* * *

Ice Throw Endangers Motorists

"Oops." | Ice Throw
Ice Throw Endangers Motorists

(Translated from German)

For Friday the air temperature is continuously under 3 °C and the humidity also over 90% measured. Thus definitely all conditions for ice throw were present.

I found the ice breaking into chunks up to 80 m distance from the rotor masts.

One of the photos shows fragments lying close within the proximity to a public road, smaller ice fragments lay on the road "Lammersstiege".

Ingrid Koopmann made the photos.

At present it is 19:00 o'clock; since 17:00 o'clock the windraeder has run despite substantial ice throw danger again.

Josef Koopmann

Just my addition to this

Just my addition to this story: the danger is not from the ice hitting the motorists ... the danger is from the cars hitting the ice chunks left in the road. This causes an auto accident. From 1995 to 2005 there have been 73 reported ice throw accidents.

An 80 meter throw? That

An 80 meter throw? That converts to 262 feet. The setback requirements for New York - at 1000 feet or 1200 feet. Effie - just what is your point? That the area that report is based on should have enforced a larger 1000ft setback distance?

Actually, a couple of German

Actually, a couple of German engineers figured out an appropriate formula for determining ice throw. I wrote a detailed analysis AT THIS LINK.

Basically, ice throw can be calculated as d = (D + H) * 1.5 where D is the rotor diameter and H is the hub height. Adding a 10% margin for topography, you get d = (D+H) * 1.6.

The proposed Bethany setbacks would be about 941ft.

As you mentioned, setbacks from homes have been about as much -- this is good. HOWEVER, I have not seen any town (other than Bethany) considering this setback from roadways, active rail lines, snowmobile trails, other public right-of-ways and overhead utility lines.

The primary danger from ice throw is to vehicular traffic and flimsy structures like overhead power lines. These are not being protected in New York state.

Where in this equation is

Where in this equation is the factor for wind drag? HMM. Absent I see. One of the german studies that you pointed me to have a max throw of 120 meters as measured over a 20 year period. Not even close to the setback. Red Herring.

Good God, will you READ the

Good God, will you READ the damn posts????? There IS no wind drag in this formula. It is not a theoretical formula of how far ice can travel based on physics. What the German scientists DID was to go out and measure the distance between turbines and ACTUAL ICE PIECES which came off them. Then, they devised a formula which fit reality.

I'm having a really difficult time not using sailor's language here. Argue if you must ... that's GOOD. Refuse to actually READ the linked posts and then call everything a red herring and you're nothing more than a pain in the ass for people on both sides.

So how about you going back

So how about you going back and actually reading the article yourself and then tell us just how far was the max. measured throw as recorded over a 20 year interval of time? Its in there.

The article to which I

The article to which I linked is one that I wrote myself. I think I read it at some point.

Ok. I think I made my point

Ok. I think I made my point and I'll quiet down as you know then the contradiction between your desire on having a 1/2 mile setback verus the largest measured distance and what the formula yields. Plus referencing yourself as backup material is well... a bit self serving? I've said enough. Thanks for your patience.