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Windmill

Kayak Jack

Well-Known Member
Aug 26, 2003
12,845
52
80
Okemos / East Lansing Michigan
#2
Thanks, Darrel. I've always liked the looks of a windmill, particularly if it's all still there. A derelict mill - one with parts missing and inoperable - is a sad relic.

New wind generators seem to lack a lot of blades. They turn slowly, and there is a lot of circular area unattended. I realize that a slide rule somewhere said that is the most efficient way to do it. I don't believe it. For a prop rotating near the Mach at tip speed yes, but not for one doing only 5-8 RPM.
 

Kayak Jack

Well-Known Member
Aug 26, 2003
12,845
52
80
Okemos / East Lansing Michigan
#4
Neat. I hate a dry camp. In camps maintained by Michigan DNR, counties, townships, etc., there is often a hand pump for water. I still run that through my purifier before I drink it. OK for dishes of a bath, though.

I wrap paper coffee filters around the intake gizmo on the end of the tube. Saves putting gunk into an expensive filter/purifier element. After pumping 3-4 quarts of water, there's gunk of various colors clogging the outside of the paper filter. Water comes out of my First Need purifier tasteless. (BUT - I still wouldn't mix it with single malt scotch. Scotch greatly improves the flavor of water, like when addding salt to beer - beer improves the flavor of salt.)
 

tx river rat

Well-Known Member
Feb 23, 2007
3,043
2
Waco Tx
#5
Jack
Those props on the windmills down here are 180 ft in a decent wind you would be surprised what the tip speed it.
Another reason for just three blades is wind load,if you made a blade like the windmill 180 ft tall you couldnt drill a hole deep enough for the tower to stand a 70 mile an hour wind,even the single blades have to be furled are the will self destruct.
Ron
 

gbinga

Well-Known Member
Nov 7, 2008
736
2
Hoschton, GA
#7
Seems like I read somewhere that the big blade at a slower RPM is safer for the birds - ? Apparently the big power generating mills kill a lot of birds. Used to see smaller props turning faster, but the newer ones seem to all be what ya'll are describing - huge twin blade prop, turning slow.

GBinGA
 

Wannabe

Well-Known Member
Apr 5, 2007
2,631
1
on the bank of Trinity Bay
#10
Jack,
You are right about the birds. They won't go near them. The blade tip velocities are no where near the speed of sound though they are hauling it around at a pretty good clip. The blade tips are designed to minimize blade tip vortices (like wing tip vortices) but they still exist. These vorticies are constant but we are unaware of them. They set up a harmonic pattern that cannot be felt or heard by the human ear but birds are very sensitive to them.
The harmonics irritate the birds to the extent that they give the windmills a wide birth. That is why you don't find dead birds around windmills.
Bob :? :wink:
 

Kayak Jack

Well-Known Member
Aug 26, 2003
12,845
52
80
Okemos / East Lansing Michigan
#11
Birds sensing minor pulses in air pressure sound similar to sharks sensing minor changes in water pressure, or electrical fields emanated by potential prey.

I've read that when people go overboard in the ocean, dolphins will sometimes gather and scan them. They will gather closely around a pregnant woman, and protect her. I don't know if it's true or not, but I would readily believe it.

My time and experience outdoors is similar to that of many on here. And, of course, dissimilar in some ways too. But many of us have mentioned experiences where it was pretty evident what animals were thinking.
 

gbinga

Well-Known Member
Nov 7, 2008
736
2
Hoschton, GA
#12
As a matter of fact there is an article in USA Today (today's issue, page 3A) "Bird Deaths soar at wind farms".

Altamont Pass, in the San Joaquin Valley in California, has 5400 windmills producing electricity. Around 10,000 birds per year are getting killed, including eagles and hawks, and owls. There is concern that if we try to accomplish the goal of producing 20% of our electricity by wind power by 2030, raptor extinctions may result.

I don't have a whole lot of knowledge on this, or a strong opinion, but I've read enough different articles to think that it is a recognized problem, not a myth.

Nuclear power doesn't kill very many animals, that I know of. Or people, either. As a matter of fact, the casualties are just about zero, if you ignore Chernobyl (nitwit mistakes made with inferior technology). Enviromentalist types need to reevaluate their position on nuclear power.

gbinga
 

Wannabe

Well-Known Member
Apr 5, 2007
2,631
1
on the bank of Trinity Bay
#13
George,
Are you sure of those facts. Your facts fly right in the face of what a Professor of Bird (or is that boat) Science from the University of Anahuac told me. Imagine that. :mrgreen:
Bob :? :wink:
Never mind! I see those are California birds.
 

Kayak Jack

Well-Known Member
Aug 26, 2003
12,845
52
80
Okemos / East Lansing Michigan
#14
Sadly, it seems that many stories, research reports, etc. that are related to "environmentalists" are often rebutted.

Oddly enough, I know not a single outdoorsman - we who hunt, hike, camp, paddle the outdoors since childhood - who considers himself a tree hugging environmentalist. Only those from the city who digested Bambi - and thought it was real.
 

gbinga

Well-Known Member
Nov 7, 2008
736
2
Hoschton, GA
#16
No, I'm not sure of the facts. Nor are they mine. Just telling you what I read in an article in USA Today. Could be they just made it all up. Could be a liberal media conspiracy to undermine the wind power industry.

George
 

gbinga

Well-Known Member
Nov 7, 2008
736
2
Hoschton, GA
#17
A google search of "bird deaths wind power" produces links to articles speaking to both sides of the issue.

Wind farm location seems to make a difference. So does newer technology (bigger slower props, less of them) vs. older technology (smaller, higher RPM, more turbines in a given location).

From what I can tell, the University of Anahuac is located in Mexico City. The Mexican government has a pretty big commitment to wind power.

Imagine that.

GBinGA
 

Kayak Jack

Well-Known Member
Aug 26, 2003
12,845
52
80
Okemos / East Lansing Michigan
#18
Makes one wonder why birds never committed suicide by flying into the old, farm windmills. They have lots of blades and turn rapidly.

I'm sure that some birds have perished in windmills. They also perish by running into cars, airplanes, and windows. Do tree huggers have resultant campaigns there? If not, they seem either hypocritical, or merely poorly informed?
 

gbinga

Well-Known Member
Nov 7, 2008
736
2
Hoschton, GA
#19
Kayak Jack said:
Makes one wonder why birds never committed suicide by flying into the old, farm windmills. They have lots of blades and turn rapidly.

I'm sure that some birds have perished in windmills. They also perish by running into cars, airplanes, and windows. Do tree huggers have resultant campaigns there? If not, they seem either hypocritical, or merely poorly informed?
That's a good question. Maybe the old, multiple blade windmills were more visible? Perhaps noisier than the new ones? Smaller than the commercial rigs we put up now?

As to cars, planes, feral cats, windows and such, yes, that seems to be a valid point, and it is also exactly what the wind power proponents point out.

As to tree huggers, it seems clear that the really serious ones would love to do away with cars, airplanes, windows, and people for that matter.

gbinga
 

Wannabe

Well-Known Member
Apr 5, 2007
2,631
1
on the bank of Trinity Bay
#20
Ginga,
It is my belief that tree huggers do not want to do away with humans. By their vary nature they want, no- need humans around so they will have someone for them to dictate to what they can or cannot do. Tree Huggers would probally be satisifyed reverting us all back to the Stone Age. MABY
Bob

PS After a moments thought about this I beleive we might be in the wrong section for this subject. It is way too easy to be sidetracked.