November 5, 2005

Wind turbines require high maintenance

It's not just the gearbox. You've got 40 tons of rotor blades turning and changing pitch, attached to a 70-ton nacelle which turns on top of a 250-foot-high tower to catch the wind. A mechanical challenge in any environment to be sure.

The following is from John Galambos, "Brooklyn wind turbine performance over 12 years," presented at New Zealand Wind Energy Association Conference, 31 August 2005. Remember that this single turbine near Wellington (N.Z.) is a demonstration installation, with all the money necessary thrown at it to keep it going. Since most of the financial benefits in the U.S. disappear after a few years (6 years for accelerated depreciation, 10 years for production tax credit), the more likely scenario for most facilities is abandonment, as with many of those in Altamont Pass, California, and the sad specimens at South Point, Hawaii.


Years 1 and 2

Gearbox oil issues with build up of black gunge
  • oil type changed
Part of skylight roof section vanished during 1994 storm
  • 38.5 m/s 10-sec average
  • Estimated 45m/s 3-sec gust, turbine rated for 70m/s 3-sec gust
  • Anemometer cup vanished (years 5 and 11 also)
Slip coupling operating too frequently, required replacement
  • High wind shutdown changed from 25 to 22 m/s
Blackening of gearbox oil

Years 3 and 4

Blade inspections revealed gel coat failures
  • Appear to relate to damage from thrown stones
Tower to foundation ring flange-to-flange bolts started failing
  • Managed by monitoring and change out
Numerous minor factory technical upgrades continued
  • Driven by Service Bulletins not issues on site
Yaw drive issues, noisy
  • motors and worm drive gears replaced
Years 5 to 9

Pitch accumulator leaking - replacement with production loss

Controller required Y2k modifications

Yaw drive gearboxes replaced

Ongoing issues relating to EMC
  • Susceptible to strong local FM radio transmission
Gearbox low speed shaft stiffener fitted
  • Factory modification for high winds
  • Internal expansion sleeve to hollow shaft
  • Too late, damage done, gearbox would require replacement before long.
About year 10

Gearbox high speed shaft bearing failed at 9+ years
  • Noisy gearbox operation
  • Before original gearbox was replaced
Weather mast guy hardware failed
  • Repair can have safety implications
Gearbox replaced at 10 years
  • Refurbished unit, "as new", with warranty
  • Shaft end floats outside maintenance tolerances when delivered
  • Bearing replaced after 3 months
  • Gearbox replaced again after 13 months
  • Condition monitoring trials unsuccessful
Years 11 and 12

Nose cone replaced
  • Disintegrating
Tower section joining bolts corroded
  • Replaced at 11 years
Pitch linkage connections failed,
  • Rods damaged and replaced
Yaw ring and yaw gears failed
  • Long outage
  • No local parts
  • Numerous control card replacements/updates to Service bulletins
  • Included fans to control cards, oil filtering etc
  • Communications issues at times – not turbine related
  • Distribution disturbances have tripped the turbine
  • Some misc contactor failures, replacement repairs, consumables etc.

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"Wind Powers American Dream"

Now-freelance journalist Judy Miller is already working again, using her special access abilities to report the real truth, i.e., the truth those in power need us to believe. Fresh from her work to promote the disastrous invasion of Iraq, she now turns to the domestic challenge of pushing unpopular industrial wind facilities onto communities across the country, as this excerpted story from tomorrow's Washington Argus shows.
Wind Powers American Dream

by Judith Miller

Washington, DC -- I have just spent two weeks embedded with the president of the American Wind Energy Association and cannot convey strongly enough the urgent need for massive wind power development in this country.

Randall Switscher took me with him to see site after site that was either totally lacking industrial development or mostly wasted with low-grade agriculture.

"These people desperately need our help," Randy told me. "We need to bring them into the 21st century, get some investment going there."

Randy's model is the transformation of Nigeria by the presence of foreign oil companies who built schools, hospitals, banks, and communication infrastructure. Nigeria now rivals Sweden in measures of equality and health, he says.

During a retreat in the lovely unspoiled mountains of Vermont, I met Keith Dewley, a college-educated architect. He told me how grateful he is to Mr. Switscher for providing a beacon of hope to Vermonters. It is now normal for a Vermont child to hope to go to college, and that is directly a result of the activity of wind developers from outside, he told me.

