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unclesyd (Materials) (OP)
2 Apr 08 22:44
Last week I while caught by a train I saw 6 nacelles and 6 rotor hubs going by. Today I was caught by the train again and counted 12 nacelles, no hubs going by. This equipment is made by GE at their local facility. It looks like there is an increase in demand for wind turbines as I've never seen more than one unit before.

It is kinda ironic that these components are made by GE in a building built for Westinghouse Nuclear Components Division.
Helpful Member!  patdaly (Mechanical)
4 Apr 08 11:44
Yep, right now they are putting up 350-400 in mid-Illinois. They just finished the same further downstate.

Bring em on!
dpc (Electrical)
5 Apr 08 21:52
So how many of these do you think will still be operating in 10 years?  
metengr (Materials)
6 Apr 08 16:17
Not many if they don't correct gear box manufacturing problems and blade cracking problems. Thus far, gear box reliability seems to be the long term problem in the US. Structural cracks in blades have surfaced with some wtg OEM's. This has been my part time job for the last 18 months.
dpc (Electrical)
6 Apr 08 16:36
They will need another tax incentive program to do maintenance on them probably...
patdaly (Mechanical)
7 Apr 08 11:03
Let me guess, they are not built to the same standards as the rest of the worlds units?

Lovely, I guess I had better beef up my homeowners insurance.
dpc (Electrical)
7 Apr 08 12:06
I'm not sure there are many standards at this point.  

One already fell down in the Northwest during testing.

Helpful Member!  davidbeach (Electrical)
7 Apr 08 12:28
dpc, the one that fell down was being (inadvertently) operated way outside any reasonable conditions.  During the work the blades had been allowed to become fully pitched, should have been fully feathered, the brakes were disengaged, and the turbine was not connected to the grid; there was nothing to limit rotational speed and bad things happen under those conditions.
dpc (Electrical)
7 Apr 08 12:44
David, you're right, they were doing something they should not have been doing, but the guy is still dead.  A more mature control system might/should have prevented this from occurring.  

A rigid boiler code was developed over many years to reduce the hundreds of boiler explosions and thousands of deaths each year.  I suspect this will happen with wind turbines, assuming they stay operational long enough.  

BJC (Electrical)
7 Apr 08 13:04
The guy who was killed voilated standing proceedures, he returned to the nacelle for just a minute to get his cell phone he left in their. He didn't follow any of the lock-out proceedures.
Design on wind turbines to lessen the cost of maintenance seems to be  in order.  The first thing they usually need is a crane or two that can cost $4-1000 a day, plus travel time, set up time. The cranes that can do the job may not be free when needed.  If you could put the generator on the ground it would seem possible to build a hoist into the tower that would handle the blade(S).
dpc (Electrical)
7 Apr 08 14:20
I still feel that violating test procedures should not cause a major structural failure of the system.  Either the structure needs to be stronger or the safety systems need to be truly fail-safe.  

metengr (Materials)
7 Apr 08 14:29
The wind turbine business unfortunately has taken off so quickly in the last 2 years that the problem I have seen has more to do with supplier bottlenecks and qualification with parts as I mentioned in an earlier post versus design. All wtg designs are reviewed and approved by a 3rd party company like G-L in Germany.

The current top tier wtg OEM's (like GE, Mitsubishi, et al) have worked through their blade and gear box reliability issues early on. The current problem is that wind turbines are the flavor of the month for most energy producers.

This means that demand far exceeds the supply, the various wind turbine OEM's know that they have their customers over a barrel. This is where the sub par suppliers begin to supply parts that are not manufactured to the highest quality standards.
jmw (Industrial)
7 Apr 08 15:03
The offshore turbines are bigger still and need special support vessels.


BigInch (Petroleum)
21 Apr 08 13:45
I think this is a case of size outgrowing technology where bigger is not necessarily better.

"What gets us into trouble is not what we don't know, its what we know for sure" - Mark Twain

UBbaja (Mechanical)
2 May 08 14:05
for anyone else stumbling upon this thread unfamiliar with wind power-

pretty comprehensive
unclesyd (Materials) (OP)
2 May 08 15:57
Here are some photos of wind turbine components going to an Indiana wind field. These parts are different from the one's in my original post. These were made in the UK and the ones I saw were made in Pensacola, FL.
metengr (Materials)
2 May 08 18:33
The ones in Pensacola, FL were made by GE Wind. They have a fabrication shop in Pensacola, which I am scheduled to visit. By the way, stay away from any Suzlon S88 wind turbines until the blade cracking issue is rectified.
ewh (Aerospace)
5 May 08 18:08
I don't know where they are made, and imagine they are going to west TX, but I often see them moving west on I-10 (San Antonio area) during my work commute.

