Technology Amazing New Propulsion Technology Will REVOLUTIONIZE Maritime Travel

[Husky_Khan]

Seriously, how come no one ever thought of this before? It seems so obvious in hindsight.





Have we seen this before?

Giant kites that drag cargo ships across oceans go on trial

The kites are being developed by Airseas and its main aim is to cut fuel emissions.

economictimes.indiatimes.com

 

[Bear Ribs]

Using the power of wind to propel ships across the water is certainly a novel and original new technology.

 

[Typhonis]

But are these kites the most efficient use for the wind? Could a different system be more efficient? Mabe attaching the kite directly to the hull by way of something?

 

[bintananth]

But are these kites the most efficient use for the wind? Could a different system be more efficient? Mabe attaching the kite directly to the hull by way of something?

Ship owners are cheapskates and sailors who know how to properly handle a fully-rigged ship are neither common nor cheap.

 

[VicSage]

Babylon Bee already has a thread.

 

[Robovski]

Ship owners are cheapskates and sailors who know how to properly handle a fully-rigged ship are neither common nor cheap.

Well, not anymore anyhow.

 

[ParadiseLost]

Probably going to fail.

The reality is that when it comes to decarbonization, trying to go back to old tech (1950s) is generally far more effective than new tech - but saying you're going to reuse old tech won't get you that venture capital.

 

[Large_Farva]

The concept has been around for a while. IDK how long exactly, but looking it up on Wikipedia there was a prototype launched in 2007. So it had to be a while longer than that for someone to think it was worth investing several hundred million into.

But are these kites the most efficient use for the wind? Could a different system be more efficient? Mabe attaching the kite directly to the hull by way of something?

Traditional sails require a ship to be designed around them, which requires considerable design compromise(check out Sailing Yacht A though, for an example of a motorized sail-assisted vessel with comparable interior volume to a motor-only ship) to construction and layout. Plus upfront costs, plus plus the massively increased air draft limits the ports that a sailing vessel can use.
The kite sail, on the other hand, can be retrofitted onto existing vessels.

From Wikipedia:

The return on investment for installing a kite sail was estimated to be about two-three years.[5] On her maiden voyage, MS Beluga Skysails saved an estimated 10–15% fuel, $1,000 to $1,500 per day, while the kite was in use.

Probably going to fail.

The reality is that when it comes to decarbonization, trying to go back to old tech (1950s) is generally far more effective than new tech - but saying you're going to reuse old tech won't get you that venture capital.

1950's tech is neither clean nor efficient.

 

[ParadiseLost]

1950's tech is neither clean nor efficient.

I worded that poorly. I didn't mean returning to 1950s tech specifically, but returning to tech that existed before the 1950s.

A lot of these newfangled "green energy concepts" are really stupid, and less efficient at reducing carbon (and other goals) than technology that's existed since the 1800s.

 

[Captain X]

Seems to me there was an attempt at a "modern" sailing ship some decades back which used small motors to turn vertical cylinders which were the masts/sails, and this apparently actually worked fairly well using only a couple of them. It also seems way less stupid than putting a giant kite on the front of a ship.

 

[Large_Farva]

I worded that poorly. I didn't mean returning to 1950s tech specifically, but returning to tech that existed before the 1950s.

A lot of these newfangled "green energy concepts" are really stupid, and less efficient at reducing carbon (and other goals) than technology that's existed since the 1800s.

Pretty sure using air currents for motive power was extant in the 1800s (and even before!)

Seems to me there was an attempt at a "modern" sailing ship some decades back which used small motors to turn vertical cylinders which were the masts/sails, and this apparently actually worked fairly well using only a couple of them. It also seems way less stupid than putting a giant kite on the front of a ship.

Flettner rotors. They've been experimented with for some time, with multiple vessels constructed using them to improve fuel efficiency, including on a couple of commercial vessels in this century. They do show promise, though they seem like they'd be more expensive to put into a ship, vs a kitesail. Plus, the air draft problem.

 

[ShadowArxxy]

Seems to me there was an attempt at a "modern" sailing ship some decades back which used small motors to turn vertical cylinders which were the masts/sails, and this apparently actually worked fairly well using only a couple of them. It also seems way less stupid than putting a giant kite on the front of a ship.

What's the saying? If it looks stupid but it works, it's not stupid.

