New Age Trawler/Motorsailer; Kite assisted PowerYacht

[masalai]

From my observations of the joy-riders in the "surf" at the mouth of the Maroochy River I must solidly agree with Munter, Too many control issues to be resolved as yet for significant upwind work.

Brian I hope your inventive attitude and developments continue & you can resolve the upwind issues for say a 40ft cat! I would like that as an alternative motive force, else the "hitch-hiker" form will have to suffice for me. Thanks.

[Guillermo]

How many sqm of kite would you say you'd need for your foreseen speed, asuming 1kW/sqm as mean power?

[masalai]

Guillermo, I hope that Brian Eiland can answer that as I have only got to the "its interesting stage & what are the control/performance issues". . The "joy riders" seem to have up to 15 sq metres....?

[brian eiland]

Originally Posted by Pericles

Brian, I truly hope this concept is taken up, because you have pioneered many really good ideas.

Best regards, Pericles

The credit should go to Guillermo who brought it to my attention per my notation in the originally posting: "Brian: You should try this also for your big game fishing catamaran" at posting #285

I just took up the banner, and hope to run with it.

Originally Posted by Guillermo

How many sqm of kite would you say you'd need for your foreseen speed, asuming 1kW/sqm as mean power?

Originally Posted by masalai

I hope that Brian Eiland can answer that as I have only got to the "its interesting stage & what are the control/performance issues". . The "joy riders" seem to have up to 15 sq metres....?

Sorry guys, I do not know this sqm figure yet myself. I would assume there will be a considerable range of possibilties depending upon the clients desire to split the wind verses diesel capabilities, and his desire to fly the kite in more complicated patterns, or in more demanding conditions...both more costly.

The basic catamaran platform is extremely stable to carry a relatively large kite without concern for lift-off or capsize, and the configuration of the basic ship might well be the same for a smaller or larger kite. So the client might wish to play it conservative to start with, and only need to increase the kite size in order to upgrade, without a redesign or rebuild of the vessel.

I'm presently looking at an existing production 50' catamaran that might well lend itself to the initial vessel, or even an existing used vessel. Just need that bold adventuresome client/sailor willing to experiment with his new power cat

[brian eiland]

A cargo ship has set off from Bremen to Venezuela to gain first-hand experience being towed partly by wind power. The newly built cargo vessel was towed by wind propulsion for the first time in the North Sea this month. The 160m2 SkySail supported the main engine of the 132m long Carrier MS “Beluga SkySails” of the Bremen-based Beluga Shipping with approx. five tons of tractive force at a low wind speed.

The invention is that of a Hamburg-based company SkySails GmbH & Co.

“The maiden voyage marks the beginning of the practical testing during regular shipping operations of the SkySails-System. During the next few months we will finally be able to prove that our technology works in practice und significantly reduces fuel consumption and emissions,” says Stephan Wrage, Managing Director, SkySails.

Parallel and in addition to the practical tests on the MS “Beluga SkySails”, the SkySails technology is advanced and optimized for series production readiness on further ships.

Stephan Brabeck, Technical Manager at SkySails: “Certainly, the daily routine at sea will still bear many challenges for SkySails. It is thus now particularly important to raise the manageability and robustness of the system to the level demanded by our customers. We will have to face up to many challenges and in the process learn many very valuable lessons.”

The shipping company and the manufacturer calculate that by using the towing kite system, a ship’s average annual fuel costs can be reduced by between 10% and 35%, depending on the prevailing wind conditions. Under optimal wind conditions, SkySails estimates that fuel consumption can sometimes be cut by up to 50%. The first results are to be expected in the next few months.

“Interest in the SkySails technology among shipping companies from all over the world was already high before, but especially during the last year and in light of the rising oil prices it has increased considerably,” states founder of the company Stephan Wrage.

They hope the state-of-the-art kite will help reduce carbon dioxide emissions, as it tugs the ship.Fuel burnt by ships accounts for 4% of global CO2 emissions - twice as much as the aviation industry produces.

[masalai]

Thank you sir, I will keep my eye on developments in this thread.

