Wind Turbines & Birds Myth
I'll state right up front that in the past, some wind turbines
in avian flight paths did have a track record for killing birds.
In fact, bird lovers used to call these "avian Cuisinarts"
in order to get their point across.
Since around the year 2000, however, the design of utility scale
wind turbines has changed greatly with lower blade speeds and
more visibility. The assumption that wind farms are still today
killing a large number of birds has turned into a myth.
Sure, those with a political agenda of not wanting a wind farm
to go up in their neighborhood will still cite wind turbine bird
kills as if it were current fact. But, along with the few bird
strikes that do occur to turbines, the critics rarely compare
that number to the number of automobiles flying down the highways,
killing birds or the number of airline bird strikes.
The very nature of many birds is to live a haphazard and short
life. About 30-percent of all birds don't make it past their first
year of life due to collisions with different parts of nature
such as boulders, mountainsides or falling from tree branches.
In fact, older birds are commonly killed everyday by flying into
non-natural structures such as skyscrapers and the windows of
other buildings, homes, trees, electrical fences and many other
places. A typical 1.5 mW wind turbine with large surface area,
slow moving blades is more likely to receive a bird strike on
its shaft as it is on one of the blades.
The top threat to birds outside of wind turbines include the
electrical grid, vehicle collisions, buildings and residences,
communication towers, pesticides, cats, jet engines, smoke stacks
and bridges.
A study in the 1980's found that 69 millions birds migrated through
the San Gorgonio Pass near Palm Springs, California. Of this number,
only 38 bird deaths were attributed to the local wind turbines.
This means the bird mortality rate due to wind turbines in a
migratory pathway was statistically insignificant. More birds
were killed in one moment in the jetliner crash that landed safely
in New York's Hudson River than were killed over one year in the
San Gorgonio Pass in California.
The bird-o-matic myth actually started with a reality and that
is at the Altamont Pass in California where older, smaller faster
spinning turbines have been used. This one wind farm counts for
a disproportionately high number of avian deaths. Constructed
in the 1970s the Altamont Pass wind turbines contain around 4900
smaller generators that are gradually being replaced with larger,
slower bladed turbines.
Wind turbine manufacturers have responded to criticism first
by constructing larger wind generators with slower blades. They
have also experimented with different colored paints and reflective
devices to ward off birds. The sound of the turbine itself is
another early warning system to birds flying nearby.
The myth of wind turbines killing birds continues to this day.
The reality, however, is that wind turbines are a safe and clean
method to produce renewable energy and are necessary if we are
to break our addiction to foreign oil.
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