Keith's interest verges on the artisitic. "What I learned in college was that aesthetics are about social constructs, about what we expect from our lives. Are we defined by hayfields strewn with rotting manure and mountains left to grow wild without any consideration of financial development needs? When I look up, I want to see the future!"

There are, of course, some holdouts who fear the changes Randy represents. Others selfishly want to preserve a system they have benefited from, however backward. Randy admits that the campaign to win their hearts and minds will be long and hard.

"We may not ever convince some of them," he says. "But we're going in there anyway, because that's our duty as world citizens. Sooner or later they'll have to get used to it. Our mission is bigger than any one of us."

Keith Dewley's daughter Hilary, a proud sophomore at the University of Vermont, echoed the enthusiasm of her elders. "The ancient Egyptians built pyramids as monuments to their beliefs. That's what wind turbines are -- just knowing they're there we can feel better going about our business."

Progress wouldn't be possible without a strong government commitment. I am currently embedded with an analyst in Goldman Sachs and will be writing soon about why massive profits are necessary to guarantee the success of wind power development.
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November 3, 2005

Wind power facts

The most frequently unknown aspects of industrial wind power, according to the shared experiences of people trying to educate their neighbors, are the enormous size of the turbines, the new or upgraded roads required, the irrelevance of oil to electricity generation, and the virtually nonexistent effect of wind power on emissions from other sources, such as coal. These have been compiled into a FAQ page at

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High cost, low benefit

Here's a picture of what appears to have been once a lovely open vista in Hungary.

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The gearbox: wind power's Achilles' heel

This month's Windpower Monthly examines a little-known twist in the "mature technology" of large-scale wind turbines:

Gearboxes have been failing in wind turbines since the early 1990s. Barely a turbine make has escaped. Six years ago the problem reached epidemic proportions, culminating in a massive series failure of gearboxes in NEG Micon machines. At the time, the NEG Micon brand was the most sold wind turbine in the world. The disaster brought the company to its knees as it struggled to retrofit well over one thousand machines. It has since been taken over by Vestas, the world's largest wind turbine manufacturer. Vestas is still grappling with the aftermath of the gearbox catastrophe.

The wind power industry and its component suppliers now believe that such major series failure of gearboxes is a thing of the past. Today's far larger and more sophisticated turbines, they say, are safe from mistakes encountered in early phases of technology development.

Bigger turbines, however, are proving to be far from immune to gearbox failure, as Windpower Monthly reports in its November issue. ...

The wind industry's gearbox problem has for years been shrouded in secrecy. While blame for the failures has been spread far and wide, questions outnumber the answers by far. At Windpower Monthly we set ourselves the task of finding out the true scale of the problem. Why is it that gearboxes in wind turbines have so massively failed? What is the solution? ...

The good news is that understanding of the highly complex loads that gearboxes -- and particularly their bearings -- are subject to is being helped by a new industry willingness to co-operate and face up to the challenges of wind power's rapid technological evolution. But only time will tell whether a definitive solution has been found -- and whether it will stay the course as wind turbines get ever bigger and more demanding of engineering ingenuity.

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November 2, 2005


Here's a picture from the October 9 Watertown (N.Y.) Daily Times, of some of the approximately 150 turbines in Phase I of the Maple Ridge Wind Farm on Tug Hill in northern New York. A complete concrete plant was built just to provide for the massive foundations.

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Wind barely better than nuclear

George Monbiot wrote in the October 25 Guardian (U.K.):
Ten cents of investment, [Amory Lovins of the Rocky Mountain Institute] shows, will buy either 1 kilowatt-hour of nuclear electricity; 1.2-1.7 of windpower; 2.2-6.5 of small-scale cogeneration; or up to 10 of energy efficiency. "Its higher cost than competitors, per unit of net CO2 displaced, means that every dollar invested in nuclear expansion will worsen climate change by buying less solution per dollar." And, because nuclear power stations take so long to build, it would be spent later. "Expanding nuclear power would both reduce and retard the desired decrease in CO2 emissions."
It is notable that wind power is almost as bad an investment as nuclear power for reducing CO2 emissions.

Note: I pointed this out, that wind was hardly better than nuclear, to Mr Monbiot, who has written an incisive critique of the "wind power madness" yet still supports it. His reply was, "20-70% hardly better? Try telling that to an economist." One hopes that some economists are better at math than this. The comparison in this analysis is to what ten cents could buy if best spent, namely, 10 KWh of energy efficiency, so that wind is only a 2-7% better investment for reducing CO2 emissions than nuclear.

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