[mark424x]

I wonder if anyone could comment on the ability to get any upwind VMG out of such a kite rig on a power boat hull. I can't image you'd get much dynamic lift from a cruiser like a hatteras/defever/navigator, but I wonder if you were in a displacement power catamaran Tennant/PDQ/MaineCat or maybe even a traditional trawler, DDuck, if you'd get enough lift to get to 60 deg to windward.

In addition to added power, the additional roll stability would be an added value.

Here on the US West coast, you could pop your kite in Alaska and ride it south to Panama. Even the sailboats mostly power going north.

[masalai]

mark424x,
Hi All I can suggest is you try it and be a net hero by posting info.... Do they have those kite boarders getting air when there is a nice breeze and a bit of chop from which to launch? they are about 15m2 for the big light air wings which you could trial on your next cruise - If not as good as you would like can be sold to a wind-surfer in California etc

All I can do is wish you well and every success...

[brian eiland]

Originally Posted by mark424x

I wonder if anyone could comment on the ability to get any upwind VMG out of such a kite rig on a power boat hull. I can't image you'd get much dynamic lift from a cruiser like a hatteras/defever/navigator, but I wonder if you were in a displacement power catamaran Tennant/PDQ/MaineCat or maybe even a traditional trawler, DDuck, if you'd get enough lift to get to 60 deg to windward.

Here on the US West coast, you could pop your kite in Alaska and ride it south to Panama. Even the sailboats mostly power going north.

Did you have a look here:
http://www.skysails.info/fileadmin/u...nformation.pdf
...specifically page 3

[brian eiland]

Originally Posted by Munter

One thing that would make that upwind performance difficult to repeat with a motor yacht is the loss of the reflex like control that the rider has when the bar is directly in his hands and the board directly on his feet. A kiter is constantly playing a dynamic balancing game controling kite line pressure, kite line angle and the angle of the board in the water (sideslip resistance). If this balance isn't maintained you can end up getting dragged downwind or falling back into the water. Replicating the instantaneous control of all those variables on a larger structure would be a complex task! As I understand it the kites were predonminantly intended to help with downwind sailing which I think would be an easier control task.

I'd love to see kite-ships going upwind but I think they have a fair bit of development to go before it can be done.

Maybe time to re-review this YouTube reference that Guillermo brought to us back in posting #9

http://www.youtube.com/watch?v=qnACybMhPs4&NR=1

http://www.kiteforsail.com/

[mark424x]

Originally Posted by brian eiland

Did you have a look here:
http://www.skysails.info/fileadmin/u...nformation.pdf
...specifically page 3

Thanks, yes. As I understand it, the only way to get close to a beam reach (or higher) is to have hydrodynamic lift from a keel or the underbody shape of the hull. My assumption was that you'd have to modify a power monohull to get any appreciable lift, but was hoping that a displacement power cat might have enough lift from the slender hulls. But that is a complete intuitive guess.

[masalai]

Thanks Brian, advances are being made - so good to see

[Tad]

So the Beluga SkySails has now crossed the Atlantic but they are not releasing any information on performance until its "properly evaluated"??? This encourages my skepticism. They claim a 3-5 year payback period for the system, which costs approximately half a million euros. They do not state what is included in that cost. Does it include financing cost? Additional insurance? Increased manning certification? What is the maintenance and down time really going to amount to? If the ship costs more to purchase and operate, shipping costs go up, is that included in their costing?

What does the Beluga SkySails carry anyway? Why not totally eliminate the need for that transportation? Would that not be even more environmentally friendly?

[brian eiland]

Tad,
I don't think I would be in a GREAT rush to release this raw data yet if it were me...particularly with the clientel they are appealing too...the big commercial shipping guys.

One wrong move and you could turn them off to continued and future developments. I've seen a few advanced ideas fail as a result of premature hype.

Originally Posted by Tad

Why not totally eliminate the need for that transportation

Are you suggesting that all small ships such as inter-island traders be scrapped in favor of big ships??

I found it interesting that the remains of the racing trimaran Groupama were being shipped back to France from New Zealand on a relatively small ship carring fresh produce to Holland I believe.

[Munter]

Tad - minimisaiton is a good idea but it should be done in parrallel with efficiency improving technologies. Some things will still need to be transported.
I wonder if oil at $110/b will be enough to change the status quo?