Re: Food for Thought--Seaward Wind Farms

Hi Bob, I think that somehow your wake effect numbers got very
distorted. For nearly 25 years, I raced sailboats with a passion. Years
ago, I remember reading a book on weather and it's impact on sailboat
racing. In that book, the author said the effects of an objects wind
shadow extened for 9-10 times the height of the object. The effect was
cone shaped where there was a large impact in the immediate lee of the
object and the width, height and velocity of the impact diminished in a
cone shape, the farther you get from the object. So, say your wind
shadow creator is a 100' tall tree. Wind downwind of the tree would
show signs of disturbance for about 1000' feet from the tree. Beyond
that, no noticable effect. Now, consider the windmill with 90' blades.
If the hub is 200 feet above the water the height is close to 300 feet.
The wind shadow or wake effect would extend about 3000 feet. That
makes a lot more sense than the 3.7 miles you mention. I'm not trying
to find fault, just trying to look at the issue logically to find
truth.

As someone mentioned earlier, the effect on the wind should be no more
than the impact of planting a row of tall trees. Half a mile away, you
can't even tell.

For those concerned about bird deaths, it seems logical that most bird
deaths occur when birds fly into pencil thin guy wires holding up
radio and transmission towers. The birds have a hard time seeing them
and don't expect to find obstacles 500 feet above the ground, flying
along at 50 mph. Wind turbines don't have guy wires. And being placed
10 miles off the coast should not impact migratory paths. Migratory
birds tend to fly along the coast because it provides reasonably safe
places in the laguna's and wetlands to stop, rest, and feed. I could be
wrong, but I'm not sure if there are that many birds which have long
over-water crossings, like from Cancun to Corpus Christi, on their
migratory routes. Seems too strenuous for most species.

.

Relevant Pages

  • Re: Food for Thought--Seaward Wind Farms
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