JUDY WOODRUFF: But, first, we turn to the topic of wind power. It’s the country’s fastest growing energy source, expected to triple by 2040.
But the giant wind turbines can also pose a threat to wildlife. Thousands of birds are killed each year when they run into turbines or are hit by their blades. Now scientists at one of the nation’s oldest wind farms have developed a strategy to help save protected species.
Our colleagues at public TV station KQED in San Francisco bring you this story produced by Gabriela Quiros and narrated by Scott Shafer.
SCOTT SHAFER: The Altamont Pass, east of San Francisco, is home to hundreds of bird species. They hunt and play in the midst of 3,000 wind turbines, which can be deadly, especially to golden eagles.
MAN: There’s an eagle right there.
MAN: Eagle, eagle, eagle, eagle, eagle.
MAN: Right here flying below…
MAN: OK, below the horizon.
SCOTT SHAFER: Biologists Doug Bell, Shawn Smallwood and Joe DiDonato study golden eagles.
MAN: We have got some good wind going today, so this might be a good day for seeing a few eagles.
DOUG BELL, East Bay Regional Park District: The Altamont Pass Wind Resource Area is within and adjacent to one of the densest nesting populations of golden eagles in the world.
SCOTT SHAFER: Golden eagles are protected under federal law. According to county estimates, 35 golden eagles were killed by the Altamont’s turbines in 2013.
DOUG BELL: Their population is going down the drain. The Altamont is killing more eagles than the local population can reproduce.
KRYSTA ROGERS, California Department of Fish and Wildlife: The primary injury on this bird is the left wing. The carpal bone is shattered.
SCOTT SHAFER: Today, Krysta Rogers of the California Department of Fish and Wildlife Examines a golden eagle that was found injured on an Altamont Pass wind farm. The bird had to be euthanized.
KRYSTA ROGERS: We describe this as blunt-force trauma, which is consistent with a wind turbine strike, given the location where the bird was found.
MAN: The transmitter is going to stay on here about three years.
SCOTT SHAFER: The dead golden eagle was one of 18 that researchers had been tracking. Though four of them have died after hitting turbines, scientists were still able to recover valuable data.
DOUG BELL: One of the more valuable things that we have learned from our transmitters that we placed on eagles is that they use the Altamont a lot. They go in and out throughout the course of the year. They will spend weeks at a time there.
SCOTT SHAFER: For more than a decade, environmental groups have been trying to get wind companies to protect birds in this area, says the Audubon Society’s Michael Lynes.
MICHAEL LYNES, Audubon California: The Altamont was sort of seen as a black eye for renewable energy, because any time someone was proposing a new wind farm, it would raise the specter of the Altamont Pass.
SCOTT SHAFER: After chapters of the Audubon Society and other environmental groups sued to get birds protected, wind companies agreed to take down old wind turbines.
MICHAEL LYNES: We wanted to move towards getting the old turbines out of the Altamont Pass because, in a process called repowering, up to 30 old turbines can be replaced with one single new turbine, which then results usually in significantly less bird mortality.
SCOTT SHAFER: At this wind farm, 300 turbines are coming down and being replaced by only 10 new ones, which together will produce double the amount of electricity, enough to power 12,000 homes for a year.
RICK MILLER, EDF Renewable Energy: It’s time to pull the old machines down and put new ones up.
SCOTT SHAFER: Rick Miller of EDF Renewable Energy, which owns the wind farm, says the repowering process will cost $35 million and is facilitated by federal tax credits for wind energy.
RICK MILLER: The turbines are becoming much larger, much larger rotor diameters and much taller towers. So we have really been able to reduce the number of turbines required to produce a tremendous amount of energy from the same site.
SCOTT SHAFER: And that means there are fewer turbines for birds to hit. Companies can also place the turbines more strategically.
SHAWN SMALLWOOD, Ecologist: Three hundred meters above ground.
SCOTT SHAFER: Ecologist Shawn Smallwood advises companies on where to put their turbines to minimize bird deaths.
SHAWN SMALLWOOD: This is where the old turbines were, and this is also where the burrowing owls nest. And so the fatality rate was pretty high.
SCOTT SHAFER: This wind farm was one of the first to get new, more efficient turbines.
SHAWN SMALLWOOD: When we repower, we put the new turbines up on the top of the hill, where the burrowing owls are not. So, our burrowing owl fatality rate dropped to zero in three years of monitoring, and that’s why.
SCOTT SHAFER: Smallwood says that when wind energy companies first installed over 7,000 turbines in the Altamont Pass in the 1980s, they gave little consideration to bird safety.
SHAWN SMALLWOOD: Those are the most dangerous turbines in the Altamont Pass on record. There’s one 120-kilowatt turbine down there, now removed, but it’s on record as having killed one eagle per year for 10 years. And the reason is because there’s a lot of eagle traffic through the lowest spots of the Altamont Pass.
SCOTT SHAFER: Birds fly lower in some areas to avoid wind resistance and to hunt for prey. But, with their keen eyesight focused on the ground, eagles might not see a wind turbine blade until it’s too late.
SHAWN SMALLWOOD: Social interactions are very important. So, an eagle responding to other eagles, chase each other around or chase some other birds, these are dangerous social interactions that lead up to what we call events, near-misses.
SCOTT SHAFER: The federal government is increasing enforcement of laws aimed at protecting golden eagles, including bringing criminal charges against two companies whose turbines killed golden eagles in Wyoming.
Scott Flaherty of the U.S. Fish and Wildlife Service says that was a significant step.
SCOTT FLAHERTY, U.S. Fish and Wildlife Service: The prosecution of those two companies certainly sent a message to companies across the country there is incentive there to come in and work with us.
SCOTT SHAFER: That incentive is a new permitting system that allows companies to kill a limited number of eagles each year. Even the Audubon Society’s Michael Lynes sees permits as a positive step.
MICHAEL LYNES: Before, it was sort of chaos. There was no real regulation. There was no real enforcement. And we know birds were getting killed in large numbers. Now we can actually keep track of that. We can hold people accountable, and we can take steps to remedy the problem.
SCOTT SHAFER: As the U.S. increases its wind power capability, scientists, including Shawn Smallwood, believe fewer turbines and better placement are key to protecting wildlife.
SHAWN SMALLWOOD: We have learned a lot here. And so it should be the number one laboratory in the country for learning what not to do wrong with wind development around the rest of the country.
SCOTT SHAFER: For the PBS NewsHour, I’m Scott Shafer.