Believe it if you need it or leave it if you dare. - Robert Hunter

eyec (Industrial)
5 May 08 20:49
yesterday i was driving along the PA Turnpike near Somerset(US)and came across a smal (maybe a dozen) wind turnines in a field.  my camera was in my bag behind my seat but tomorrow on my return trip i am going to stop and take a picture of one specifically. . .

it had one blade just dangling at a strange angle from its normal position and was not running while the others were truning away.  i will post a link to the picture when i get home.

p.s.  i must mention that i am more partial to MATS (multi axis turbine systems)wind turbines.  the ones commercially available as well as the ones some universities are working with.
unclesyd (Materials) (OP)
17 May 08 7:43
You are probably correct. Aside from what is now under construction it been announced that T. Boone Pickens, famed for oil deals, is behind a 792 unit wind farm in west Texas. The turbines are to be supplied by GE.  
evelrod (Automotive)
19 May 08 13:59
What about the wind farm off the I-10 in the Palm Springs area?  It's been 'operational' for nearly 20 years.  I don't think I have ever seen more than half of them operating at one time and often less than that.  How about the Dagett Solar Project in Barstow?  It's been finished (operational???) since the late 70's and I only saw it in operation once in the early 80's!  I see a lot of flashy videos and 'news' programs...I don't see much real change in power production. Call me a skeptic...I don't see these wind farms any where near a populated suburb (NIMBY?) being accepted...ugly scar on the landscape and too noisy.

patdaly (Mechanical)
20 May 08 9:23
Rod, perhaps not in Cali, but we have them up close and personal here in Illinois.

I do not know where they get the noisy rap, unless from older blade designs, while at my sisters house, with a turbine less than 1/4 mile away, even a bird chirping sounds like a cannon shot compared to the turbine.

Could be they did both of those projects out by you for the typical Cali. feel good purpose, but out here at least, those puppies are turning whenever the wind blows, which is almost always.
IRstuff (Aerospace)
20 May 08 10:11
Possibly.  The turbines in Altamont Pass, where the 580 heads towards SF, have only been partially operational the last decade or so.


FAQ731-376: Forum Policies

evelrod (Automotive)
20 May 08 13:56
Pat, the 500 or so turbines off I-10 near Palm springs make a good deal of noise...perhaps not much individually, but in this high density? (Well, assuming they are even operational). Anyway, the NIMBY thing was just an off the cuff, personal observation.  My other gripe is the Dagett power station. I was working there for a few weeks in 1977 and it was operational.  A few years later it was down and as far as I know it's still down. All I can find is some song and dance about "dust accumulation on the mirrors". Even when we were having 'rolling blackouts' a couple years back, the solar and wind farms were only minimally operational from my observation.  Maybe I'm missing something.  I know from several of my friends that worked on the turbines that they are maintenance intensive...

davefitz (Mechanical)
27 May 08 9:31
Another issue will become paramount once the wind turbine capacity exceeds 7% of system capacity- unpredicted load shedding by the wind turinbes inplies the remaining fossil fired unit be suitasble for a step increase in load, to avoid drastic upsets in system power deliver. I understand this took out the Texas system last year.

In Germany , this is being addressed by retrofitting coal fired units with header type feedwater heaters, and an immediate 10% step increase in steam turbine output achieved by isolating steam exraction to the feedwater heaters.
dpc (Electrical)
27 May 08 11:24
In Europe, the sporadic nature of wind turbine output is stabilized by the massive French nuclear plant spinning reserve.   
ozmosis (Electrical)
16 Jun 08 3:47
chief (Marine/Ocean)
22 Jun 08 19:16

 In the Orkneys they have overcome the inherent problem of wind turbines. That is when there is no wind there is no power delivery.
The turbines supply the power to a Hydrogen generator. The hydrogen is stored  and used to supply a generator engine. The units are small at present, but have proved reliable and they even have a prototype Hydrogen powered car to run around the island.

Offshore Engineering&Design

SomptingGuy (Automotive)
25 Jun 08 12:11
Is anyone around here well versed in the physics behind turbines: the aerodynamics and fluid/structure interaction?

- Steve

KENAT (Mechanical)
25 Jun 08 12:32
I did a report on them in A level Physics Sompting, or is that not the kind of level you meant Somptingwinky smile.

KENAT, probably the least qualified checker you'll ever meet...

j2bprometheus (Mechanical)
5 Jul 08 9:14
      But making the hydrogen is only about 35 % efficient.

      Then using the hydrogen in an engine is probably about 35 % efficient.

       So from the electicity that was generated,  the hydrogen storage system would only put out about 12 % of the original energy ( 35 % * 35 %)

       that's pretty poor overall efficiency especially considering the extra expense added from the hydrogen generating equipment and the engine gen set.


chief (Marine/Ocean)
6 Jul 08 8:23

                I agree it is not a very efficient system, but apart from the initial capital costs of equipment and construction, the payback at 12% will take some time.
 The Orkneys are a remote island area and they are looking at some self sufficiency for their power supplies. The high costs of shipping in fuel are other factors to be considered.
 The present system is a small scale MOM&POP proto-type and obviously lessons will be learnt and it is a small step in advancing uses of clean alternative energy  

Offshore Engineering&Design

evelrod (Automotive)
8 Jul 08 12:35
Interesting interview this morning with T. Boone Picket.  His claim is that existing wind farms, using thirty year old technology are so lacking in efficiency that they need replacing with modern, highly efficient units.
Hmmmm?  In his reference to the Palm Springs wind farm, he may be correct as I never see more than half operating at one time.... New wind farms can replace all existing power generation plants, save coal power, in ten years and stop the power 'drain' freeing up oil and gas for other uses.

