Cargo Ship to fly a Kite

[RaptorDance]

From Engadget.com:

A 132-meter long cargo vessel will be making its maiden voyage next month, but rather than chugging copious quantities of diesel while traversing the Atlantic, it'll be sipping down fuel and receiving a good bit of help from the computer guided kite attached to its bow.

The $725,000 device will be tethered to a 15-meter high mast and will fly some 300 meters above the ship in order to catch enough wind to actually aid in its movement. It's suggested that the SkySails kite propulsion system will slash fuel consumption by "up to 20-percent," saving the operator some $1,600 per day.

For the full story see:
German ship fights climate change with high-tech kite | Reuters

Pictures and an interesting video are linked off the above article

[Kanani]

I'll believe it after it's been in operation for 5 years. I think somebody pulled off a good "Sails" job and won't be around when the results come in. I sure don't see $725K worth of equipment there. That must have included a 50% kick-back to somebody.

HMMMM!! I seem a bit cynical

[MarkJ]

Originally Posted by Kanani

I'll believe it after it's been in operation for 5 years. ...HMMMM!! I seem a bit cynical

pesimist!!!!! Pesimist! PESIMIST!!!!!!!!

I reckon give it 4 years 364 days....

Note it says UP TO 20%. So thats above 30 knots apparent up the butt? On a 10,000 tonne ship.... unladen?

[CSY Man]

Great Idea..!

Hope it works out as planned and that we see more and more of that kind of technology.
Perhaps they have to design ships especially for the para-sails: Longer waterline, narrow beam, lighter construction, carrying light cargo..?

Back in the old days, the biggest and most powerful sailing ship ever made, generated about 5,000 HP from her sails on a windy day.

With todays technology that could easily be doubled one would think.

Good luck to the pioneers trying to do the right thing.

[hellosailor]

Not bad, a 450-odd day period until it is paid back, figure two full years of use to make it really paid back, and then it's pure profit. Assuming it doens't need to be replaced, like most sails and rigging, by then.

Hmmm....Can anyone say "Spinnaker tangle" with a vengeance?[g]

[delmarrey]

I hope it succeeds!!! I've been watching the kite industry for a while and haven't seen a lot of negative feed back.



KiteShip - Innovation in Tethered Flight

Kite LandBoards

[David M]

I don't see how it can make any money competing against modern day container ships, some of which are over 1000 feet long now These ships are on tight schedules and fully laden cruise typically at 23 to 27 knots. Does anyone see a problem yet? Apparent wind....which way would the kite be pointing in most all wind situations? Backwards, effectively becoming a parachute causing drag on the vessel. Even in a good crosswind, the parachute would be aft of abeam of the ship...effectively applying drag to the ship. It would be a very rare situation where they could launch a kite and it would fly forward of the beam.

A ship on a route is by definition going with wind with an aft component half the time....and this is when the ship is dead in the water. Add some speed through the water and that vector shifts aft. Making it less than half the time that a ship has the apparent wind forward of the beam. Make it a fast ship and the time the apparent wind is forward of the beam will be a rare occurrence.

Lets say hypothetically it is a very slow ship...like 12 knots. Even then it will be a rare occurrence when the ship is going enough downwind to justify launching the kite. Crews are not cheap. Is the additional crew necessary in order to launch and retrieve a kite really make up for the tiny fractional savings in fuel for a kite what is flown on rare occasion? It's all business at sea trying to save costs so a company can remain competitive. Shipping companies are not going to be inclined to do feel good environmental things unless they are forced to do so. We wont be able to force ships of other countries to do this. If it was forced on US Merchant ships it would make the US merchant marine even less competitive against Taiwan Korea, Japan and China.

One more factor is size. How large of a kite would be necessary to have any effect on a ship that is almost the size of an aircraft carrier? (1123 feet) Ships compete by economies of scale. The bigger they are the more efficient they are and the faster they become.

Perhaps it might work on some very small, slow speed ships that follow the trade winds. Thats the only scenario I can imagine. This though is a very small percentage of merchant ships.

[Boracay]

Le'me see now...

If we assume $10k/day fixed coats for the cargo boat and use of the kite doubles a 10 day voyage then the owner is up for $100k and has unhappy shippers.

I'll bet $100k still buys a lot of fuel.

[Tropic Cat]

I can't believe they actually sold this concept. With this ship design we just went back 150 years in history and reinvented "Trade Wind" clippers. I can just imagine the new 'old' book that will be written titled: "Two Years before the mast.... er...Kite"

[delmarrey]

I once heard it said buy one of our prestigious members;

Man was not put on the moon and successully retreived without technology which many sailboat people still condemn as being something that "if it hasn't failed it will" which is a fallacy flying in the face of successful facts. By repeating such defeatist anti-technology drivel
such people are merely ensconcing themselves in caves amidst a world of
wonderful opportunity. Don't deny others with such defeatism who might
otherwise benefit from the bigger picture.

How can one condemn a method that hasn't been tried?

[hellosailor]

"How can one condemn a method that hasn't been tried?"
Easily. If the method doesn't make sense from the start, or sounds impractical from the start, it may be worthy of condemnation from the start.

In this case...someone apparently thinks it is worth an investment, ergh, gamble. And absent the details, all we can say is that SOMEONE got convinced to put up the money. Maybe it's a write-off for a drug cartel.[G]

[CSY Man]

Easily. If the method doesn't make sense from the start, or sounds impractical from the start, it may be worthy of condemnation from the start.

That is what some folks said 110 years ago when some nut-cases were trying to invent a Flying Machine....

[David M]

It makes perfect sense to try out new technologies because you just don't know what the outcomes will be when you are dealing with unknowns. Here though, there are no unknowns. We know all about sails..right? We know all about the two vectors that create the apparent wind resultant vector...right? We know about the forward and lateral force vectors that a kite would create. We have a pretty good idea of the lateral resistance of a ship. We know all about resistance through the water. We know how much a force a propeller applies to a hull versus that of a kite...right? All of this is basic sailing technology and known naval architecture formulas..

What technologies do we have here that are unknown?

I mean it is a pretty darn simple idea. I don't see any untried things here that cannot be quantified on paper or with a computer. I wonder if anyone ran the numbers?

I don't mind seeing it tried. It should be interesting to see someone try to save money and fuel by flying a kite off the bow, on those relatively rare occasions when the apparent wind is far enough aft of the beam and not to strong or light, to make any difference. But, I don't think I would put any money into it.

[SkiprJohn]

I'd prefer to see folks invest in real sailing ships. I'm a real pessimist on this experiment but will take a wait and see attitude.

JohnL

[David M]

I would be most concerned about a ships relatively small metacentric height (especially container ships with all their existing windage) and a kite pulling high and laterally on the hull causing a relatively high moment arm that works against the ships righting moment.