Everything old is new again

[mdlbear]

Blowing in the Wind - Global Business - MSNBC.com

A German company is introducing sails it says may help propel ships across the sea cheaper and faster than modern engines.

SkySails' system consists of an enormous towing kite and navigation software that can map the best route between two points for maximum wind efficiency. In development for more than four years, the system costs from roughly $380,000 to $3.2 million, depending on the size of the ship it's pulling. SkySails claims it will save one third of fuel costs. It recently signed its first contract with Beluga Shipping of Bremen, Germany, for one kite, but says it expects to sell 300 more within five years. Beluga says that the giant kite will help the company meet environmental regulations as well as cut fuel costs.

The sail systems are meant as a retrofit technology that can work with any cargo ship as well as yachts of more than 79 feet. Ships can use their engines to begin and end voyages and use sail power in lieu of engines for the middle portion. Use both, and you go even faster.

Yes, but how do you sail close-hauled?

Comments

[technoshaman.livejournal.com]

Yes, but how do you sail close-hauled?

Hey, that's Rev 2.0 and requires the keel update....

OMG, are we going back to sail power after all these years? I can see it now, cargo ships with retractable centerboard structures... and big carbon fiber masts and sails.. the only problem I forsee is container ships that depend on being level.... oooh! Catamaran!

Now you've got me all excited....

('course, it's also that I'm going to see Jack today... ARRRRR!!! Hoist the mains'l, trim the t'gallants, FLANK SPEED!!!!)

[mdlbear]

I'd be inclined to use leeboards rather than a centerboard -- better adapted for a twin hull anyway.

Possibly airfoils rather than sails, since they give more lift when close-hauled. The kite actually has an advantage on a broad reach; there's a reason why "kite" is a common nickname for the spinnaker.

In any case you'd use kevlar rather than carbon fiber for the sails; carbon fiber is brittle. Great for masts and hulls, though. Not to mention guitars.

[technoshaman.livejournal.com]

Actually, sails have an advantage that would be difficult to do in an airfoil: Furling. This is of great advantage both in heavy weather and, if you also fitted telescoping masts, in harbors where there are fixed bridges of any sort. The height of sail it would take to effectively power a truly large ship would be prohibitive in any harbor with fixed bridges...

On leeboards, yes, agreed... and I knew about the kite. I've seen one flown, at close quarters (i.e. I was standing next to the crewmember who had both spinnaker sheets in his hand, flying the kite on a dead run... neat.)

You didn't tell me you were a sailor, did you?

[mdlbear]

Used to crew for my uncle back in '60mumble when he had a 26' Quincy Adams sloop on Long Island Sound. I've done next to no sailing since then. Always wanted to, but other forms of fun keep getting in the way.

[technoshaman.livejournal.com]

As for the guitars, *wow*. And they're made apparently right around the corner from me.

[mdlbear]

They're even more gorgeous close-up.

[elimloth.livejournal.com]

It is good to see people trying to increase the efficiency of these large ships. When you mentioned the kite approach, it reminded of another project: the turbosail. I do not think it got very far, but here's the link.

http://www.cousteau.org/en/downloadfiles/alcyone_and_turbosail.pdf

[mdlbear]

I remember those! And every once in a while I see a reference or a picture. Not entirely clear what the problem is, but I expect there is one.