His claim is that the U.S. can be well into solving it's energy problems in as few as ten years!  Again, hmmmmmm, I'm just wondering how long to amortize the cost, and what cost are we talking about here?  Hundreds of millions of dollars in gov't. subsidies would be required, that's a given. What political party is going to see to the spending measure that would facilitate such an undertaking?  Our Congress is joined at the hip to the oil industry!  What politician  does not take money from oil industry lobbyists?
Then, again, I'm not the billionaire with gazillion$ invested in wind power. He is building a 4000 megawatt wind farm in Pampa, Texas....That may work there...I've was in Pampa back in '64, but I would be surprised if it had changed all that much. There will be no lack of wind at the "Top of Texas"!

I'm just wondering, how will the rest of the country accept wind farms reaching to the horizon?

jmw (Industrial)
8 Jul 08 12:47
A recent report for the UK suggests that the UKs planned wind farms will need something like 94% backup - this is a measure of the shortfall of power generation in the height of winter on days when the wind doesn't blow.
I think Eon also had some some truths to reveal but I'll need to find the original articles/source for both comments before I can establish what level of credibility to assign them.


dpc (Electrical)
8 Jul 08 12:55
btrueblood (Mechanical)
8 Jul 08 13:52
Our family road trip took us thru the Columbia gorge area last week.  Of the hundreds of WT's we saw, perhaps 1/20 was not operating (these are probably ~20 years newer than the WT's in California).  At the Dalles dam, the spill flow (for helping salmon smolts to migrate downstream) was roughly half of the available spillway (there was a lot of snow in the hills this year, and it is still melting off) --a spectacular sight, probably close to what the original Celilo Falls behind the dam looked like.  There did not appear to be even 10% of that flow coming out of the turbine outlet pool.
cranky108 (Electrical)
8 Jul 08 20:06
The companys I know of backup wind with gas units. What do other companys use to backup wind?
Hydro's nice if you have it available, but most utilities don't have 20% hydro.
dpc (Electrical)
9 Jul 08 11:25
The problem with backing up wind turbines is that the resource must be on-line operating with some reserve capacity to be of much use.  As wind turbines become a large slice of the generation, grid stability and frequency regulation will become bigger issues.   
unclesyd (Materials) (OP)
11 Jul 08 18:22
Hope this doesn't set your time table back. The TV news said that the total thief was about 60,000 lbs of Cu.

jmw (Industrial)
21 Dec 08 11:21
Some cracks in the veneer... admissions that wind power isn't all its cracked up to be:

That the industry has had to modify its declared environmental benefits downwards is because:


A wind farm industry source admitted: "It's not ideal for us. It's the result of pressure by the anti-wind farm lobby."
referring to the admission that wind energy 'displaces' not the 860 grams of carbon dioxide emission for every kilowatt hour of electricity generated as originally claimed but only 430 grams.
Worryingly, one response suggests that we now need twice as many wind turbines....

Rr, no thank you.
This was a dodgy deal to begin with and what this really means, or should mean, is this ain't the solution and the cost benefits do not justify this solution.

However, politicians being what they are and no economic collapse will stand in their way, we are going to tighten our belts and go for it... you wait and see. Maybe the huge investment in wind turbines will be seen as a some sort of modern "New Deal", perhaps a return of the Civilian Conservation Corps? not the TVA or Hoover Dam but wind farms and whatever else the new scientific advisor to Obama comes up with (see for the shape of things to come).



evelrod (Automotive)
21 Dec 08 13:20
I am just SO shocked!!!  

Live around one of these "wind farms" or travel by one and tell me "this is the future"!  The whole idea smacks of overt commercialism to me.  I am not an advocate, as you may have surmised.  "Trust in govt", and trust that T. Boone has OUR best interests at heart is much akin to 'I will respect you in the morning, I promise'...

JLSeagull (Electrical)
22 Dec 08 8:10
I guess that I am a believer.  When I travel in far west Texas I see lots of wind generators along the ridges.  Clearly someone sees these as a commercial venture.  I often see the blades headed west on Interstate 10 driving from San Antonio to Houston; mostly Vestas.  One of the failures on YouTube was a Vestas with a brake failure.

With the next new deal I might bet a bit of money on direct burial high voltage transmission cable in addition to a wind or solar farm.
eyec (Industrial)
22 Dec 08 8:26
T Boone Pickens has put his wind farm on hold because of the drop in oil prices.

says they are not competetive at these low prices!