 

[Simonbob]

What's the saying? If it looks stupid but it works, it's not stupid.

Or, If it's stupid and it works, it was still stupid, and you were lucky.


Mostly aimed at teens doing something dumb they just lived through, but, still.

 

[Captain X]

It just strikes me as terribly inefficient compared to other, older technology at actually harnessing wind power, and makes me wonder exactly what metric they are using to determine success here. If all one is looking at is fuel consumption, well, that makes me wonder about time, because wind power under the best of circumstances isn't going to get you around as fast as good engines will accomplish, and time is money to a shipping company. And given how massive these cargo ships are, I very much doubt these kites are going to drag them around very fast, even under the most favorable wind conditions. So I'm going to be forced to stick to my assessment of this being a stupid, inefficient, feel-good idea that only really succeeds at lining the pockets of whoever has taken advantage of the environmental guilt complex of the people running these shipping companies.

 

[ShadowArxxy]

"Time is money" is an overly simplistic truism; if that's all there was to shipping, everything would be going by air freight.

The money maker for ocean freight is hauling very, very large volumes of non-time-sensitive cargo for vastly lower costs than air freight. The big container freighters are largely standardized at 25 knots, but in recent years most companies have adopted "run slow" operations at 20 knots or even "super slow" at 12 knots in order to save fuel and reduce costs, along with tricks like these kite systems or hull bubblers.

 

[Captain X]

Those kites can drag a cargo ship at 12 knots? How long are they willing to wait to offload their cargo and get another load? What is the crew's time worth?

 

[Bear Ribs]

The problem I see with these kites is that they can't tack, or can only barely do so at best. To get a bit complex, a sail doesn't catch the wind and get blown by it like a kite. A sail is normally angled to the wind so that the wind is blowing across its surface and it generates lift like an airplane wing, except sideways instead of upwards. This generates massively more speed Boats rarely sail the same direction as the wind because this is highly inefficient and doesn't generate much speed, and also the wind never seems to be blowing the same direction you want to go. Tacking is the art of sailing literally upwind and zig-zagging to get maximum speed while going the opposite direction the wind is blowing.

There's a useful site here with some information on sailing into the wind and how fast it can be done by various sails, complete with equations. A decent pic of it from there:

What you might notice is that firstly the worst direction to travel is the same direction the wind is blowing (Except the opposite, you have to tack, that is, change course periodically to stay in a fast direction, to do that). Also because they're using lift generation, most of these boats actually travel faster than the wind is actually blowing, often hitting fifteen to twenty knots in a ten-knot wind.

Now, these kites, maybe you can get a slight bit of angle (the one in the picture has only one cable going back to the ship precluding that, which is stupid, there should be at least one per end if the kite isn't round to give some minimal control, even decent actual kites often have two strings for that purpose) but you're never going to manage to get it to act like an airplane wing without attaching it to a solid mast. Further, if your ship is already traveling faster than the wind is blowing, they'll just sag and do nothing. So basically super-slow and only able to go in the same direction the wind is blowing (it will likely never be blowing in the direction you want to go). Pretty sure it's just a scam.

 

[ShadowArxxy]

Those kites can drag a cargo ship at 12 knots? How long are they willing to wait to offload their cargo and get another load? What is the crew's time worth?

No no, the cargo ship is already going at ~12 knots. I think you're misunderstanding how these things are used -- they don't replace the ship's engines, they are an auxiliary system that gets deployed when the wind is favorable for a modest amount of "free" thrust that reduces ship fuel consumption.

They're not as good as proper sails, but proper sails aren't something you can install as a low-cost add-on that pretty much just bolts to the deck.

 

[Captain X]

I severely doubt these kites provide much additional thrust, particularly in the direction the ship wishes to travel in. If they claim they're somehow saving fuel by attaching a giant kite to the front of the ship, I am extremely skeptical.

 

[bintananth]

I severely doubt these kites provide much additional thrust, particularly in the direction the ship wishes to travel in. If they claim they're somehow saving fuel by attaching a giant kite to the front of the ship, I am extremely skeptical.

Think of it like the spinnakers used by racing yachts. The basic yacht rig of a jib and a Bermuda mainsail is easy to handle. It's also good for speed ... when the wind isn't blowing in the direction you wish to go.