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Electromagnetic Ship Docking System Debuts
Makarand writes "A system that uses electromagnets for docking ships is getting ready to be tested at a port in the
Netherlands according to this
article in the New Scientist. Magnetic docking systems were never used in the past as magnetic fields
posed dangers to sensitive cargo like TVs and monitors. Researchers at the
Delft University of Technology have developed electromagnets whose magnetic fields do not
penetrate far into the ship for this special application.
The magnets can be periodically switched off and on rapidly to allow ships
to rise and fall with the tide."
The real problem is not in having a ship moored with ropes, but in getting ropes from the ship.
Once moored, nothing is easier than throwing a line and having your backup.
Powerfailures in the Netherlands used to be extremely rare. I'm 38. I can remember four powerfailures. There might be one I missed, but no more. They also tend to last short. 30 minutes to 4 hours. They're privatizing the electricity-sector, which used to be state-run, so the rate of powerfailure is going up, but is still no way like America. Let alone California.
Mostly, the chain and combo lock doesn't address the issues which electromagnetic mooring systems do. There are a lot of factors involved with a project like this, including sway, roll, and yaw of the boat, which chains and locks don't handle. The chain and lock system acts like a yo-yo or a swing, in so far as two objects are attached together by a string. The electromagnetic mooring system acts like, well, a refridgerator magnet does to a refridgerator.
I'd worry about permanently magnetizing the hull.
Sure, there won't be enough residual that it sticks to other passing ships, or anything, but what about interference with magnetic compasses.
I had a steel-tube frame airplane, and it got so magnetized from arc welding that the mag compass was totally useless. No amount of swinging could correct the compass deviation. Nor did it help to replace the mag compass with a new one. I ended up degaussing the whole fuselage with a degauss coil designed for TV sets, and never had the problem again.
But I can't see doing that on the scale of a container ship!
5,000,000 Euros = 5,335,000 USD
Storm force 12 = 80 knots = 92 MPH
I dunno. I work with 1.5T magnets, and I think they're talking about much bigger ports and mooring systems than that.
At the very least, according to the cost of medical grade 1.5 Tesla magnets, your initial costs for the electromagnet system could be off by as much as a factor of 1000. (1 Tesla magnets can cost a cool $1M each, with computer systems, real estate infrastructure upgrades, and all. And they're talking about a 52 magnet system.). My guess:
Electromagnets: [Inital Costs: $50,000,000; Ongoing Costs: $100,000 per year]
Lots of Ropes: [Initial Costs: $100,000; Ongoing Labor Costs: $5,000,000 per year (for 200 dock workers)
Five years down the road, the investment pays off real big.
But I don't know that for a fact.
Not that I think people should be kicked out of jobs by robots.
Why not? Why put the interests of a few (the small minority of people with 'traditional' industry jobs) before the common good of the many (who will enjoy higher standards of living with increased automization).
WOW! That's strong. I used to work with a 1.5-T superconductor magnet, an MRI scanner, and it had a heck of a pull. Enough so that people have been injured or killed when a piece of metal got loose
This is a fair point, but one should keep in mind that what is dangerous is intrinsic to the powers necessary to pull a large ship. A more traditional solution probably involves powerful winches, which of course can pose risks if a cable snaps or somebody gets a hand in the wrong place.
Tor
Navies spend a lot of time and money making sure that their ships have small magnetic signatures -- magnetic triggers are common in undersea mines. Somehow slapping a few big magnets on the side of a ship everytime it docks doesn't seem like a good idea.
Calling Rotterdam just "a port in the Netherlands" is an understatement: Rotterdam is the largest port in the world and has been for some years...