Steven C
Senior Member

dpc (Electrical)
22 Dec 08 11:58


Clearly someone sees these as a commercial venture

But only because of the energy tax credits - if it wasn't for the tax credits available, I think there would far fewer wind farms being installed.  

cranky108 (Electrical)
22 Dec 08 15:40
Has anyone calculated the other costs of wind generation? Like the cost of following the wind, or the fact that coal, which is cheep, can't be used to follow the wind. We have to use more natural gas, higher cost, to follow the wind.
And how about the cost of added transmission to connect the wind to the grid?

dpc (Electrical)
22 Dec 08 16:11


Like the cost of following the wind

Not sure what you mean by this....  
JLSeagull (Electrical)
22 Dec 08 16:44
The externalities associated with wind are minimal compared to every aspect of coal derived electrical power.  At least natural gas burns cleanly.  Wind is renewable.  The supply of natural gas is diminishing - and cost is increasing.  A few major problem exist with wind.  The more reliable sources for wind and solar are that they are not near most population centers.  This requires transportation and distribution costs.  Where wind is near a population center the people want the pretty view without obstruction by the tall wind generating towers.

Coal is not renewable.  You trash lots of real estate to remove and process coal.  Transportation is by rail although the power could be generated far from the cities too.
stevenal (Electrical)
22 Dec 08 17:16

I think he means the cost the load following source that is needed when the wind dies down.  
cranky108 (Electrical)
22 Dec 08 17:38
I have seen what happens win a 100MW wind farm goes from 100MW to zero in a five minuite time peroid. Consitering that the following unit was a gas fired steam unit, it just could not ramp that fast.
It would be worse with a coal fired unit, which is what you would want to do if you were looking out for your customers pocket books.
A gas turban would be faster, but with the price of gas, until recently, it would have increased the cost to the customers.

Properly wind power, and all it's costs, should be sold to customers willing to pay more for electricity.

So consiter the ramp rates, and what units must be running to accomidate 15%, 20%, or even 30%, MW production on your system. It gets worse if the expected wind production is in KWH, rather than MW capacity.

Not that I'm aginst wind power, but I am aginst mandated higher electricity costs.
evelrod (Automotive)
22 Dec 08 17:44
Bottom line?

They are huge.
They are ugly.
They obliterate the 'view'.
They are noisy.
They are not efficient when the wind dies.
They raise havoc when the wind VARIES.
AND, most of all...NIMBY! (Nimbies elect the legislature)

Anyway, the nimbies and OPEC will kill it in the long run.

JLSeagull (Electrical)
23 Dec 08 8:13
The really big wind generaters are huge.  I don't find them to be any more ugly than cell phone towers.  A wind generator could only obliterate the view of you are standing next to it.  However, they would detract from a pristine view, just like power transmission lines or cell phone towers.

I don't hear wind generators when driving in my car.  When out in the oil-patch I hear the pumping jacks.  They too are noisy when no background noise exists.

Gas turnine generators are not energy efficient whether or not the wind dies.  Gas turbines can produce the peak generation capacity as the wind varies.  Widely spaced wind power farms can compensate from local variation.  However, a high pressure system becalms large areas.

I would love to have about 20 wind generators in my back yard.  I would also love a back yard large enough to support about 20 wind generators.
BigInch (Petroleum)
23 Dec 08 10:54
JL.  If you had a back yard with 1 of them, I bet you'd be desparate to move the house after about a week.  Next time you drive past ONE of them that's spinning, stop the car and roll down the window.  It also seems to be a case of a dBa meter not telling the whole story either, as the actual sound levels are not often above the background noise.  That may be due to the background wind noise blowing on the mic or something, don't know why, but I can tell you personally that I know that they make noise, a lot of it, and it is not an agreeable noise either.  I really can't believe there is any controversy about that.  I would definately NOT want one of these things anywhere near MY property.  All I can say is that I'm greatful for folks like yourself that don't seem to mind them, so please buy as much property as you can and build, build, build.

"Pumping systems account for nearly 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic  (Note: Make that 99.99% for pipeline companies)

JLSeagull (Electrical)
23 Dec 08 12:17
If BigInch thinks that wind generators have an unpleasant noise level then I need to stop off the highway next opportunity and listen.  I might even drive up to the gate for a check.
cranky108 (Electrical)
23 Dec 08 13:56
Has anyone noticed that most of the wind power is where people don't want to live. Maybe it is because of wind.
At some of these locations, with out the wind tower, the cost is very low. So you could have a back yard that big (good luck on finding a job).
But some western states are offering incentives for hireing people in remote locations, which makes wind farms more proffitable.
davidbeach (Electrical)
24 Dec 08 0:24
Farmers in eastern Oregon and Washington love the wind turbines; the royalties from a single tower produce more income than the surrounding farm land.  Not that hard to find farmers willing to sign up to host wind farms.
evelrod (Automotive)
24 Dec 08 13:40
Ahhhhhh!!!  Finally, the REAL reason.

cranky108 (Electrical)
24 Dec 08 21:29
If by real reason you mean money, well you should have known.

The problem is these things are being forced onto utilities with no consiteration on the effects on the customers.

