Re: [Phys-l] global temperatures -- a modest proposal

[Hugh Haskell <hhaskell@mindspring.com>]

At 00:02 -0700 04/08/2009, Bernard Cleyet wrote:
> Calculating the "wind resistance" of current ones, I think is an easy 
> engineering exercise.  The blades are made to be completely feathered 
> already?
It isn't the steady winds that I worry about. A feathered blade can 
handle a substantial wind speed. I've flown around in airplanes with 
a propeller or two feathered at speeds up to 250 knots with not 
problems. What I don't know is how well a turbine blade that may be 
as much as 30 meters long would handle gust loading that could easily 
be non-constant over that dimension, if the hub structure could be 
damaged by violent slewing as the wind gusts changed direction 
quickly.

I also worry about how well the foundation structure would withstand 
the storm surge. I heard of massive oil rigs being destroyed during 
some of the really bad storms in the North Sea, and I don't think a 
hurricane would be any easier on a wind turbine tower.

I'm sure these can be handled by competent engineers, but at some 
point the additional cost of making them strong enough to withstand a 
Category 4 or 5 hurricane may run the cost up to the "not worth the 
effort" level.

Offshore wind turbines are already significantly more expensive than 
on-shore ones, and having to replace them before their design 
lifetime due to wind damage doesn't make them any easier a sell.

Hugh
--
Hugh Haskell
mailto:hugh@ieer.org
mailto:hhaskell@mindspring,.com

So-called "global warming" is just a secret ploy by wacko 
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