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Wind Farms Can Interfere With Doppler Radar
T Murphy writes "Wind farms can appear like storms or tornadoes on Doppler radar when placed too close to the radar. Tornado alley is a good area for wind farms, and good terrain for the turbines is also ideal for Doppler radar. With many new farms being constructed, the problem is growing. A false tornado warning was issued in Kansas by a computer, although canceled by a meteorologist aware of the problem — there are fears that false positives will grow. Worse would be a tornado ignored as a wind turbine. While meteorologists are trying to work with wind farm owners to shut off the turbines during bad weather, they have no control over the placement or operation of the turbines. Efforts are being made to improve detection technology to avoid further problems."
The problem is likely that the technology is very simple and as a result -- imprecise.
To "naive" persons like you and I, we may say it's too small or well couldn't you just program in that a vortex seen at this height (100m is quite a bit lower than where most funnel clouds are formed, cumulonimbus clouds are at 2000 ft), but it may be technically very difficult to distinguish in such a way. I've never worked with the data they gather so I can't speak expertly, but I'd imagine if it were a true 3 dimensional scan, you'd be able to easily determine the height and size of an anomaly and discount it or mark it way down on the danger scale, but that could be totally unreasonable.
Any meteorologists around?
If only the wind turbines were on stationary towers, then they might be able to map them, and use such a map to inform their interpretation of the radar data.
Nerd rage is the funniest rage.
Wind speeds above the maximum design speed will tear the mechanical gearing apart - that is if the wind surfaces don't rip off first.
Most wind turbines already automatically lock themselves when wind speeds exceed certain design specifications to protect themselves from damage.
I am not a meteorologist, but don't tornadoes occur because there is a horizontal boundary between two different types of air masses, and the tornado acts as a funnel to equalize the pressure between the two or something? Maybe wind turbines, and the mixed and turbulence they cause actually prevent tornadoes. Who knows? And, don't many tornadoes occur over particularly flat land? The turbines might reshape the landscape enough to disturb the atmosphere enough to prevent them. Turbines looking like tornadoes on radar make me think i'm not totally crazy.
I'm not sure that you realize the limitations of the radar systems themselves.
The nexrad doppler radar system uses systems designed in the early-mid 80's. Three meter resolution? Try 1km during the best situations.
Very small investment considering the cost of the actual wind farm itself.
I'm sure the hardware investment would be relatively small, but the cost to put eyes in front of the screens would probably be much more significant.
On the Oregon Cost born and raised, On the beach is where I spent most of my days
My question is: how do you "shut down" a wind farm? The wind blows, the windmills turn.
It's called a brake.
This is what slashdot is for, making you aware of complicated technology which you couldn't possibly have heard of from other sources ;-)
You can't take the sky from me...
Wind turbines should have a more or less predictable (and hence, recognizable) radar signature. IIRC the US military use turbine signatures (of aircraft engines) as part of non-cooperative target recognition (NCTR), i.e. the ability to recognize the aircraft type from a radar return, without having to rely on IFF transponders. But this probably requires better radars and processing than Nexrad can provide.
yes the blades move in a circle obviously and yes that can be perceived as a tornado. But this 'tornado' would literally never move from the spot the pole is planted on.
Unless the radar is imaging the 'downwind' effects of the turbine, this should be a trivial thing to look at and see clearly for a false positive.
People in cars cause accidents....accidents in cars cause people
So a Fox affiliate employee took the opportunity to...
1) Downplay some senseless and sensationalist bit of fear-mongering...
2) While saying something nice about a green technology that suffers from a lot of NIMBYism...
3) And he based it all on solid science and some common sense?
He was fired immediately after, right?
If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
Buildings cause the same problem; anyone familiar with coherence and/or constructive and destructive interference of electromagnetic waves (or any other type of other wave) would say "No sh*t, Sherlock!"