Solar Power Towers Aren’t the Avian Annihilators Once Thought

Solar power towers have had a reputation as alleged avian vaporizers since preliminary reports emerged in 2014 of birds being burned in mid-air as they flew through the intense photonic flux at California’s Ivanpah solar thermal plant. Their reputation was muddied even more during tests early this year at SolarReserve’s Crescent Dunes power tower in Nevada; the solar thermal plant just recently began producing power. California public radio station KCET reported that as many as 150 birds were killed during one six-hour test in January.

It is obviously upsetting to imagine birds ignited in the name of renewable energy. (KCET reporter Chris Clarke, who has tracked the issue since BrightSource Energy began building Ivanpah in the Mojave Desert, described burning birds as “beyond the pale” in a recent article suggesting that power towers may be finished in California.)

But, upsetting as any killing of birds is, avian mortality is a downside common to many modern human creations—including buildings, highways, and powerlines. The best data on bird mortality at Ivanpah, macabre as it might be, shows the death rate to be small and likely of little ecological significance.

Meanwhile, operational adjustments at both Ivanpah and Crescent Dunes are pushing avian impacts even further below levels that could threaten local bird populations. “The data does support a low level of avian mortalities and hopefully, through adaptive management and deterrence, it will go even lower,” says Magdalena Rodriguez, a senior environmental scientist with the California Department of Fish and Wildlife. Continue reading

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Winged Creatures Should Fear CO2, Not Wind Turbines

Benjamin Sovacool agrees that wind turbines kill birds and bats, but this University of Singapore public policy professor makes a convincing case that this fact desperately needs context. Reviewing avian mortality from power generation in the June issue of Energy Policy, Sovacool shows that — gigawatt-hour for gigawatt-hour — it is fossil-fired power by a longshot that will ground winged creatures.

Sovacool’s analysis estimates avian deaths throughout the fuel cycle for coal, oil and natural-gas fired power generation:

  • Coal mining = 0.02 deaths per gigawatt-hour (GWh). For example, habitat destruction by mountaintop removal coal mining in Appalachia has killed approximately 191,722 Cerulean Warblers.
  • Plant operations = 0.07 bird deaths/GWh. Electrocution at one well-observed power plant in Spain killed 467 birds over two years.
  • Acid rain = 0.05 deaths/GWh. Cornell’s Laboratory of Ornithology estimated in 2002 that acid rain reduced the U.S. wood thrush population by 2–5%.
  • Mercury emissions = 0.06 deaths/GWh. Impacts include hampered reproduction and survival, observed in everything from albatross and woodstorks to bald eagles. Continue reading