They have there place, don't get me wrong. But when they negatively effect the cost to the customers, it's a problem.

At least with solar the generation curve somewhat follows the load curve.
BigInch (Petroleum)
25 Dec 08 0:54
JL, I was driving by one of our local wind turbine farms today, but didn't have the camera handy.  Next week I'll be sure I have it.  I'll grab some video and sound bytes and post it on You Tube for you.  There are so many of them right on the highway down to Tariffa they make you dizzy just driving by all of them.  Really bad if they are between you and the setting sun.  Damn near gives me epileptic fits.

My brother is doing some work for a company that wants to buy up all wind farm leases they can from WY to SD/MN and sell the huge package off to a big wind utility.  If you still think you want wind turbines, get there before he does.  Fortunately that's NIMBY!

"Pumping systems account for nearly 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic  (Note: Make that 99.99% for pipeline companies)

JLSeagull (Electrical)
29 Dec 08 17:07
I have been watching the PBS episodes of "Spain - On the Road Again" with Mario Batali, Gwyneth Platrow, Mark Bittman adnd Claudia Bassols.  I have seen quaint old Spanish wind mills on the program but not the big modern units.  I suppose that the camera crews don't like them too.
winky smile

I rarely take I-10 very far west of San Antonio.  However, many ridges are covered with wind generators in West Texas.  The Texas Comptrollers office published a wind engergy report showing Texas with a 4296 MW capacity at the end of 2007 out of 16,596 MW for the 50 states.  California was next with 2439 MW followed by MN, WA and IA all over 1100 MW.  As suspected, the Texas Panhandle has the largest wind potential.  This suggests that the western plains are big potential wind growth areas - and not among the largest power useage areas.
BigInch (Petroleum)
30 Dec 08 4:31
The new scourge of Don Quijote!!!

Its getting really UGLY near Tariffa.
I'll shoot some video & sound bytes for you tomorrow.

The installations in the lower right are actually in the Canary Islands, not Morocco.

The biggest problem in developing US wind and solar power gen is the investment in transmission lines required to get the production to markets.  Seems like I've heard a figure of 800 Billion.  ..small change for you guys these days.

"Pumping systems account for nearly 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic  (Note: Make that 99.99% for pipeline companies)

JLSeagull (Electrical)
30 Dec 08 8:15
Significant power transmission issues exist state side.  Most of the US is on a grid with capacity issues during peak loads.  Expect some of that "shovel ready" infrastructure moola headed toward power transmission.  The Texas grid is independent of the other power grids with DC links that could prevent the spiral down during a northeastern brownout.

Although congress threw away 700 gigabuck toward the banks and is making plural gigabuck bad loans to the failing auto industry, most Norte Americanos consider hundreds of billions to be incomprehensible.
BigInch (Petroleum)
2 Jan 09 18:08
OK, got over to the wind farm in Casares, Malaga, Spain  (N 36.409867° E 5.282712°) where there are 35 large (1 MW ? ea)wind turbines installed on a ridge before arriving at the town of Casares.  These don't do much for the view IMO, either, but its better than smokestacks I suppose.  I just know that before these sprouted, it was much prettier.

A short video is posted at,

I think the noise can be best described as "wind turbine snoring."   There is a steady humm from the generator, a swish from the blades and seems to be an extra wheeze when a blade passes the column.  I was able to get into the farm, as the gate was open and took the video right next to the column of the first one I reached.  The wind was relatively light, probably 10 mph while I was taking the recordings.  I was there on a day when the wind was 25-30 mph once before and the noise was considerably louder.  Easily audiable from several hundreds of meters away and I believe it was much louder at that distance than the recording I took yesterday.   I didn't notice the generator humm from a far distance, but standing below one it is audiable.

In any case, last time I had a hotel with thin walls, the guy next door kept me up all night and he wasn't this loud.  Maybe I'm just too sensitive, as I'm pretty used to the usual peace and quite we have around here most of the time.  Well, except for the cracks of the golfers teeing off from #2 and ... it is true that the summertime frogs get pretty roudy when they're partying hard down at the water trap all night.  Have to check and see what's in that water.

"Pumping accounts for 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic  (Note: Make that 99.99% for pipeline companies)

davefitz (Mechanical)
5 Jan 09 8:02
A good powerpoint file on the ERCOT  wind turbine system upset of 24 Feb 07 is on the attached link. Loss of 1.5 GW in a 90 minute period due to uniform tripping at a 55 mph windpseed initiated the rapid, unpredicted  loss of generation, and uncontrolled re-loading of the turbines led to later system disturbances.

BigInch (Petroleum)
5 Jan 09 9:34
Hence the need for the 800 B above to create a robust grid.  No doubt there will be some enterprizing company that will sprout up with 1024 huge mobile flywheels for lease.    

Do they make noise?

"Pumping accounts for 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic  (Note: Make that 99.99% for pipeline companies)

patdaly (Mechanical)
5 Jan 09 11:13
BigInch, those are the same Turbines we have here in Central Illinois.

