While collecting photos of cranes building windmills, I learned a lot of the crane work is doing maintenance after they have been built. The wind may be free, but the maintenance is not. Replacing a nacelle because of a bad bearing requires more crane work than building the windmill in the first place. And rebuilding them after their design lifetime of 20 years requires a lot of crane work.
I've noticed that a windmill farm along I-57 has not been working during my last two trips down south. I've seen a Dirty Jobs show where they have to climb up in the nacelle to do routine maintenance. Unfortunately, I don't remember how often they have to do that. But it struck me that it was often enough that it was a full time job for some people because by the time you have finished that last windmill in the farm, it is time to start over again with the first windmill.
I found this video in a Facebook posting. I hope the link is permanent because the comments indicate there is a lot of controversy (and ignorance) concerning big windmills. One interesting tidbit is that windmills kill about 250 to 300 thousand birds each year. Glass kills 400 to 1000 million birds. Cats kill 3 billion birds. To summarize: 300,000 vs. 1,000,000,000 vs. 3,000,000,000. (I know there is a big controversy in Chicago about people who feed and have outside shelters for the feral cats in the neighborhood. The good news is that the cats kill mice, rats, etc. The bad news is that they kill song birds.)
|Brian Horsman posted|
Gearbox changeout today on a GE 1.5.
Jake Wiseman 1/2 done 3-1/2 to go
[Wow. Big windmills have not been around that long. I'm surprised the gearbox is shot already. That is expensive maintenance to setup the crane and take all of the blades and hub off. It sounds like just four of the windmills in this farm need a replacement.]
If a bad component is not caught soon enough, it can get so hot that it causes a fire. There is evidently a lot of oil in these units because one of the environmental complaints I have read is that these windmills pollute the ground with leaked oil.
|Robert Pickel posted, April 13|
|Robert Pickel posted|
James Dunlap I unloaded all of the nacells for those Chinese turbines with a 2250 series 3 and it was all she wanted.
Robert Pickel This one was supposed to be a lil lighter but it still weighed 365,750 lbs,
Bobby Eddy The fire didn't damage the spike at all?
Robert Pickel It passes metal urgentsee test.
Robert Pickel I'm talking to the rep now he said it's been up 5 years.
Ryan Chapman Where is this?
We've got a burnt out one in McBain MI at Stoney Corners Windfarm too.
|Bryon Moorhead posted|
This week's project, blade change out, 100 meter tower, American 8460-360' boom, Manitowoc 2250.
Virginia mn. Broken rotor repair.
Ben Reich The next one has a cracked blade. They have blade guys in suspension baskets working on them now.
|Ronald Ritter posted|
My son John atop a windtower west of Shelby, Mt in 08.
|William Lee posted|
Wind turbine salvage with a 16000, Palouse WA
Ted Fortier Salvage? That sounds like a fun day.
|Cody Printz posted|
MLC 300. JMS Crane & Rigging. Horse Butte Wind Farm, Idaho.
Cody Printz We are currently using blade rigging, for blade exchanges, gear box rigging for gear box exchange, and generator rigging to move gen out of way. All done with the MLC 300.
[There are several comments about no mats in a farm field. Also comments about a "wind attachment." I haven't figured out what a wind attachment is yet.]
|Cody Printz posted|
MLC300. JMS Crane & Rigging. Idaho
Cody Printz This is Horse Butte wind farm. Idaho Falls. Existing wind farm.
[At first I was impressed because it was not only on mats, it looks like the mats are steel instead of wood. But then I noticed the dirt ramps on this side of the maps. So they still ran the risk of travelling between towers on just dirt "roads." But since this is maintenance, as a comment pointed out, the "roads" have already been tested. This went online in 2012, so after just 6 years they are having to do maintenance that is extensive enough to require a crane. The hub height is 87m (285').]
Ben Stalvey The 16000 sure are. Seems the MLC 300 are taking over them though.
This would be why you want to keep all of the bearings well lubricated. Or was it built with something out of alignment?
|Screenshot @ -0:38|
I keep learning more about how high the maintenance costs are for wind farms. They have not been around that long and already some of the blades are being decommissioned. Fortunately, a company is reusing a manufacturing plant to repurpose fiberglass. There is more than 15,000 pounds of fiberglass in each blade.
A three minute video showing that there is a variety of failure modes, all look expensive. (source)
These comments are from a different Facebook video posting. That link is now broke. But it may have been this video.
Christopher Thomas Over speed braking failed. Wind turbines must be locked in high winds. The blades have a speed limit.
Eric Kurowski That video is 14 years old.
The new power plants have multiple layers of safety to prevent such catastrophic structure failure. Come to Wisconsin where they are made and we can show you.
New technology in the Rotor Blades eliminated the over run senerio.
MidAmerican will spend $1 billion 'repowering' oldest wind turbines [Caution: this web page hogs a lot of browser memory.] This article has 16 photos you can flip through. 706 older turbines are going to have everything except the tower replaced. This contractor lifts one blade at a time and spends about a half hour to "stab" them into the new hub on the new nacelle. MidAmerican also plants to add 1,000 more turbines for $3.9b to the 2,020 it already has. Both projects should be done by 2020 and supply 95% of the customer's power. The reason for the 2020 deadline is that tax credits might phase out by then."With its $3.6 billion expansion, MidAmerican expects to pay $12.5 million each year in property tax payments and $18 million in landowner payments."
|Kelsey Kremer/The Register|
This is one of the 16 photos. It had the caption:
Workers from Mortenson Company attach a wind turbine blade to its rotor before it's lifted by a crane and placed on the wind turbine tower at MidAmerican Energy Company's Century wind farm on Wednesday, Nov. 8, 2017, in rural Blairsburg. The Century farm is one of three MidAmerican wind farms undergoing renovation this year.This photo made me understand that the article is ambiguous. Is the "stabbing" happening on the ground or in the air. It appears the stabbing is done on the ground and the whole rotor assembly is lifted and attached to the nacelle.
The source for the article's link was an Electric Nation: Powered By Wind posting. There are a lot of comments about wind power not being economical compared to coal-fired power plants. Also, when wind is providing 95% of the grid, is the wind really strong enough during the day to provide all the needed electricity? Maybe if you have enough farms spread across the state it is blowing somewhere.
Jimmy Widman posted three photos with the comment: "Vic's Crane and Heavy Haul GMK6400 and GMK6250L doing a blade swap in Lakefield MN."
|Bobby Casados commented on a post|
[This is a screenshot from a video, but I could not figure out how to get a link to the video. The important thing is that they are bringing that hub and blade assembly down. Note that they also have a pretty big hydro-crane at the project.]
[That is not going to buff out. Once again, Facebook no longer saves a link to the post. But the comments indicated that the bolts were probably over-torqued. And there were plenty of comments about cheap Chinese steel.]