company money due to decreased energy costs. This change has also provided companies with a safer working environment because the downward-pointing light does not cause glare like horizontally aimed lights do. Workers are better able to see instrument controls, which creates a safer and more efficient workplace. 5 

Wren’s work has now also expanded beyond Texas, and he has collaborated with the National Park Service to develop these light managing techniques in Utah. 6 According to Wren, it is critical to educate people about the problems associated with too much light in order to implement needed changes.

Wren has also been at the forefront of the movement to create legislation to reduce lights that are adversely affecting the night sky. As a result, a light ordinance was implemented in the seven counties surrounding the Permian Basin in 2011. Each county is responsible for writing and implementing its own ordinance to reduce light pollution in that area. This legislation will prevent more light pollution linked to an increasing population as oil and gas development in West Texas continues to grow. 7

For more information, contact Bill Wren, McDonald Observatory, University of Texas at Austin at or (432) 426-3621.  


  1. Rachel Gleason, “Astronomers Look to Protect Earth’s Dark Skies,” last modified May 8, 2014.
  2. International Dark-Sky Association, “IDA Energy Brochure” (2008).
  3. Laura Petersen, “Public Lands: Drilling Boom Brings ‘Light Pollution’ to Southwest’s Pristine Night Skies,” E & E News, March 12, 2014.
  4. Petersen, “Public Lands.”
  5. Gleason, “Earth’s Dark Skies.”
  6. Petersen, “Public Lands.”
  7. Talk At Ten Interview: Bill Wren,” by Rachel Osier Lindley, Marfa Public Radio, May 24, 2012.