You are right, they are just way too loud, you can barely hear yourself think.

Then a Cricket chirps and you about jump out of your shoes.

There may well be a problem with the grid bouncing, but to say they have a noise issue is a bit overboard.

Typically my house whistles louder in the wind than those turbines.
BigInch (Petroleum)
6 Jan 09 2:14
Like I say, maybe I just don't like the noise however many dBa it may or may not actually be registering and remember ... the wind was minimal when I made the recording.  Actually I think the worst thing about them can be the shadow flicker effect.   

"Pumping accounts for 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic  (Note: Make that 99.99% for pipeline companies)

BrunoPuntzJones (Materials)
6 Jan 09 12:30

All other issue involving wind aside, don't you think "I don't like that they cause the light to flicker on my drive home" is a pretty poor reason to oppose a technology?
BigInch (Petroleum)
6 Jan 09 13:08
Wrong.  I don't oppose it.  As most of us are aware of the advantages, I'm simply discussing some of the disadvantages of the technology.  I will also admit that most of those negative aspects can be controlled for the most part with adequate setbacks that, if respected by utility companies, should make them relatively benign additions to the landscape for the most part. I agree they are better than nuclear power plants, belching smokestacks, biofuels made from edible plants, diesel power drilling rigs, heck, just about most anything, but nothing says I have to like everything about them, right?  

"Pumping accounts for 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic  (Note: Make that 99.99% for pipeline companies)

cranky108 (Electrical)
6 Jan 09 15:01
The flash factor is why some companys don't place there towers near peoples homes, or so I am told.

My bigest peves with wind power is it usually arrives when we don't need it, mainly at night. And you can't shedule it, so you have to follow it with a fossel unit, which adds wear and tear on the fossel unit to try to ramp up and down that much.

Now if you can store the wind power some how, and release it as it is needed, I don't have a problem.
jmw (Industrial)
20 Jan 09 7:21
Another and apparently unexpected problem with turbines - icing:
(NIMIBY's please note: this wind turbine in Norfolk is owned by a Cornish power generating company....)
Note also the comments on light flashing and noise.
I would suggest that even the most dedicated supporters of wind trubines would be concerned about the location of this one.


BigInch (Petroleum)
20 Jan 09 8:38
Strange that it would be ... unexpected, being outside in the cold, wind, rain, etc.

"Pumping accounts for 20% of the world's energy used by electric motors and 25% to 50% of the total electrical energy usage in certain industrial facilities." - DOE statistic  (Note: Make that 99.99% for pipeline companies)

BigInch (Petroleum)
29 Jan 09 16:48
Found a vendor noise curve. Attch.  Its not my imagination.  This one begins at 100 dB


"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

jmw (Industrial)
30 Jan 09 4:58
Great, that means that just as townies can move to the country and get church bells silenced and farmers hauled off to jail because their animals make too much noise and/or smell and they spread smelly stuff on fields that will be used to grow crops, we can hope to have wind turbines either turned off altogether or have restrictions imposed on when they can be used.

PS, in the chart, why not wind speed at the hub height, why 10m?


BigInch (Petroleum)
30 Jan 09 6:44
Lowest velocity in the blade disk diameter?

There are restrictions on where they can be used in most places already, but there are a few articles I've seen where the local residents say the restrictions have been ignored, or the area simply rezoned, by local town councils over some objections.  If the existing restrictions were followed, it would have been doubtful that anybody would have complained about noise.

"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

jmw (Industrial)
30 Jan 09 6:56
It seems to me that there ought to be some standard procedure for determining the effective noise generated based on a variety of factors and derived from a study which should surely include some consideration of tower height, diameter and ground effects.

The wind turbine is not, close to, a point source but with sound generated across the swept region.
Measuring the sound at the hub is as reasonable as any other approach. We are not, one presumes, to believe that there is no noise at the hub, just that at the hub the noise generation may be less, as you say, due to the local velocity, but it may well be that along the hub axis is the most intense noise as all noise generating points of the swept plane are equidistant from that axis.

Making a local measurement close to the swept plane but radially displaced is not the most effective or representative method.  


BigInch (Petroleum)
30 Jan 09 12:33
I think the highest reading would be in the region of the blade tip (it is the highest velocity of anywhwere on the blade).  Also as it passes the tower column, there seems to be an increased whooshing sound when the blade becomes vertically aligned with the column.  Perhaps the velocity of air spilling off the blade and then passing around the tower is slightly increased.

"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

cranky108 (Electrical)
30 Jan 09 14:57
Measuring noise at the blade tip may be problematic. Would it be more reasonable to measure at some distance where people might actually be. Say 100 foot from the base of a tower, at a heigth of say 6 feet.
BigInch (Petroleum)
30 Jan 09 16:04
I think they were probably trying to establish the maximum sound level, rather than what a person could typically hear standing under it; te idea being to be able to predict sound levels in any direction from the point of maximum energy.  It would surely be easier to work with the accoustic radiation if you know the maximum value at a point, rather than take the measurement at 6ft, reverse it to 10 m altitude to obtain the max energy level, and then go out from that point in any direction.  Hey, but I'm just guessing.

