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Peerie Maa
04-02-2012, 12:59 PM
This image is from the website of a company that designs instrumentation that finds applications on wind farms.
http://nanosync.files.wordpress.com/2011/03/offshore_hdt_019op.jpg
It is of Denmark's Horns Rev Wind Farm creating fog.

Any of you sail in areas prone to fog that has just had a wind farm erected?

Concordia 33
04-02-2012, 01:01 PM
This image is from the website of a company that designs instrumentation that finds applications on wind farms.
http://nanosync.files.wordpress.com/2011/03/offshore_hdt_019op.jpg
It is of Denmark's Horns Rev Wind Farm creating fog.

Any of you sail in areas prone to fog that has just had a wind farm erected?

Horseshoe Shoals in Nantucket is will known for its fog - they don't call Nantucket the Grey Lady for nothing.

Paul Pless
04-02-2012, 01:14 PM
That's remarkable! How far downwind does the fog dissipate I wonder.

Peerie Maa
04-02-2012, 01:21 PM
That's remarkable! How far downwind does the fog dissipate I wonder.
I think it could go either way.
Entire cloud scapes form from an aircraft vapour trail. The wake from those turbines might well be behaving just like a planes vapour trail.
Fog generally hangs around till the sun warms the air.

Ian McColgin
04-02-2012, 01:33 PM
This is a very famous photo by Christian Steiness showing the turbulence field behind the Horns Rev 1 offshore wind turbines. At about 1 pm on Feb 12, 08, unique meteorological conditions allowed the wind turbines to create condensation in the very humid air. This allows us to see what anyone who has sailed a boat would know anyway, that there's lots of turbulence behind a wind turbine. That's why there's such a drop-off (as much as 20%) capturable energy as you move from the weather to the lee rank of turbines in a squared wind farm. Note that the turbulence shows more how the wind's energy has become less organized. The actual removal of energy from the atmospheric system is of course quite slight, but a few times the total kilowatts generated.

Even in generally moist and foggy conditions, the ability of a windfarm to create more fog from blade-induced condensation is not something that's been much observed. So far as I know, there are no other pictures like Steiness's.

I'll be interested to sail among the windmills on Tuckernuck once the wind farm is built. It will be interesting to see if the downwind turbulence is a predictable factor, like the wind shifts and turbulence mountain lake sailors know so well, or if it's too chaotic to utilize.