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."

Comments

I don't get it

[ajuda]

I mean, wouldn't it be cheaper (and easier) to use a chain and combo lock? They could have all the locks use the same combination (like 1-2-3). It might take a bit longer to unload each container, but things would hardly ever break, and the technology would be very cheap.

So what does the dockworkers' union think?

[MacAndrew]

Seriously, in the U.S. we just recently had a paralytic dockworkers' strike. I don't think they'd be amused by this labor-saving innovation. Not that I think people should be kicked out of jobs by robots.

Each of their mooring magnets generates a 1-tesla magnetic field. (from NS article)

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. It took three of us to pull off the base of an IV pole (no one inside at the time). Some of the research magnets are 4-T or more. But these are all superconductors, and act like permanent magnets. The resisitive magnets here must produce tons of heat while gobbling electricity. Surely "auto-dock" wouldn't be too hard to design., with mechanical restraints?

One Problem

[Arc04]

Methods of Securing Ships:

Lots of Ropes:[Initial Cost: £10,000, Ongoing Cost: £0 (near enough)].
Electromagnets:[Initial Costs £50,000, Ongoing Cost: £1000s/month]

I think the problem is obvious here :)

Arc

Re:One Problem

[Anonymous Coward]

I fear that you seriously underestimated the likely cost of the magnetic system. The article states that 52 magnetic modules will be used plus a backup power supply.

Presuming a likely cost of something in the neighborhood of $5K per module (no reason to think they'll be any cheaper - this is after all, a 1-T magnet) plus another $5K-$10K per module to install (gotta tear up some bulkheads and find a way to attach the modules, tear up a parking lot and run electrical wire) plus another $50K for a backup diesel-powered 50KW generator (that's only one 1KW per module which is probably low), plus you gotta put the mooring out of service for a couple of weeks to do this with a probable lost business value of unknown size.

Intemize installation costs:
52 modules X $5K equals $260K plus installation of $260K to $520K plus backup power source $ 50K
Total: $570K to $830K
On-going costs:
50KW power 6cents/KWH $2160/month plus backup power maintenance $ 200/month plus magnet modules inspection/maint.$1000/month
Total: $3360/month
First year cost:
Installation: $570K to $830K
Maintenance: $ 40K $ 40K
Total: $610K to $870K

Now, hawsers are both more expensive and shorter-lived than you suggest, but the ROI this idea is still probably in the 10+ years - and by then you'll probably have to install new magnets and start over. A bad idea altogether.

Good for oil tankers

[jhines]

While the magnetic field would be bad for general cargo, something like oil wouldn't, so this could be used quite easily at an oil terminal.

Re:A solution looking for a problem

[Fastolfe]

No offense to you personally, but I'm seeing a lot of the same comments from a lot of different people.

First of all, this is an experiment.

Second of all, they seem to have convinced a lot of people in positions they probably got by knowing what they're doing that this has the potential to save a lot of time and money. Please concede at least the possibility that this might actually happen or at the very least, your uneducated concerns might have already been addressed by the educated.

Stop for a minute and repeat to yourself: I do not run a major ocean port. I do not run a major ocean port.

Re:Military vessels will never use this.

[Anonymous Coward]

With a commercial super carrier, time spent in port is essentially wasted (because the ship is not transporting anything). The less time is spent in port, the cheaper the ship becomes, and the cheaper the goods transported on the ship become.

The same is not quite true for navy vessels. There is no commercial (or military) reason for keeping them in port for as short a time as possible (during military operations they can be restocked at sea; when the world is at peace they may as well spend those 40 minutes extra in the harbor).

So I do not see the navy using this any time soon. However, I'm not sure if it makes sense for commercial shipping either - it sounds like an expensive way to dock a ship.

And of course most navy ships are like little boats when compared to commercial super carriers. A piece of string is enough to keep them from drifting away ;-)

Re:Appropriate technology or high-tech boondoggle?

[Mac Degger]

You know, those abbaci worked real well for centuries, too...why oh why did we ever think about replacing them?

Imagine the cost ...

[fygment]

... of an accident. I've been in the Navy for 20 years. Ship's hit hard sometimes, even with tugs, when the current, wind, etc. go against you. Right now it's a bit of wood that gets crunched. What's the cost on those magnets again? And as if water, salt, air and metal weren't bad enough, toss in some high current lines and huge magnetic fields. Seems very complicated, high maintenance, and for no obvious benefit.