"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

GregLocock (Automotive)
31 Jan 09 2:29
Note that that graph is a sound power level (SWL), not a sound pressure level. So you need to do some maths to determine what someone would hear at a given distance, and you don't have the directivity graph so you can't really do that. A person talking loudly has a SWL of around 90 dBA.


Greg Locock

SIG:Please see FAQ731-376: Forum Policies for tips on how to make the best use of Eng-Tips.

jmw (Industrial)
10 Feb 09 8:40
Here's a sad sight:
However, we are assured this £1million wind turbine did not fold up because of UFOs but because of the far less interesting (to the public) mechanical failure.
STill, "Wind Turbine Struck by UFOs" made for interesting reading.


jmw (Industrial)
29 Mar 09 16:55
I had a call from Sustainable Scotland this week touting the next conference and claiming of wind farms that the evironmental issues were all positive as even the RSPB "were calling for them".  There followed an unsatisfactory dialogue about raptors and bats... and a suspicion that the RSPB position was being misrepresented a bit.
Are the greens all now in favour? Perhaps not as this article suggests:
Note who the author is and check out his green credentials....


BigInch (Petroleum)
30 Mar 09 12:48
I read it as the Greens are willing to cooperate, if the batbeaters are willing to leave the reserve areas alone, as well they probably should anyway.  That dosn't sound like total capitulation.  More like a plea for reason and some form of coexistance.

"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

jmw (Industrial)
12 Jun 09 7:40
An interesting article in the Guardian (
It says that climate change (contrary to the understanding fostered/promoted by Al Gore in his comments on tornadoes etc.) is responsible for significant drop in winds.

Of course, the article hasn't been published yet, it has been, as is commonly the case these days, "leaked" to the press prior to publication in the "peer reviewed Journal of Geophysical Research" which one supposes is meant to imply that it is peer reviewed when it actually makes no such claims; indeed, the article may yet fail to be published.

In any event, they seem to be laying the groundwork for the excuses that will be trotted out when everyone discovers that wind farms don't generate nearly as much energy as promised.... its all due to AGW of course.


unclesyd (Materials) (OP)
13 Jun 09 13:24
I saw the same information presented as fact on TV news. One thing that was notable about this segment was that the co-anchor asked a DB question, "What happens when there is no wind?". The answer was you get electricity off the grid.

The local GE Wind Turbine Plant is calling back workers and shipping components 2 x 2 x 2....
cranky108 (Electrical)
15 Jun 09 0:36
you get electricity off the grid??

So who puts it on the grid??

Can I become a journlest and ask DB questions??

Does anyone care if the power on the grid goes off??

That's the reason science classes are required in college.
Can you tell how miffed these people make me??
JLSeagull (Electrical)
15 Jun 09 7:34

Uncle Syd,
DB question?

The grid includes many Mega boiler steam turbine generators (assorted fuels) and gas turbine driven peaking units.  If wind accounted a far greater percentage of the power then it could be a problem.  However, presently the grid can accomodate diverse renewables with some solar, some wind, etc.  The loads are variable too.

One could rationally advocate both nuclear mega generators and renewables; and perhaps oppose new coal burning plants.  Such advocacy is lame without selecting a renewable based electrical utility company.  This sort of ties back to the irony mentioned in the original post, "... components are made by GE in a building built for Westinghouse Nuclear Components Division".  Sure, coal will return when we use up all the uranium, wind and sunshine.  winky smile
jmw (Industrial)
15 Jun 09 8:12
Anthropogenic Global Warming.... maybe we need a glossary for these topics.


unclesyd (Materials) (OP)
15 Jun 09 16:58
The Co-Anchors were a male and female (blond) and the male gave the information in "technical way" and after his spiel the female asked the question "What happens when there is no wind?" to which he gave her the look of why would you ask such a dumb (blond) question. His answer was that when this happens you get electricity off the national electric grid. Her question was related to information presented that there was going to be a fair reduction in available winds based on the 1973 survey.  
jmw (Industrial)
15 Jun 09 19:40
Perhaps she gave him a big kicking afterwards?


cranky108 (Electrical)
16 Jun 09 0:07
In many locations there is a low voltage ride through requirment for power producers including wind.
Why do you think that is?

It seems that someplace doring a fault there was a loss of several hundred megawatts of power production.
What happens when you loose several hundred megawatts on the grid? The frequency can drop, and automatic load shedding goes into effect, or another stability problems comes about.

Solution: require spinning reserve of firm power from all power producers.

Problem #2: because of heat generation sources nucular and coal generation has a limited ramp rate.

