An array of 300,000 mirrors covering 3,500 acres focus the sun’s rays on three 460-foot towers. The towers contain a liquid that, when heated, powers steam turbines. Those turbines in turn produce enough electricity for about 140,000 homes, without greenhouse gases or other emissions.
What no one seems to have counted on was how the facility, developed by BrightSource Energy Inc., would affect the environment. We now know the answer: It attracts birds and kills them.
How it happens: First, insects are drawn to the reflective light of the solar mirrors. That draws small, insect-eating birds, which in turn draw larger predatory birds. The rays of the mirrors’ reflected light produces temperatures from 800 degrees to 1,000 degrees Fahrenheit. Any animal caught in the intense glare of the mirror’s rays may catch fire and plummet toward the ground, or spontaneously combust altogether.
The report has found that at least 141 birds have died at the Ivanpah facility. This sort of statistic is bad news for sustainable-energy advocates, who often weather attacks from conservatives that wind turbines kill birds, too. A survey of scientific literature put turbine-related bird deaths at somewhere between 140,000 and 328,000 each year.
But it’s worth keeping these numbers in perspective. In the six months after the BP oil spill in 2010—when 4.9 million barrels of crude oil leaked into the Gulf of Mexico—more than 7,000 birds were collected in the spill area, and more than 3,000 were coated in oil, according to the National Wildlife Federation. Up to 23,000 birds could have been killed by the spill, according to an estimate in Audubon Magazine. It’s also estimated that 225,000 birds died from the Exxon Valdez spill in 1989.
No matter what form it takes—wind, solar, or oil—energy harvesting rarely benefits our avian friends. Even deep underground, birds can become energy casualties—just look at the canary in the coal mine.