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There's a Wind Turbine On the Horizon With Blades the Size of Trump Tower
merbs writes: Imagine a stretch of open ocean, populated by a swath of wind turbines with skyscraper-sized blades, whipping into the gusts like enormous palm trees. The vision is partly terrifying, partly inspiring, and being taken entirely seriously by the federal government and one of our top research laboratories. [Sandia National Labs, in an effort led by the University of Virginia] has unveiled the preliminary design for a new offshore wind turbine with 650-foot turbine blades. That, as its announcement points out, is twice the size of an American football field. It's also roughly the size of Trump Tower in New York.
Is there nothing that doesn't somehow tie back to XKCD?
https://xkcd.com/556/
Seriously, this is cool - but the Trump name drop is as bad as apple-baiting.
Make sure everyone's vote counts: Verified Voting
Mega installation which require mega capital which allow power companies to centralize production, control distribution, and charge consumers.
It is more efficient and less prone to failure to have distributed production with small scale wind turbines, photovoltaic, etc. on peoples' homes. But then, well, where's the profit to the established interests?
I need to know how big it is in terms of Libraries of Congresses. Use standard units! That is approximately 12 LoC. Or 15 in Canadian LoC.
It's also roughly the size of Trump Tower in New York, maybe a more relevant reference point here, since we're talking scale and bluster.
Large turbines spin slower, and hence will not do any chopping. Birds can fly around it, although some won't and it will be on par with a stationary skyscrapers that kill plenty of birds too.
Generally, bigger is better in wind turbines. Power generated is proportional to swept area, more mass means cleaner power which leads to more efficiency, and yes, larger, heavier turbine blades are more survivable in weather events. Modern turbines automatically self-furl as required, in much the same way that modern helicopter blades will auto-gyro in the event of an engine failure, and the mechanisms that do this work better if they are bigger.
All that being said, weather can destroy literally anything less than planet-sized. But if weather brings down a modern windmill, the damage done by the weather event itself is likely to dwarf the damage done by the failure of the turbine and tower - unlike the failure of a large hydro dam, for example. And afterwards you can rebuild it with very few worries about the kind of large-scale, long-lasting contamination that other forms of power production (such as coal or fission) create during a weather event failure.
Really only solar has a comparably benign failure mode in weather events - basically if you get hit by a flying chunk of solar panel or wind turbine blade, that's how you can get hurt, which is why some people prefer such things to be set up well offshore or in deserts.
living life in peace
Can we use sane measuring units please?
How many stacked bananas is that?
On the contrary, this is probably the best way to make windmills bird-safe. The bigger the blades, the slower they'll move.
NASA Wind Turbines approached this scale in the '80's. Unfortunately, this was a previously-unexplored area of aerodynamics for NASA, and they had mechanical stress and noise problems (including subsonics) and were all demolished. I think there was one near Vallejo, CA being taken down when I got to Pixar in '87, and one in Boone, NC, which famously rattled windows and doors.
The art has since improved. I took a ride to the top of the turbine at Grouse Mountain, that was fun! That's the only one I have heard of where you can actually get to see it from the top.
Bruce Perens.
If it is far enough out to sea, there shouldn't be to many birds in the first place.
... if a blade were the size of Trump's ego.
^Obviously didn't read the article
Imagine a stretch of open ocean, populated by a swath of wind turbines with skyscraper-sized blades
Now imagine those wind turbines getting hit by a hurricane.
And now imagine them self-stowing into a "secure" configuration, until the hurricane passes.
If it weren't for deadlines, nothing would be late.
The RPM will be slower, but I very much doubt the tip speed will be substantially slower. I'm pretty sure the design tip speed is fundamentally a certain percentage of the wind speed, independent of the design disk diameter. That's certainly the way propellers work.
It's the tip speed that kills. As a matter of fact, larger blades are probably harder to avoid, because as they rotate they are coming from farther away.
On the contrary, this is probably the best way to make windmills bird-safe. The bigger the blades, the slower they'll move.
They are totally alien structures to a birds perception way out there in nowhere flying at night and may not even recognized as danger until it's too late.
Blades the size of the Trump ego.
FTFY.
"National Security is the chief cause of national insecurity." - Celine's First Law
I'm sure that coming into contact with the tip of a wind turbine would kill or seriously damage you, but there's evidence that some animals aren't actually colliding with the blades. Some post-mortem studies (of bats IIRC) showed evidence of ruptured lungs (but no blunt-force trauma), implying that the animals were killed by entering the zone of low pressure behind the leading edge.
They sentenced me to twenty years of boredom
650' at 1 rpm is 45mph at the tip. More than enough to kill a bird, or because of its size a flock.
0mph is enough to kill a bird considering how many die just from hitting large buildings.
I'm no opponent to wind power, but the blades aren't really the stumbling block with making wind turbines larger and better. We want to build our wind turbines larger as they will rotate slower and capture more energy. The problem is transferring that energy through the hub of the turbine. More energy and slower revolution means huge torque which has to be sped up to generate electricity. Wind turbine gear boxes are still the constraining factor for improvements. Do we have any idea how these designs plan on handling this problem?
If anybody wants to read about an actual attempt to address this, here is a thesis on a system which uses wind turbines to run gravitational pistons to directly generate compressed air.
I'd be surprised if Trump even has a PR team. He basically just says what's on his mind (instead of the usual canned responses politicians typically give) and people either fawn over it or they go ape shit.
Strange as it seems (because you can't go thirty minutes without hearing or reading his name sometimes) his campaign is spending hardly any money, so I'm not sure what kind of a PR team he could even hire with such a paltry sum. Very well disproves the notion that money buys votes. If it did, then Hillary should win by a landslide while Trump should be dead last even among Republicans.
http://www.businessinsider.com...
Yes, larger turbines spin at lower rpm but the tip speed is about the same regardless of size. There are physical limitations.
Actually I didn't some checking and found a paper titled Optimal Tip Speed Ratio [PDF]. The tip speed ratio is the tip speed/wind speed. The paper says:
For grid connected wind turbines with three rotor blades the optimal wind tip speed ratio is reported as 7, with values over the range 6-8.
So the optimal tip speed depends on the wind speed but for practical reasons the tip speed may be limited to non-optimal values.
Large turbines spin slower, and hence will not do any chopping. Birds can fly around it, although some won't and it will be on par with a stationary skyscrapers that kill plenty of birds too.
Someone doesn't understand circular motion. Small turbines with small blades spin quickly. Chop chop chop.
Large turbines with large blades spin slowly. BUT the blades are longer. The further from the centre of rotation you get the faster your velocity. I.e. Chop Chop Chop.
The birds wouldn't even see it coming. The "problem" really doesn't change.
And I use quotes because the problem is nothing compared to the death of birds caused by other human activities.