Soultion2: use gas turbins to follow the wind.
How ironic that we have to follow the green power with the most expencive energy source.
jmw (Industrial)
16 Jun 09 5:23
Well, it needn't be gas turbines.
I am told by a Dutch friend (I haven't checked)that the Dutch are constructing a new bolder (dyke) so that they can use surplus wind energy to fill it and when the wind drops they can use the outflow to drive turbines...  


cranky108 (Electrical)
16 Jun 09 13:02
True pumped hydro can be used to store energy, but currently there are very few operating. And there is a growing resistance to building lakes and dams, as well as the cost to aquire land for these.

Battery energy storage is also progressing, but again there are few of these, and the capacity is somewhat small.

There is interest in compressed air storage, but this is actually a suplement to a gas turban plant.

Yes I've heard of H2 storage, but there are none that I know of operating.
cranky108 (Electrical)
16 Jun 09 13:11
I think the one thing many people don't understand is the grid is a balanced system. The consumption must be balanced with generation. The two must match or bad things happen.

I know there is some inertia in the grid that allows some percentage of temperary unbalance. But this inertia isen't as great as some people seem to think it is. It is not several hundred mega watts like many wind developers would like us to believe.

That is the reason we call wind non-dispatchable, or non-firm power. It requires a normal or storage source to inversly follow the wind.

Most utilitys seem to top out at inversly following the wind at about 10 to 15% of total generation.
jmw (Industrial)
16 Jun 09 14:24
Not sure about battery storage.
Isn't that pretty damned expensive and just how quickly can you ramp up demand on a battery?

Pumped Storage schemes would seem to offer some pretty good ramp up response to power demand I would have thought (but i guess it depends on the available head... I can see the Dutch Polders will have to be built with enough head to generate a goodly amount of electricity even at high tide... of course, they will be reclaimig land from the sea as usual.

By the way, I don't see there being a problem with cost.
If there were, we wouldn't be investing tax payers money in wind farms, would we now?
So it stands to reason that whatever is necessary to make wnd farms work will be "necessary" and hence afforded.
The most interesting is probably Cruachan Power Station (


JLSeagull (Electrical)
16 Jun 09 16:52
As I understand my grid, frequency is part if the balance.  Dispatchers monitor Real Time via GPS type data against clocks running on the grid.  As the load increases the frequency is pulled down until the generation capacity catches up.  The frequency swing is small.  Interfaces between major grids are direct current to prevent one grid from pulling the frequency down on another grid during a brown-out.

As my understanding is very basic, perhaps cranky108 or others can add some sophistication to the technical issues.
cranky108 (Electrical)
16 Jun 09 23:03
The ties between grids is DC but not to protect the grids. The three major grids are so large that a small difference in frequency between any two whould cause several thousand Mega Watts to flow between them. The problem with tieing the grids is no single line can carry that much power flow.
The DC allows the control of the flows between the grids.

Actually for a devation of frequency several major generation plants will be adjusted to make up for that difference. Sounds eazy, but currently there can be some large penilitys for inadverent flows.
Most companies are required to balance the in and out flows to keep the grid balanced. The companies that are not required to balance there flows are under the umbrellia of a balancing athorty which keeps the balance.

For major frequency devations customers may be shed to keep the remaing grid balanced. This is followed by a NERC investigation for the cause, and possible penilitys.
unclesyd (Materials) (OP)
17 Jun 09 14:32

Do they still have lights bulbs on each circuit to look at the frequency differences?
alehman (Electrical)
17 Jun 09 22:03
There seems to be some interest in sodium sulfur batteries with wind energy. I talked to an NGK rep a few weeks ago. The price is still quite high - as much or more than the wind turbines themselves.

GE announced a new $100M NaS battery plant in New York, so they must believe there is a market.

"It's always fun to do the impossible." - Walt Disney

cranky108 (Electrical)
17 Jun 09 22:58
Not the newest designs. But they are a good idea to be sure, as a wiring error can cause a 180 degree sync of a generator on a single phase syncscope.

Usually they cheepout and only install a single phase PT on one side of the breaker.

At least someone is looking at the wind storage issue. People should have seen this comming.

unclesyd (Materials) (OP)
8 Jul 09 16:15
Here is some information on the Pickens Wind Farm in Pampa, Texas. It looks as if he could get the money, there is nowhere to plug it in.
cranky108 (Electrical)
9 Jul 09 9:36
I saw Pickens had some techicnal problems. Probally could not get the 4000 MW on to the distribution system.

He probally relized that where theres wind, there isen't people, or power lines.
jmw (Industrial)
3 Aug 09 8:28
Wind Turbine Syndrome (WTS)
A report now to be published in book form:
The article linked is typical of many.
However, the report must be considered very vulnerable simply on a statistical basis and some genuine credence given to the critics.
Whether or not there is a real health risk might only be determined by further research -  oh dear, it is often so very costly to debunk some spurious theories, should that be the final outcome.



JLSeagull (Electrical)
3 Aug 09 12:51
Living too close to wind turbines ...
2 km

Nuclear power plants
Steam power plants
Gas Turbine power plants
Sewage treatment facilities
Water treatment facilities
Sea coasts
... preditors
BigInch (Petroleum)
11 Aug 09 11:55

"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

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