John Metcalfe
John Metcalfe was CityLab’s Bay Area bureau chief, covering climate change and the science of cities.
The Ivanpah Solar Electric Generating System is a massive energy installation in the Mojave Desert about 50 miles southwest of Las Vegas. Seen from above, it looks like a futuristic temple built by sun-worshiping Andromedans:
A top-down view reveals vast, concentric circles made from some of the facility’s 170,000-plus heliostats:
These mirrored panels use software to track the sun and reflect its brilliancy at three central, 459-tall solar receivers. At the tops of these towers the energy is concentrated to a ferocious degree—surface temperatures can soar above 900 Fahrenheit—turning water into steam, generating electricity, and channeling it toward thousands of California homes.
Opened in 2014, Ivanpah is the biggest solar thermal power plant on earth and a promising beacon for advocates of green energy. (Though some argue the $2.2 billion project isn’t doing as well as promised.) It’s also slaying a lot of wildlife. An environmental report based on carcasses littering the ground estimated that, in its inaugural year, the facility killed more than 3,500 birds. The major problems: Animals crash into the heliostats or get too close to the solar receivers and are scorched, leaving smoke trails in the sky as they flap away.
Now we can see what that looks like, thanks to scientists at the U.S. Geological Survey who monitored the plant for two weeks in 2014. Their goal, they write in PLOS ONE, was to develop new ways to detect animals entering solar danger zones, not to count the dead. Still, they did notice scores of insects going up in white puffs. They also recorded 14 birds “flashing” or “smoking” and then flying away, their health conditions unknown.
Here’s one video they made showing “small smoking objects (insects) and a larger object (bird) as it begins to smoke when entering the solar flux.” The light-blue inset is a thermal recording of the same event:
Another shows smoking insects as well as birds coasting above the towers, sometimes leaving dark trails. “It was sometimes unclear whether larger birds flying above the tower were being affected by flux and smoking,” the researchers write, “or whether ‘video ghosting’ accounted for visual trails we occasionally observed behind birds in the recorded imagery.”
The researchers hope their observations will be used to wildlife’s benefit, as more solar facilities go up in the Southwest and elsewhere. Here’s more from a USGS press release:
“Our goal of this pilot study was to evaluate several surveillance methods, determine their benefits and limitations, and assess whether they would be appropriate for future use to study potential impacts of solar towers on flying animals,” said Robb Diehl, USGS research ecologist and lead author of the study….
More extensive research could test the utility of these technologies to automatically detect and observe flying animals near solar towers to advance understanding about their effects on wildlife.