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The Rocky Road To Wind Power
Hugh Pickens writes "The NY Times has an interesting story on the logistical problems involved in transporting disassembled towers that will reach more than 250 feet in height from ports or factories to the remote, windy destinations where the turbines are erected. In Idaho trucks laden with tall turbine parts have slammed into interstate overpasses requiring hundreds of thousands of dollars in repairs. In Texas the constant truck traffic is tearing up small roads in the western part of the state where the turbines are being rapidly erected. And in Maine a truck carrying a big piece of turbine got stuck for hours while trying to round a corner near Searsport."
"'It left a nice gouge in Route 1,' said Ben Tracy, who works nearby at a marine equipment store and saw the incident. On a per-turbine basis, the cost of transportation and logistics generally varies from around $100,000 to $150,000, said John Dunlop, an engineer with the American Wind Energy Association, and experts say that transportation logistics are starting to limit how large — and as a result how powerful — wind turbines can get. There is talk of breaking a blade up into multiple pieces, but 'that's a very significant structural concern,' says Peter Stricker, vice president at Clipper Windpower who added that tower bases were getting too large to squeeze through underpasses. But a partial solution may be at hand. While vast majority of turbine parts now travel by truck, in Texas and elsewhere, some wind companies are looking to move more turbine parts by train to save money. But even the train routes must avoid low overpasses when big pieces of wind turbines are aboard. 'It's not your typical rail-car shipments,' said Tom Lange, a Union Pacific spokesman."
Someone want to calculate the minimum safe stopping distance of a wide-load truck laden with a 50-meter section of tower traveling at, let's say 45MPH without jackknifing or breaking the load restraints?
IMO, the problem isn't the truck drivers, it's either failure to properly plan the route by the companies, or else improper height measurements. Those signs on the overpasses are for surveying the route, and not really effective as a last-minute warning.
https://www.eff.org/https-everywhere
I often wonder why they build them with a single-stem trunk? Surely a triple- or quadruple-stem trunk could give added stability with a lower materials cost, and greater ease of transportation, if greater assembly time.
For that matter, why not have two (or, of course, more) propellar sets one above the other? Harness not too much less than double the amount of power without needing larger individual propellar blades.
I'm sure there are fundamental reasons why these wouldn't work, but I'm not an engineer.
Tubes are extremely strong, so you don't really need multiples. Plus, all of these turbines have the capability to rotate, as far as I know, and rotating one turbine around one tube is a lot easier than rotating a gang of them around without their blades hitting something.
They're just keeping it simple. Some of the generator bodies are the size of a small bus, they just don't look like it from far away.
-Taylor
Worldwide Military budgets: $2100 billion. Worldwide Space Exploration budgets: $38 billion. Really, world? Really?
When I worked on road systems we installed simple IR light interruption height sensors before bridges. The sensor triggers a warning sign so the driver knows they are over height. Of course some drivers have this idea that the warnings are always set a metre too low. Most of our low bridges have sacrificial steel beams fitted before the bridge. That way the expensive concrete doesn't get hit.
At the end of the day the truck driver should know how high their load is.
http://michaelsmith.id.au
I'll pick three: three of the last four airships built by Luftschiffbau Zeppelin
#1 LZ-127, the Graf Zeppelin : 11 years of safe, reliable operation, including a flight around the world and a million miles of passenger service. Scrapped at the beginning of World War II.
#2 LZ-126/ZR-3, the USS Los Angeles : 10 years of safe, reliable operation. Scrapped at the beginning of World War II.
#3 LZ-130, the Graf Zeppelin II : two years of safe, reliable operation. Scrapped at the beginning of World War II.
The big threat to properly-designed rigid airships seems to be World War II. Now that it's over, new airships shouldn't have any trouble.
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
The larger the turbine and the higher it gets, the more efficient they are, both in construction and operating costs and in electricity delivered. see : http://en.wikipedia.org/wiki/Wind_turbine_design#Turbine_size
They are getting close now to maximum size because of materials science limitations (cost/benefit), and also because of the transportation limits mentioned in the article. Much larger ones could be built directly adjacent to a seaport dock then barged to a direct sea or coastal installation point, but once you have to transport them on land, it gets iffy. Notice the shuttle has to be flown back piggyback when it has to land at edwards-there's simply no reasonable way to move the thing on land, just too big.
Now there's some HUGEMONGOUS mining equipment out there, but it doesn't travel on the roads, and even to transport the things (excavators, dump trucks, crawlers, etc) they have to be partially disassembled and then reassembled on site and they use rail transport as much as they can to get to the site.
Just for fun if you like big land stuff
http://en.wikipedia.org/wiki/Bagger_288
http://en.wikipedia.org/wiki/Liebherr_T_282B
http://en.wikipedia.org/wiki/Caterpillar_797B
http://en.wikipedia.org/wiki/Komatsu_D575 (we have two impressive big crawlers here on the farm, serious big oak pushing around brutes, smaller than this bad boy though, one is 114 tons and the other one I don't know, looks to be a scosh bigger)
and I always liked this one, I wanted one as soon as I heard about it when I was a kid ;)
http://commons.wikimedia.org/wiki/Category:Alaskan_land_train
What's neat about this stuff... real terraforming
It's not a question of cherry-picking. Lightning does not ignite dirigibles because they're filled with hydrogen, which does not ignite unless mixed with oxygen. Most dirigibles of the time passed through thunderstorms and were hit by lightning repeatedly, without harm. The problem is that these ships vent hydrogen when landing. If struck then, the ships could ignite. Fortunately, modern blimps don't use hydrogen at all, so there's no chance of them being ignited by lightning.