Slashdot Mirror
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
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.
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.