What about Wind Turbine with Blade Guards to protect birds?

burraak

I was wondering why noone ever installed some kind of blade guards to protect poor birds? is this because of any amount of wind blockage? or high cost? whatever it is but small compromises are better to save birds life .........
I searched the web there are designs in discussion for so called "Birds friendly wind turbine" but what about already installed turbines???
Therefore my confusion/question is why can't we install such blade guards on domestic or industrial turbines?

froggersix

this doesn't happen. turbines don't turn blades to make wind like fans do the wind turns the blades so if the blades are moving at dangerous speeds so is the wind. they don't spin fast enough to chop up sparrows.

burraak

froggersix wrote: »

this doesn't happen. turbines don't turn blades to make wind like fans do the wind turns the blades so if the blades are moving at dangerous speeds so is the wind. they don't spin fast enough to chop up sparrows.

It happens a lot and Speed doesn't matter Youtube is full of such accidents where slow moving bird hit slow moving blade

Thom

I bet u have killed more birds with your car in one year then my 2 windmills have in 30 years. U may not drive a car. I haven't found dead birds under my windmill . I wonder what the number one man made threat is for birds ? Could b fossil fuel related . Tar sands oil,coal. I try not to use much of that.

Thom

burraak

Thom wrote: »

I bet u have killed more birds with your car in one year then my 2 windmills have in 30 years.

Thom

I was reading an article the other day where writer was trying to prove that cat kills more birds than human hunting but its not about the ratio my friend ...

BB.

The short answer is that you will never see large wind turbines with screens on them... The screens are big and heavy (have to self support on across 10's to 100's of feet). And the issue of reducing airflow do to the screen would be a big issue too... Aircraft jet engines do not like to suck in birds either--And nobody has made screens for them either (there are optionally installed when needed sand screens for helicopter turbo jet engines--But not for their rotors.

There have been some other designs trying to capture wind energy that don't use rotating blades--But so far, those seem to be mostly in the paper design and small mockup stage at this time.

Search Google for "bird friendly turbines" and click on the IMAGES search for some ideas.

-Bill

burraak

BB. wrote: »

The short answer is that you will never see large wind turbines with screens on them... The screens are big and heavy (have to self support on across 10's to 100's of feet). And the issue of reducing airflow do to the screen would be a big issue too... Aircraft jet engines do not like to suck in birds either--And nobody has made screens for them either (there are optionally installed when needed sand screens for helicopter turbo jet engines--But not for their rotors.

There have been some other designs trying to capture wind energy that don't use rotating blades--But so far, those seem to be mostly in the paper design and small mockup stage at this time.

Search Google for "bird friendly turbines" and click on the IMAGES search for some ideas.

-Bill

Aircraft/helicopters simply doesn't come into debate they are not airborn 24/7 .......
I have already mentioned those bird friendly designs and my concern i.e if those bird friendly design ever materialized what about already installed 3 blade turbines noone is going to replace them ......
As for the air flow no study ever carried out that how much blade guards would reduce effeciency
As for the size I don't think it is much of an issue either

BB.

But if you notice... the size of the grid on the fan in the park is large enough to let most bird through--Or at least, not safely stop the birds. And what good is a safety grid if the birds still break a wing.

As for commercial aircraft (airliners)--They are in the air for >12 hours per day for the big guys. Of course, a jetliner is above the birds except for takeoffs and landings. But since the most dangerous part of the flight is take offs and lands, protecting against bird strikes is important.

But most airliners are designed with redundancies (multiple engines, capability to withstand a single bird strike and make a go-around/emergency landing. I heard (don't know if it is true) that only one airliner has actually been brought down by (multiple) bird strikes (in the US? Hudson River US Airways).

Anyway--There are a lot of aerodynamic (laminar airflow issues for blades, disturbed airflow by "screen", shapes of "screen" will have wildly different drag coefficients, drag affecting stresses on structure, mass of screen affects on structure/bearings/servicing/tower design) and structural (for every 2x the length of a beam, the stresses go up by 4x)

Attachment not found.

And note that the Coefficient of drag goes with the square of the wind velocity;.. You get a good size storm out there, and 4x normal wind flow becomes 16x the structural drag.

I am not saying that something cannot be done--But to date using standard HAWT (horizontal axis wind turbine) designs--I have not seen anyone do it successfully on any meaningful scale.

This stuff is not a trivial design exercise:

From this thread: Large Windmill collapse in NH; AntronX posted this shot:



-Bill

burraak

BB. wrote: »

But if you notice... the size of the grid on the fan in the park is large enough to let most bird through--Or at least, not safely stop the birds. And what good is a safety grid if the birds still break a wing.

As for commercial aircraft (airliners)--They are in the air for >12 hours per day for the big guys. Of course, a jetliner is above the birds except for takeoffs and landings. But since the most dangerous part of the flight is take offs and lands, protecting against bird strikes is important.

But most airliners are designed with redundancies (multiple engines, capability to withstand a single bird strike and make a go-around/emergency landing. I heard (don't know if it is true) that only one airliner has actually been brought down by (multiple) bird strikes (in the US? Hudson River US Airways).

Anyway--There are a lot of aerodynamic (laminar airflow issues for blades, disturbed airflow by "screen", shapes of "screen" will have wildly different drag coefficients, drag affecting stresses on structure, mass of screen affects on structure/bearings/servicing/tower design) and structural (for every 2x the length of a beam, the stresses go up by 4x)

Attachment not found.

And note that the Coefficient of drag goes with the square of the wind velocity;.. You get a good size storm out there, and 4x normal wind flow becomes 16x the structural drag.

I am not saying that something cannot be done--But to date using standard HAWT (horizontal axis wind turbine) designs--I have not seen anyone do it successfully on any meaningful scale.

This stuff is not a trivial design exercise:

From this thread: Large Windmill collapse in NH; AntronX posted this shot:



-Bill

I presented the image above for the concerns you mentioned regarding grill size,base and weight not the actual or final design of space in betwean,
Aircrafts,cats,hunters,cars and other bird related hazards are not my concern I'm sure some other guys are definitly worrying about that ......
So lets discuss something about hundereds and thousends of birds crushing wind mills......
I'm sure Aerodynamic laws are even more complex and detailed what you tried to explain above
and your concerns are just concerns like any new upgrades or changes in a product there are parameters,issues, compromises and trade offs but when something is decided to be done there are definitly way outs

Doing it is another thing first someone should look into the issue and do some lab tests and calculations only then there could be some logical explanation ,
So far it seems no one is interested to solve this issue

BB.

For me, I don't think wind turbines are cost effective/useful for utility/grid power as a national policy.

Wind farms would, most likely, go away if the government subsidies were stopped.

-Bill

Thom

ha ha have fun with your [not needed. -Bill]

I was reading an article the other day where writer was trying to prove that cat kills more birds than human hunting but its not about the ratio my friend ...

vtmaps

froggersix wrote: »

they don't spin fast enough to chop up sparrows.

Large commercial turbines on ridgelines do kill hawks. Hawks like ridgelines and they don't look up while flying and they don't see the turbine blades coming down on them.

--vtMaps

Cariboocoot

burraak wrote: »

So lets discuss something about hundereds and thousends of birds crushing wind mills......

This is a lie.
There may be an occasional bird smacking into a turbine but there are not piles of dead bird bodies under them, nor are they chopped up into bite-sized pieces. As froggersix said, it doesn't happen. More birds are killed by cars and flying into other man-made objects.
And as Bill said the affect of placing any such protection around a turbine would be far more detrimental to power production than helpful to wildlife.

If you can't talk sense about a subject, don't talk at all.