Of Birds, Bats and Blades

The wind energy industry faces multiple challenges in California.

Flocks of birds near wind turbines in Solano County. (Photo: Craig Miller)

It’s hard to find people who are just flat out against wind energy. As with real estate, attitudes seem to come down to location, location, location. That’s why three of the thorniest issues with wind are project siting, transmission (lines for the power produced), and the industry’s turbulent history with birds and bats. Some of those challenges are highlighted in this slide show, designed to accompany my two-part radio series.

Last fall, even the National Audubon Society, one of the nation’s most stalwart protectors of winged creatures, published a position statement generally favorable toward wind power, calling it a “good news, bad news” proposition. The statement calls California’s Altamont Pass “notorious for killing many raptors, including golden eagles.” A 2003 study by the National Renewable Energy Lab calculated that on average, each turbine in the pass was claiming a bird about once every five years (0.19 birds/turbine/year) — but there are thousands of turbines in the pass, many older models that are more of a danger to birds.

Developers are in the process of “repowering” the pass with newer, larger turbines, less lethal to birds. That may seem counterintuitive but the older, smaller models caused more problems. Since they had lower output, more of them were required. The blades were positioned lower, spun faster, and supported by lattice towers that provided inviting nesting spots, unlike the smooth tubular towers of new turbines.

Altamont is the oldest of California’s four biggest wind energy zones, highlighted on this interactive map.


View Major Wind Energy Pockets in California in a larger map

The Audubon statement concedes that newer turbine designs are becoming more bird-friendly, and finds climate change a bigger threat to avian critters in the long run. The Society went on to call for an extension of the federal Production Tax Credit for wind development, fearing its expiration next year encourages wind developers to rush projects along and “cut corners” on siting.

Meanwhile industry and wildlife groups have joined forces to address the bat mortality issue.

Hear my two-part radio series on challenges facing wind energy development in California on The California Report. Those and all other stories in our series, “33 x 20: California’s Clean Power Countdown,” are archived at our special series page.