The city and residents of Longmont are obviously committed to wildlife preservation. The city’s wildlife management plan is an evidence of that commitment. Special attention is given to the protection of the bird population. The plan includes a specific raptor nest monitoring and protection program. Emphasis is placed on the safety of migratory birds but all birds are valued. And undoubtedly this concern for wildlife also extends to bats. Bats control insects, especially mosquitoes. And some bats also serve as pollinators and seed dispersers. This is what makes it so puzzling that there doesn’t seem to be any concern by the Longmont leaders and residents endorsing the Longmont power provider’s plan to go to 75 percent renewable energy by 2030; even though it includes adding a large amount of wind power that is a significant threat to birds and bats.
This is especially true for migratory birds and raptors. The problem of wind turbine bird kills has long been recognized, leading to them being termed “the Cuisinarts of the air” as far back as 1990. Although turbine rotational speeds are rather low, the long blades result in tip speeds exceeding 200 mph in modern designs. This makes collisions between the turbine blades and any birds in the area almost inevitable, and the birds rarely survive the collisions. As noted, raptors appear to be particularly susceptible. It has been theorized that this may be due to their visual adaptions for hunting which gives them a large blind spot directly in front of them. But in any event, wind turbines are a menace to birds of all types.
The American Bird Conservancy has stated that the annual loss of birds in the U.S. from wind turbines is estimated to have been as high as 573,000 in 2012 when wind power production was only about 3.5 percent. It is now up to about 7 percent so we are probably losing over a million birds a year to them. And, Department of Energy projections indicate up to 5 million birds could be killed annually if wind produced power should ever reach 35 percent.
It also has been known for years that wind farms kill bats, just as they kill birds. But since echo-locating bats detect moving objects better than stationary ones, researchers have been perplexed by this, thinking the bats should be able to detect and avoid the fast-moving blades. Then it was found that most of the dead bats showed no injuries consistent with having been struck by the blades. Dissection revealed the bats had been killed by burst blood vessels in their lungs, suggesting that the air pressure difference created by the spinning blades had terminated them, not direct contact with the blades. This makes the turbines extremely hazardous to bats as is borne out by the number of fatalities. According to a study published in December 2013 in BioScience, a researcher at the University of Colorado Denver found that more than 600,000 bats might have died as a result of interactions with wind turbines in the U.S. in 2012 alone. Another study published in May 2017 in Biological Conservation found that wind energy could pose a substantial threat to all migratory bats in North America. The study showed that mortality from wind turbines could drastically reduce population size and even risk the extinction of certain bat species.
In announcing its plan to go “net zero’ on carbon emissions by 2030, the Platte River Power Authority, Longmont’s power provider, stated the plan would require 350 megawatts additional wind power, apparently this is in addition to the 78 megawatts of wind power PRPA currently contracts for and the 150 megawatts scheduled to come on line in 2020, a total of 578 megawatts capacity, requiring almost 300 individual wind turbines. The wind farms supplying the present 78 megawatts and the 150 megawatts to go on line in 2020 are mostly scattered across southern Wyoming plus some in the northeastern corner of Colorado near the town of Peetz. Probably the units for the additional 350 megawatts will be located in similar areas far from the communities served by PRPA. I hope this isn’t a “nimby” issue for Longmont residents; i.e., as long as the dead birds and bats don’t fall near them, they can’t be bothered.
Carl Brady is a retired engineer who has been a resident of Frederick about 13 years
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