"Mark Fischer" <> wrote:
>
> The ones at Altamont are the high-speed turbines that have been in the
> news because of bird strikes. These are giant, slow-turning turbines
> that do not have that issue.
As an aside people might want to know that that most turbines rotate a constant
RPM
regardless of wind speed and that most bat mortality in the few studies that
have been
conducted occur at low wind speeds (below 5m/s) These speeds are close to the
'cut-in
speed, roughly the wind speed at which economic power generation starts with
the current
turbine designs. One engineering goal is to lower the cut-in speed.
Altamont is notable for raptor kills, particularly golden eagles, but there is
a high level of
concern among scientists and some wildlife managers about mortality of
migrating bats
with the extensive turbine buildout proposed in many areas, rapidly increasing
rotor
diameter and rotor swept area. The wakeup call came from large kills of several
species at
a new installation on an Appalachian forested ridgetop in West Virginia, but
there have
been more recent similar surprises from the Canadian plains. Limited sampling
has shown
some bat kill in the Montezuma Hills.
In the audio realm there is an NPR story on this topic:
http://www.loe.org/shows/shows.htm?programID=07-P13-00019
A recent congressional committee hearing in Washington on this issue was
titled "Gone
with the Wind: Impacts of Wind Turbines on Birds and Bats" In response to the
evidence,
Nick Rahall from West Virginia has proposed legislation to address issues of
wildlife
impact from nominally 'green' energy.
Bill R.
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